A reasoned belief is one that is founded on empiricism and a logical argument. Hopefully, we’ll all agree that logic is sound. If you argue that logic doesn’t work, then there’s no point in discussing anything at all with you, because no chain of reasoning can—well, reasoning depends precisely on logic! Thus, I will presuppose that we agree on logic, though you may or may not agree that empiricism is necessary, and some would even claim that empiricism is not epistemologically sound.

First, let me define what I mean by empiricism (I am no philosopher; there may be more precise terms). I do not mean that what I see is necessarily reality (au contraire, I am well aware that our senses are flawed and our brains are prone to certain types of delusion). What I mean by empiricism is simply the following assumption: There exists a systematic relationship between external reality and the percepts of a healthy brain. I must define the brain as healthy: If it is not, it may not follow logic, and it may be plagued by hallucinations to the point where it cannot follow any sort of external reality. If so, alas, I posit that this brain is beyond help. It is not, I admit, impossible that this applies to any given brain, including my own; but absent evidence to this fact, it cannot serve me to believe it or to behave as though it were true, so I will assume that the percepts in my brain do systematically reflect an external reality. I do not, however, need to assume that the relationship is perfect—strictly speaking, all I need is statistical significance.

If I am allowed to assume both logic and empiricism (in the sense above), I can build up a consistent and coherent world view. It doesn’t matter (in principle) that the system is noisy—that some of my logic will be faulty and some of my perceptions incorrect. The assumptions suffice to formulate experiments, which allow me to verify my logic against observed reality, and cross-check my perceptions as much as I want. Repeated experiment lets me overcome the effects of noise in both argument and perception.

I will even take a controversial step and claim that logic needs empiricism for validation—the two cannot be extricated from each other. You cannot, after all, use logic to prove that logic is true—it’s circular (it only works if logic is true to begin with). If you are mathematically inclined, you may note that logic can be represented as a form of mathematics—I wonder if perhaps Gödel’s Incompleteness Theorem can provide a formal version of this verbal argument?

In any case, empiricism supports logic. The reason is as follows: If you assume both empiricism and logic, you can formulate experiments so that, given percept A, you can make a statistical expectation on percept B. This, however, presupposes logic. If we don’t have logic, we have no reason at all to suppose that B will follow A with any degree of certainty. Because we can empirically observe that experiments do bear out, this supports the logical reasoning that we used to make the predictions.

Of course this is far from iron-clad (and even in its weak form does also presuppose logic), but then we can’t really expect too much of an argument that tries to provide evidence for logic itself, now can we?

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Having explained why I think that empiricism is a necessary assumption to make any sense of the world whatsoever, I suppose I should mention—however briefly—why I dismiss alternatives. The most obvious alternative is solipsism, the notion that none of the external world has any reality to it and all you can really know is your own mind. That’s not exactly nonsensical, but it’s not worth considering because it tells you nothing—it won’t get you anywhere. It provides no epistemological framework useful for interacting with anything (if everything you interact with is in your own head, why expect it to behave systematically?). It provides no reason to take logic seriously. It allows you no conclusions.

And, quite frankly, I think that all systems that reject empiricism and scientific thinking suffer of different degrees of the exact same thing. What you claim to intuitively know I may very well intuitively doubt, and if we are to settle it independently—well, we need logic and empiricism. If you claim that reality is somehow subjective and depends on your point of view, that your reality is not necessarily the same as mine, we lack a framework to interact, and it is self-defeating because you have no standing to declare that my view of reality as objective isn’t right (if you do so declare, you are making a distinctly universal and objective claim).

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A logical argument, in its most basic form, looks like A⇒B; A; ∴B. In English: “If A is true, then B must be true; A is true; therefore B is true.” A and B are both propositions, roughly “truth claims”. A is the premise. A⇒B is the inference that drives the argument. B is the conclusion. Now, there are four ways to be wrong:

1. You believe in proposition B without any logical or empirical reason. This is just silly.
2. Your premise is correct (A really is true), but your argument is not valid—A doesn’t necessarily imply B.
3. Your argument is valid, but not sound: Your premise, A, is not actually true.
4. Your premise is false and your argument is invalid.

Note that it is quite possible to go from false premises to a true conclusion, or true premises to a true conclusion via an invalid argument. Reaching a correct conclusion is not proof of sound thinking!

The point of this discussion is that if once you believe in a set of premises and in a conclusion, it’s pretty easy to overlook flaws in the inference. If I know I believe B because A is true, and nothing occurs to gainsay either A or B, I’m not likely to revisit the inference A⇒B with a very critical gaze, because clearly, it worked. However, this is not a reasonable thing to do if this argument is my only reason for believing in B—and since I may have made a mistake in any argument, I should try to be critical of all of them (it may not be my only reason for believing something, but the other reasons may be unsound arguments, so I should treat each one as important). To me, critical thinking lies in scrutinising the premises, but especially of watching inferences very carefully. I pay less attention to conclusions (in a debate, I am unlikely to attack them), because they will flow naturally from the argument if once a sound argument is established.

T.H. Huxley famously said that it was extremely stupid not to have thought of Darwin’s theory of evolution by natural selection. I wouldn’t go quite that far—for several thousand years, countless extremely smart people consistently failed to think of it, until Darwin and (independently) Wallace did so—but I do agree that it is, at least in hindsight, a lot more obvious than those millennia might have us believe.

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Darwin formulated his theory after many years of incredibly extensive and meticulous collection of biological facts. This is invaluable for three reasons—it’s persuasive, it provides detail, and of course it’s necessary to validate it as an empirical science—but I believe that the broad strokes of evolution by natural selection can be deduced from armchair reasoning, armed only with a few basic, biological facts—at least for bisexually reproducing organisms, to which area I shall restrict myself below. Perhaps someone will find that persuasive, and in any case I find the idea interesting enough to consider.

In brief, I believe that we need the following ideas:

• Phenotypic (here, very roughly “biological”) traits are inherited.
• Inheritance of non-acquired traits (trivially observed and deduced).
• The particulate nature of inherited traits (trivially observed and deduced).
• Traits are subject to random variation (long known).
• The Malthusian Argument (accessible to armchair speculators)
• The knowledge of an old Earth

Let’s go through them one by one and see if you agree with my assessment.

First, phenotypic traits are inherited. This has been known for thousands of years—like begets like.

Second, we need the inheritance of non-acquired traits, which I claim is trivially observed. Note (beware of converse error) that I am not saying that it’s obvious that no acquired traits are inherited (and while the “Lamarckian” view of evolution is clearly wrong, there are some things and some senses in which acquired traits can be inherited—by and large, they are not genetic). I’m just saying that some non-acquired traits are clearly inherited. I’m going to call this the Grandparent Argument: Children can inherit traits that clearly run in the family even though such traits may skip a generation. If I share a trait with my grandfather that my father didn’t share, and if this correlation is strong enough to be reliably observed (at some statistical frequency), then the trait can’t be simply acquired, since neither of my parents had it. Yet even though neither parent had it, it was passed down the family: Ergo, there must be something passed down in the blood (actually, of course, the genes).

The particulate nature of genetics is the observation that mixing traits is not just a matter of blending. Let me define my terms: Blending here means that the result is the intermediate of the inputs. If I mix dark blue and light blue, I get medium blue. If I mix “genes for tallness” with “genes for shortness”, I get a person of intermediate height. This was seen as a major problem for Darwin’s theory, once Mendel’s work on genetic became well-known. However, it is, or should be, completely obvious that not all traits work like that. As Dawkins points out, the most obvious way of all is to note that the offspring of a man and a woman is (in a vast majority of cases) a boy or a girl, not an intermediate between the sexes. Other traits are equally obvious; so the children of a blond and a black-haired parent may be either blond or dark, but never intermediate in colour.

Some traits appear to be “blended”. This is because there are lots of “on-or-off” gene “switches”; if my mother has 100 “on” switches for tallness, and my father has 100 “off” switches for tallness, I may end up with 50 “on” and 50 “off” switches and thus, intermediate height. Still, each gene is either the one thing or the other. Genetics is, as Dawkins says, digital. This isn’t exactly obvious—beware again of converse error: I claim that it’s obvious that particulate traits are inherited, not that it is obvious that no “blended” traits are ever inherited.

As for random variation, it’s not hard to deduce from looking at nature—whether by freak mutations, or by observing that minor new traits appear in populations of animals long and well observed, especially populations kept fairly homogenous, such as any kind of livestock, or Darwin’s pigeons.

The Malthusian argument can be very approximately paraphrased as follows: Animals tend to produce more offspring than is necessary to maintain the balance of a population. For instance, half of all geese hatched are female, and each female goose tends to have more than two offspring in her lifetime. Thus, in an ideal population with unlimited food and no predators, the population will increase geometrically—the next generation will be bigger by some factor X (e.g. twice as big); the generation after that, X times bigger again (e.g. twice as big again, or four times the original)—and so on. However, because resources are limited, this can’t go on indefinitely (or there would be infinitely many geese). Therefore, many animals die, and only some survive.

I will gloss fairly rapidly over the existance of an old Earth. Cultural background provides different views on this—some cultures have viewed the world as eternal; some as created within a finite history. In a backdrop of Christian creationism, it is perhaps not obvious that the Earth is in fact several billion years old, and this may have been a big part of the reason why Western science didn’t figure out evolution sooner than it did. Certainly, Darwin and Wallace followed fairly closely in the footsteps of geologists who discovered that the Earth was at the very least many millions of years old. Suffice to say that we now do know, through radiometric dating etc., that the Earth is very old (there’s lots of good evidence for, and no good evidence against this theory), and even if people before Darwin couldn’t account for that from their armchairs, we can.

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Hopefully we can roughly agree on all of the above. My claim is that with this alone, we should be able to hash out a rough view of evolution by natural selection. It goes as follows:

Because we have the Malthusian argument, we know that not animals survive. If an animal has 20 offspring over its lifetime, and its population remains roughly constant, on average less than two of those offspring will survive to leave offspring behind (two, because the animal and on average one mate must be accounted for; less than two because generations overlap). Thus, >(18/20), or >90% of all these animals die without any offspring.

We also know that they vary a little—through random variation, no two individuals are exactly the same (almost every human on Earth carries genetic mutations—you are almost certainly a mutant, dear reader!). Now, by a trivial survival of the fittest argument we can see that who survives and who dies without heirs won’t be completely up to chance. Of course, there’s an element of luck in it. Some animals may be struck by lightning. Sometimes, who gets eaten and who gets away is down to luck.

But “chance” doesn’t differentiate between traits (that’s the point!), and some traits produce some benefit. Maybe the animal that runs slightly faster is better at avoiding predators. Maybe the one with slightly sharper eye-sight is so much better at spotting prey. The difference may be tiny, but there is a difference, and as the experience is repeated over many millions of years, we can see that in the long run, because phenotypic traits are inherited, a beneficial trait will help a “family line” to prosper. (Let me reiterate, because I have seen people have difficulty with this, that random chance does not cancel out these benefits. It’s true that lightning may strike a fast animal as easily as it may strike a slow one…but no more easily. Random chance doesn’t favour the “negative” traits, so there’s still a benefit!)

One argument that was levied against this reasoning about a hundred years ago is that continued breeding will tend to blend a trait into the population, but as we established earlier, inheritance of traits is particulate in nature, so this doesn’t really happen. It should also be noted that because there’s some “particulate pseudo-blending” going on, as also mentioned above, most dramatic evolutionary change happens in isolation—e.g. when a small population (perhaps a pair of animals) is separated from the rest (e.g. insects or birds blown by wind to an island, a herd of deer isolated by a new river…).

We haven’t even gone through my list of basic arguments yet, and already we’ve started to deduce the existence of population genetics.

We’re now ready to show that evolution must be “Darwinian”—Lamarckianism isn’t enough. If you’ve agreed with me all the way, you’ll already see that it plays a part. A second angle on it is to observe that many acquired traits are obviously not inherited—if you lose a limb, or grow a beard, your child will not inherit it. (Even aphids and stick insects, clones of their mothers, inherit the usual number of limbs from maimed ancestors). A third strike against it is that while Lamarckian evolution could (if true) explain some fairly crude traits (stronger arms, longer giraffe necks, etc.), it provides no explanation whatsoever for novel traits—the first ancestor of the eye, a light-sensitive patch, is a novel trait with potential benefits (aid in regulating circadian rhythms, detections of predators who block light sources, etc.), but cannot be explained by Lamarckianism. There must be inheritance of non-acquired traits for evolution to work, and we have already seen that it does.

The armchair argument can’t tell us that nothing Lamarckian happens, but it can and does tell us that Darwinian evolution must happen, and if Lamarckianism is true at all, it’s only in conjunction therewith.

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…And so, hey presto!, we have deduced a very rough outline of Darwinian evolution with only the most basic of facts and observations, quite without the reams of data that Darwin had. Of course it really is extremely rough: We have a crude Darwinian theory, we assuredly do not have Darwin’s!—let alone modern evolutionary theory, which has a century and a half’s worth of evidence, further discoveries, statistics, integration of genetics, and roughly a gazillion other advances on what Darwin, however brilliant, had figured out. I’m sure that a lot of little holes can be poked in it, but I am after all presenting an armchair sketch, not a waterproof argument if you want that, read peer-reviewed books with peer-reviewed references (I purposely avoid giving any links or references precisely to emphasise the armchair nature). As such, I’m not going to bother refuting a lot of the usual arguments against evolution—apart from the fact that most of them are silly, this is just meant to be a rough, quick, and comprehensible (not comprehensive!) positive argument for.

There is one I want to mention briefly, though (apart from the Old Earth bit already mentioned above): It might very easily be argued that my argument lays out a good case for “microevolution”, and someone might seize upon this and exclaim that I haven’t proved “macroevolution”. To this I reply that the distinction between “microevolution” and “macroevolution” is spurious. It is true that biologists may use these terms, but that does not mean that they are distinct categories. “Macro” and “micro” just means “big” and “small”, respectively, and the “two forms” of evolution are the same, unless you can demonstrate that there is an upper limit to what “microevolution” can cumulatively achieve. Otherwise, you may as well agree that a man can walk fifty miles (with rest stops) but refuse to admit that he could possibly walk a thousand, because the former is “microwalking”, which has been observed, wheras the latter is “macrowalking”, which hasn’t and is impossible.

I hope you have found this at least evocative. Please let me know if there are any big, glaring gaps—but leave the little, niggling gaps for Talk Origins or for another time.

In areas like alternative medicine and the anti-vaccine movement, one argument that is frequently brought up is that the status quo looks the way it does because Big Pharma is suppressing the argumentor’s favoured research results—they suppress evidence that vaccines cause health problems because they are greedy and want to make money from vaccines even if harmful; they suppress evidence that homeopathy works because they are greedy and do not want to lose the drug market to homeopaths…

First, let me state quite baldly that I firmly believe that the large pharmaceutical companies fall pretty squarely in the Big Evil Corporation category and frequently engage in questionable or reprehensible behaviour. Certainly many of their executives are as motivated by greed, and as ruthless, as executives of other Big Evil Corporations, like oil companies. I do not dismiss out of hand claims that Big Pharma are doing questionable things. But obviously, that doesn’t mean that they are guilty of all the evils of which they are accused, and we have to look at the actual claims, and corroborating evidence, in order to figure out what’s what.

Frankly, I find the vaccine claim outright puzzling. I have taken vaccines for a number of different things. Every vaccine shot I have taken, even ones I had to pay for entirely out of my own pocket, have cost less than or around $50. Assuming that a vaccine requires one booster shot, that represent a sales potential of $100 for my entire lifetime, a statistical 80 years or so. That’s not a lot of profit.

On the other hand, if vaccines are not available for a disease, the disease has to be cured and controlled. Consider polio, a disease eradicated by vaccines:

There is no cure for polio. The focus of modern treatment has been on providing relief of symptoms, speeding recovery and preventing complications. Supportive measures include antibiotics to prevent infections in weakened muscles, analgesics for pain, moderate exercise and a nutritious diet. Treatment of polio often requires long-term rehabilitation, including physical therapy, braces, corrective shoes and, in some cases, orthopedic surgery.

Portable ventilators may be required to support breathing. Historically, a noninvasive negative-pressure ventilator, more commonly called an iron lung, was used to artificially maintain respiration during an acute polio infection until a person could breathe independently (generally about one to two weeks). Today many polio survivors with permanent respiratory paralysis use modern jacket-type negative-pressure ventilators that are worn over the chest and abdomen.

Suppose that some utterly ruthless Big Pharma executive sits down and does the math on this. We can either sell $100 worth of vaccines to quite a lot of people, but once only per patient lifetime…or, if we make no vaccine available (or allow it to be banned due to spurious health concerns) we can sell antibiotics, analgesics, braces, corrective shoes, surgical equipment, iron lungs…

I don’t claim to be an expert on the market, but I postulate that vaccines just aren’t big money makers compared to after-the-fact treatments, and obviously vaccines compete with curative and palliative drugs. As someone said in agreement with my opinion,

I had a friend working as an assistant on big pharm sponsored vaccine research project back in the early 90s. The pharm company eventually pulled funding for the research, and the researchers suspected that the motivation was that producing drugs to treat the illness in question was a better moneymaker than funding relatively expensive research to develop a vaccine. The vaccine would have essentially killed a bunch of the company's product lines.

Let me make this very explicit: This quote is pure anecdote and is not intended to be used as evidence, but presented as an example of why my argument is plausible. Nor do I have the market research and relative cost/profit analyses for vaccines versus conventional drugs. However, my point is that in order for the “Big Pharma” conspiracy theory to hold any water at all, this argument has to be addressed. In short, conspiracy theorists who view vaccines as poisoning for profit must believe that

1. Big Pharma executives are so ruthless and greedy that they are willing to poison millions of children (including their own) for money;
2. They do this, and get away with it with no sign of internal whistle-blowers (the critics are always outside critics, with no sign of leaked memos as is usually the case in attempts at corporate cover-ups); and
3. Vaccine production is so profitable that even after R&D costs, it earns the company more money than selling curative and palliative treatments.

…And if they wish to be believed, they have to substantiate that.

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Similar claims are often raised by supporters of “alternative” medical treatments like homeopathy and naturopathy. It’s not quite so sinister—they tend to accuse Big Pharma not of mass poisoning campaigns, but merely suppressing their own (surely superior) treatments for profit.

Once again, however, these economic accusations are very fast and loose and vague. Even if homeopathic remedies worked, would it really profit Big Pharma to suppress it? I would rather imagine that they would attempt to take over that market and drive the smaller players out. Simply by pushing for increased regulation (requiring similar standards of evidence of effectiveness and safety for “alternative” drugs as for conventional ones), they would kill a lot of companies that lack the R&D resources to run the necessary studies. (Why don’t they do it already? Well, since these treatments don’t work, the studies would never pass muster.)

Do I know that this is the way the finances would work out? Absolutely not! But the careful evasion of even raising the question makes me think that the alt-med advocates would rather no one think it through—it’s much easier, after all, to go with a knee-jerk Big corporate evil! reaction. There’s no reason to take the greed accusation seriously unless it can be shown to be logically coherent.

This argument has a second irony, of course: Alternative medicine is a huge industry. Billions upon billions of dollars are spent on “alternative” treatments every year—without all the R&D costs that real pharmaceutical companies have to battle with; freed of the expenses and vast time commitments of running large-scale, double-blind medical trials to show that the drugs work. Tu quoque is a logical fallacy, but when the argument amounts largely to character assault (Big Pharma is greedy and evil), it may be worth keeping in mind that “alternative medicine” is no more innocent of the character flaw at hand.

Someone on a forum did me the distinct disfavour of posting the first 20 minutes of the trainwreck film, The Secret, where the “secret” refers to the “Law of Attraction”. Briefly, the idea is that thinking about things will cause them to come about—think about the bad things in life and bad things will happen to you; think about good things and they will happen instead. I’m not going to waste time and space talking about why this is preposterous. What motivates me to write this is rather my anger at this, and what I consider to be the harmful consequences.

Lots of people actually seem to believe in this crap. To some extent, that isn’t too surprising. The facile reasons are, first, that it certainly fits in with a lot of New Age magic; second, that the testimonials look good (the happy supporters they choose to speak out really are happy—of course they are, living in $4.5 million mansions…); and third, it is endorsed by highly visible and respected idiots, like Oprah.

More importantly, however, it ties in very neatly with things that are actually true.¹ Of course positive thinking tends to improve your life in many ways—it’s a well established psychological fact that acting happy tends to make you happier; happiness and confidence improve your interpersonal skills and relations; avoiding focusing on negative things frees you from brooding over misfortunes. None of this validates the “secret”. The fact that your mental attitude is connected to your mental state is painfully obvious, and a positive demeanour improving interpersonal relations (and through that avenue, your life) is only evidence that people respond better to happy, confident people than to sad or aggressive ones, and does not require the existence of some mysterious universal energy found by viciously abusing quantum physics.

All right, then, some hypothetical person might ask, what is the harm? It may be silly, but if it motivates people to engage in positive thinking, which you freely acknowledge is a good thing, then why should we discourage this stuff?

Apart from the fact that I am as dedicated as I am able to pursue truth, and consider it morally valuable in its own right, I do think that this silliness has a very sinister side.

The first and most obvious problem is that when people put their trust in anything that doesn’t actually work, there is a risk that they will eschew real, working solutions because they think they already have one. For instance, the 20-minute clip from The Secret has someone claiming: I’ve seen cancer dissolved.

Let me reiterate that. The Secret strongly implies that positive thinking can cure cancer.

That is when it ceases to be funny. People who swallow this whole are lead to believe that positive thinking suffices to cure cancer. This misinformation can kill. Nothing cures cancer like surgical steel (preferably with chemotherapy and/or radiation therapy as adjuvant therapies to prevent recurrence). Failing to seek proper help can kill you, painfully and horribly.

And, of course, we can extrapolate this to any other medical condition, or for that matter, any other problem.

The second repugnant consequence of this belief in the “Law of Attraction” is that while the film-makers focus strongly on the empowering effect, when positive thinking is believed to change your life, the explicit corollary is that negative thoughts lead to bad things happening. They make this very clear: These people assert not only that negative things will make bad things happen, but that whenever bad things keep happening to you, it is because you are thinking negative thoughts. It’s under your control, they say, and you have the power to change it—but if events are bad, you caused them to happen.

We know, of course, that this is bunk. However, those who believe it are also made to believe that all their misfortunes are their fault. If your house burned down, if you developed cancer, if you were raped—according to the makers of The Secret, this is your fault: You made it happen. This is not only nonsensical, it is also an extremely cruel thing to allege.

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¹ There is a parallel here to the view of some bloggers, such as “Orac”, of “complementary and alternative medicine”, which are perceived to usurp some actually valid ideas, like nutrition and exercise: CAM practitioners prescribe good nutrition, exercise, and homeopathic remedies; good nutrition and exercise are clearly good for your health; therefore homeopathy must be good—stated so baldly, the intellectual bankrupcy of the notion is obvious.

Autism is a pretty mysterious condition. No one really knows what causes it (all we really know for sure, after all this testing, is that whatever else it does, the MMR vaccine definitely doesn’t cause it…), but it’s thought to be part genetic, part environmental. A Swedish study on indoor air pollutants has now suggested that, although the data are very tentative, vinyl flooring may increase the risk of autism!

The researchers found four environmental factors associated with autism: vinyl flooring, the mother's smoking, family economic problems and condensation on windows, which indicates poor ventilation.

Infants or toddlers who lived in bedrooms with vinyl, or PVC, floors were twice as likely to have autism five years later, in 2005, than those with wood or linoleum flooring.

Whether the link is real is, as the researchers very frankly point out, as yet unknown, and only further studies can reveal it. I find this interesting to consider, however, as a case study in how easy it is to get the wrong impression from results like these. There’s a number of interesting traps to fall into.

1. It’s fairly likely that someone will report on this, or already has, under a headline like Research finds link between vinyl flooring and autism, giving the impression that it’s clear-cut, whereas the single most clear-cut message of this study is that it ain’t so.

2. Correlation does not imply causation, and even when there’s causation, we have to make sure we get it the right way around. As one commenter to that article pointed out, autistic children tend to be extremely preoccupied with textures. Even if there’s a direct link between vinyl flooring and autism, that doesn’t mean that the former causes the latter. Maybe families with autistic children prefer vinyl flooring because it makes the children happier, and so in a sense, autism might cause vinyl flooring!

3. Notice that they found four, that’s four environmental factors associated with autism: vinyl flooring, the mother's smoking, family economic problems and condensation on windows. However, these variables were not controlled for, and may not be independent.

   What does this mean? Well, it may be that any or all of these variables are connected: Maybe poorer people are more likely to smoke, less likely to afford good ventilation, and less likely to afford nice hardwood floors. If any of these things really does increase the risk of autism, the other variables will be associated with it: If, say, the mother’s smoking causes autism, and more poor mothers than wealthy mothers smoke, then vinyl floors and everything else associated with poor people shows up as associated with autism in the statistics. But while the correlation is there and is real, there is (in my example) no causative relationship at all.

   This sort of thing is always a problem with any studies, especially (I believe) when randomisation is poor or sample sizes are small. These are four known and named variables that may reasonably be correlated. What would we have thought of this article if they hadn’t mentioned smoking, wealth, or ventilation? It would have painted a very different picture. And it’s not necessarily dishonesty or editorial brevity that leaves variables out of the equation: Sometimes relevant data just aren’t measured—what if the study hadn’t asked about wealth or smoking?

   I’m reminded of the very poorly thought-out article I read a little while back that claimed that light pollution at night from all the street lights and so forth lead to—I don’t recall: Some health problem or other. However, light pollution goes with industrialisation, and the number of variables you introduce when you compare a more industrial to a more agricultural country is ridiculously large. The article made no mention of those at all, but spoke as though there had to be a direct causal link from light pollution to the health issue at hand (which is why I consider it such a poor article).

4. The study was not designed to look for these data, which means that we must suspect data mining. Data mining refers to digging through a set of data looking for any relationships, whether the ones originally examined or not. The problem is that some relationship will always be found.

   Suppose, for instance, that a study is in some global sense 99% reliable. What does this mean? It means that we set out to discover whether X causes Y, and if the study says yes, we can be 99% certain that we’re right. On the flip side, there’s a 1% chance that we’re wrong. Now suppose that, since we have all these statistics anyway, we decide to check of X causes Z, or A causes B…and so on. For every single one of these, we may (very generously) be 99% certain that it’s correct, but if we look for 100 different relationships, we know that we’ve probably got at least one wrong!

   In fact, we’re 73% likely to have got at least one wrong, and that’s with a 99% confidence level and the very generous assumption that the data are as reliable in unknown areas. In reality, I expect that will often not be the case: Even if I design my study to control for a lot of variables surrounding the hypothesis I set out to explore, I can’t possibly do the same for a bunch of hypotheses someone constructs from my data after the fact.

   This is why data mining is frowned upon in scientific studies. We can look at data like that and find correlations that intrigue us, and use those correlations to inspire new studies—just as this Swedish study means that it might not be a bad idea to look at possible connections between vinyl flooring (and phthalates) and autism…but we shouldn’t be fooled into thinking that they necessarily mean anything, because we know that if we look hard enough at any set of statistics, we will be able to find some spurious connections.

“Orac” over at Respectful Insolence has a writing style that’s fairly prone to offend—definitely pugnacious, and very fond of side swipes at those he dislikes (primarily alternative medicine quacks)—and I don’t blame him for his distaste, which in fact I share, but it does sometimes make his essays a bit harder to slog through. (He also has an inordinate fondness for beginning sentences with Indeed. This is one area where I can tentatively claim superiority: I can also be pugnacious and come off as offensive, but while I am no less prone than Orac to complicated sentence structure, I’ve never been accused of any such repetitive verbal tic.)

However, those foibles aside, he has written some very good stuff (he’s on my list of blogs I ready daily for a reason), and this article, summarising and explaining the work of a John Ioannidis, was very interesting indeed. The claim it looks at is a very interesting and puzzling one: Given a set of published clinical studies reporting positive outcomes, all with a confidence interval of 95%, we should expect more than 5% to give wrong results; and, furthermore, studies of phenomena with low prior probability are more likely to give false positives than studies where the prior probabilities are high. He has often cited this result as a reason why we should be even more skeptical of trials of quackery like homeopathy than the confidence intervals and study powers suggest, but I have to confess I never quite understood it.

I would suggest that you go read the article (or this take, referenced therein), but at the risk of being silly in summarising what is essentially a summary to begin with…here’s the issue, along with some prefatory matter for the non-statisticians:

A Type I error is a false positive: We seem to see an effect where there is no effect, simply due to random chance. This sort of thing does happen. Knowing how dice work, I may hypothesise that if you throw a pair of dice, you are not likely to throw two sixes, but one time out of every 36 (¹/₆×¹/₆), you will. I can confidently predict that you won’t roll double sixes twice in a row, but about one time in 1,296, you will. Any time we perform any experiment, we may get this sort of effect, so a statistical test, such as a medical trial, has a confidence level, where a confidence level of 95% means there’s a 5% chance of a Type I error.

There’s also a Type II error, or false negative, where the hypothesis is true but the results just aren’t borne out on this occasion. To the best of my knowledge, there is no equivalent of the confidence level for Type II errors.

This latter observation is a bit problematic, and leads into what Ioannidis observed:

Suppose there are 1000 possible hypotheses to be tested. There are an infinite number of false hypotheses about the world and only a finite number of true hypotheses so we should expect that most hypotheses are false. Let us assume that of every 1000 hypotheses 200 are true and 800 false.

It is inevitable in a statistical study that some false hypotheses are accepted as true. In fact, standard statistical practice [i.e. using a confidence level of 95%] guarantees that at least 5% of false hypotheses are accepted as true. Thus, out of the 800 false hypotheses 40 will be accepted as "true," i.e. statistically significant.

It is also inevitable in a statistical study that we will fail to accept some true hypotheses (Yes, I do know that a proper statistician would say "fail to reject the null when the null is in fact false," but that is ugly). It's hard to say what the probability is of not finding evidence for a true hypothesis because it depends on a variety of factors such as the sample size but let's say that of every 200 true hypotheses we will correctly identify 120 or 60%. Putting this together we find that of every 160 (120+40) hypotheses for which there is statistically significant evidence only 120 will in fact be true or a rate of 75% true.

Did you see that magic? Our confidence interval was 95%, no statistics were abused, no mistakes were made (beyond the ones falling into that 5% gap, which we accounted for), and yet we were only 75% correct.

The root of the problem is, of course, the ubiquitous problem of publication bias: Researchers like to publish, and people like to read so journals like to print, positive outcome studies rather than negative ones, because a journal detailing a long list of ideas that turned out to be wrong isn’t very exciting. The problem is, obviously, that published studies are therefore biased in favour of positive outcomes. (If not, all 800 studies of false hypotheses would have been published and the problem would disappear.)

Definition time again: A prior probability is essentially a plausibility measure before we run an experiment. Plausibility sounds very vague and subjective, but can be pretty concrete. If I know that it rains on (say) 50% of all winter days in Vancouver, I can get up in the morning and assign a prior probability of 50% to the hypothesis that it’s raining. (I can then run experiments, e.g. by looking out a window, and modify my assessment based on new evidence to come up with a posterior probability.)

Now we can go on to look at why Orac is so fond of holding hypotheses with low prior probabilities to higher standards. It’s pretty simple, really: Recall that the reason why we ended up with so many false positives above—the reason why false positives were such a large proportion of the published results—is because there were more false hypotheses than true hypotheses. The more conservative we are in generating hypotheses, the less outrageous we make them, the more likely we are to be correct, and the fewer false hypotheses we will have (in relation to true hypotheses). Put slightly differently, we’re more likely to be right in medical diagnoses if we go by current evidence and practice than if we make wild guesses.

Now we see that modalities with very low prior probability, such as ones with no plausible mechanism, should be regarded as more suspect. Recall that above, we started out with 800 false hypotheses (out of 1000 total hypotheses), ended up accepting 5% = 40 of them, and that

It's hard to say what the probability is of not finding evidence for a true hypothesis because it depends on a variety of factors such as the sample size but let's say that of every 200 true hypotheses we will correctly identify 120 or 60%. Putting this together we find that of every 160 (120+40) hypotheses for which there is statistically significant evidence only 120 will in fact be true or a rate of 75% true.

That is, the proportion of true hypotheses to false hypotheses affects the accuracy of our answer. This is very easy to see—let’s suppose that only half of the hypotheses were false; now we accept 5% of 500, that is 25 false studies, and keeping the same proportions,

…Let's say that of every 200 500 true hypotheses we will correctly identify 120 300 or 60%. Putting this together we find that of every 160 (120+40) 325 (300+25) hypotheses for which there is statistically significant evidence only 120 300 will in fact be true or a rate of 75% 92% true.

We’re still short of that 95% measure, but we’re way better than the original 75%, simply by making more plausible guesses (within each study, we were still equally likely to make either Type I or Type II errors). The less plausible an idea is, the higher the proportion of false hypotheses will be out of all the hypotheses the idea generates: A true/false ratio. Wild or vague ideas (homeopathy, reiki, …) are very likely to generate false hypotheses along with any true ones they might conceivably generate. More conventional ideas will tend to generate a higher proportion of true hypotheses—if we know from long experience that Aspirin relieves pain, it’s very likely that a similar drug does likewise.

This is not to say that no wild ideas are ever right. Of course they sometimes are (though of course they usually aren’t). What it does mean is that not only should we be skeptical and demand evidence for them, there are sound statistical reasons to set the bar of evidence even higher for implausible than for plausible modalities.

It is also a good argument for the move away from strict EBM (evidence-based medicine) to SBM (science-based medicine) where things like prior probability are taken into account. Accepting 95% double-blind trials at face value isn’t good enough.

Skeptical blogger Ziztur has a little project called Ray a Day wherein she (with the assistance of her boyfriend) go through one question a day from Ray Comfort’s book, You Can Lead an Atheist to Evidence, But You Can’t Make Him Think: Answers to Questions from Angry Skeptics. The other week, she circulated an email among her awesome commenters, in which number I have been granted the honour of inclusion.

Here’s my contribution, wherein I address Ray’s “answer” to a question challenging the existence of Hell, and muse a bit on the motivation underlying such unapologetic apologetics. Go read it, then read the rest of Ziztur’s blog.

Although I’m currently reading Don Quixote, I needed a book this weekend that was physically small enough to fit in my coat pocket, so I have re-read Crichton’s Jurassic Park. Much more involved in scientific detail and discussion than the movie, I always enjoy reading it: It has people being eaten by dinosaurs and it’s thought-provoking; what’s not to love?

There is another side to it, however. To a much greater degree than the movie, partly in its description of the book’s scientists like Dr. Wu, and partly in the commentary by Ian Malcolm, it acts as what I can most charitably describe as a ‘cautionary tale’. Less charitably, it comes off as anti-scientific: Dr. Malcolm explicitly describes science as an outdated and doomed mode of thinking, and the turn of the story gives the impression that his is the message that Chrichton wanted to deliver¹. (From what I have heard of some of his other books, that’s not uncharacteristic of Crichton’s thinking and writing.) As a great fan of reason and scientific thinking, I don’t much like that message, but on the other hand (and for the same reason), it would be irresponsible of me not to at least think about it.

The gist of the story is of course extremely simple: Scientists attempt to play god, things go terribly wrong, they are terribly surprised, and bad things happen. In such brief terms I can hardly fault it. Scientists are just people, after all, with varying motivations; and they work for people who also have varying motivations. Sometimes things go very wrong, and with the power of what Crichton has Dr. Malcom refer to as inherited power, the consequences can today be very far-reaching indeed. But I take exception to this message on two points.

One is that the message presented is that scientific thinking leads to disaster, but the message delivered by the actual plot of the book is that science in the hands of irresponsible con men (like Hammond) and immoral businessmen leads to disaster. That’s fair enough and a point both more nuanced and more true: Science has given us great power for good or for evil, and we must wield it responsibly—but science itself, and scientific inquiry and knowledge, is no more moral or immoral than any other tool. A hammer can save lives in helping to build shelter, or it can be wielded as a lethal weapon, but the hammer itself is neither good nor evil: It’s just a tool. Just like a hammer, science has no inherent morality, and does not make claims to it. Science is a tool for finding the truth about reality—ultimately, what the scientific method is, is an astonishingly wonderful way of arriving at accurate claims of the form If X, then Y. I don’t mean to say that it has no applicability to moral decisions. On the contrary, it is essential, in that we cannot make good moral decisions unless we attempt to predict the consequences of our actions. But ultimately, science tells us what’s likely to happen given certain events and conditions. It doesn’t tell us what should happen. We always have to establish some arbitrary, subjective ground case, a premise for our reasoning—Human happiness is good, It is better to be truthful than to lie, All people are morally equal unless they forfeit that standing by working evil. This is not novel, and no scientist or scientifically inclined person I know has to my knowledge claimed otherwise. This is why we claim to be things like humanists, which does establish a moral basis.

My second objection is that while Crichton appears to rail against science as an endeavour, but the novel serves as a critique against bad science, science executed naïvely. This is of course a fair point, too, but again the message preached and the message delivered don’t seem to be the same. When Dr. Malcolm vehemently insists that the Jurassic Park endeavour is doomed to failure due to the unpredictability inherent in biological systems and predicted by chaos theory, he is leaning on scientific findings (referring, though not by name, to Edward Lorenz’s discovery in attempted weather prediction). But the failing to consider this is not an inherent problem of scientific thinking at all; it’s a failure to use scientific thinking more sophisticated than a Newtonic clockwork universe². We know about chaos theory; we know about intractable problems; we certainly know about error bars.

As this was percolating in the back of my mind, I came across an interesting post by Erin with an even more interesting comment to follow: In brief, pointing out the complexity and difficulty of addressing so apparently simple a question as What is the proportion of land (times their potential yield) suitable for growing crops, as compared to land suitable only for raising animals? —Which I asked, ignorant of the ill-posed nature of the question itself, and how many variables I had failed to control just in asking a question. Here’s a real-world example of a question with every implication of the unpredictability of nature, not to mention ecological consequences (how humanity does agriculture is clearly very significant). (It comes from an unsurprising source: Erin seems to have a knack for raising questions that strike me as good, interesting, and challenging without ever wandering into wingnut territory. It is a valuable knack to have.)

But this unpredictability, the difficulty in even asking the right questions, the limitations of our ability to predict the behaviour of chaotic systems when we cannot measure the variables sufficiently closely or often—none of this means that science is therefore any worse a mode of thinking; on the contrary, science done right comes with error bars and attempts to find its own limitations; a hunger for the unanswered questions. A scientist is never someone who thinks that everything worth knowing is already known—if it were, every scientist on Earth would be out of a job. A scientist is someone who wants to identify areas of ignorance, try to ask the right questions, and find the answers.

And—as always when someone criticises science as a mode of thinking—what else should we rely on? It is true that science today can’t tell us what will happen if we clone dinosaurs, or if we adopt this or that method of agriculture, on a large scale and in the long run—but no other form of knowledge acquisition can even begin to help us, and we cannot go back. (Anyone who thinks that only modern, large-scale agriculture has the potential to harm our environment needs to read Jared Diamond and stop blindly romanticising the past.) Don’t criticise the tool: It is the best, the only tool we have for addressing those issues to which it is applicable. If you wish to leverage criticism, criticise those who use the tool wrongly, who approach it with the wrong presuppositions or premises, who apply it naïvely.

The notion that science as a way of thinking is doomed and a failure strikes me as nothing less than ridiculous and absurd. We don’t need a replacement for it, and whether we want or no, it is too late to go back now. What we may need is a value system and a socio-cultural framework better able to handle it.

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¹ I will continue to treat this as if the character of Dr. Malcolm expresses Crichton’s opinions. I don’t claim to know for sure whether he does. At any rate, this is the message that was communicated to me, whether intended or not, and it is the message I want to address.

² Within the context of the novel, it’s also the result of an awful approach to security. Any computer programmer worth his salt knows that you should never assume that things go wrong, and look for specific, predicted problems; rather, you should assume that things will go wrong, and compare input to specific, predicted, correct values or formats. To name a detail, if the programmers in the novel hadn’t made the very foolish decision of assuming that the number of animals found would ever exceed a given number and stop counting at that point, the unexpected breeding would have been found out.

As someone who values the scientific method and philosophy of logical inferences and dedictions, empirical observation, Occam’s Razor, and so forth with a rather long list of highly valued principles; as someone who thinks that few approaches to finding truth can compete with experiments in physics, or double (or triple!) blinded medical experiments (when evaluated as Science Based Medicine [SBM] rather than Evidence Based Medicine [EBM], with the former’s greater understanding and acknowledgement of prior probabilities, etc.)—

—As a naturalist, materialist skeptic, in other words, one of the most irritating and most pernicious cognitive traps is that of scientific-sounding rationalisation, that isn’t science at all. I daresay it’s something several people I have talked to (or do talk to) would accuse me of, had they happened to express themselves using my exact vocabulary (though it isn’t their entire beef). I do acknowledge that it’s real; I do not claim to be immune to it; I do my best to guard myself against it. …But what am I actually talking about? What is the basis for my worldview, what are the common errors and how do I try to guard against them; what are the inherent weaknesses, and how to I justify adhering to this mode of thinking in spite of them?

What science is

Science is a process of finding the truth¹ by

1. Making observations (gathering data);
2. Constructing a model (forming a hypothesis);
3. Making predictions based on the model;
4. Verifying the predictions, and throwing out the model if it’s wrong.

Of course that’s a very rough generalisation, but that’s the basic idea: You need data to construct a model; you need a model to generate predictions; and if you don’t have any verified predictions (which means they must be falsifiable! —it’s not verified unless you leave room for failure if the model’s wrong), it isn’t science.

Scientific explanations aren’t like that, though. A scientific explanation of an already-observed phenomenon is not science; it’s just based on it. It cannot be science: In order for it to be science, I need to construct a model and check that it’s a good model. We don’t always do this when we explain something scientifically. Instead, a scientific explanation is an explanation of some phenomenon or occurrence based on what science has shown is feasible. If you show me an example of purported levitation, or a UFO sighting, or similar, and I explain (very reasonably and probably correctly) that there are natural explanations for what I’ve seen, I’m just observing that it fits the current scientific models.

Post hoc rationalisation

The real problem, here, enters the picture when we try to construct models and treat them as scientific models relying completely on post hoc data—and the difference can be a subtle one. The problem is that it is impossible, without generating and testing predictions, to know whether the model is actually correct, or merely happens to apply to the data at hand—which may be woefully incomplete, subject to natural selection bias or (more sinisterly) to cherrypicking.

This is a problem not just in discussions where people attempt to sound scientific, but also historically with science itself—very notably before the modern scientific method was formulated. People who don’t trust the scientific way of finding the truth are often fond of pointing out egregious pseudosciences that were, in their own time, respected and considered as scientific as anything else. Whether the balance of humours, the theory of miasms, the notion of the luminiferous æther, phrenology, or any other such now-discredited concept (I almost said homeopathy, but it never really did have that sort of credibility), they once did serve as models to explain all the data compiled into their construction—but all of them were wrong, and were able to survive because they were not used to generate and test falsifiable predictions. …Survive for a while, that is: By now all of the above are discredited because we do know better; and sometimes, to their credit, it is the proponents of ideas that discover and publish the fact that the ideas are wrong; as with Michelson and Morley and their famous æther experiment.

Let me be very clear and explicit in saying that if you cannot generate and test predictions, it is never science in the true sense, however reasonable your explanation. (Note that prediction refers to a prediction of what we will find—in historical and palæontological sciences, the events happened long ago, but we can still make predictions about what new data will discover; hence that famous prediction in palæontology that we will never find a Cambrian rabbit fossil.) This is why interpretations of quantum physics are metaphysical rather than physical, since they do not make different predictions. (On a not unrelated observation, I despise the term string theory—it is string hypothesis until predictions are tested!)

Equivocation

As with any profession or culture, science is full of very technical jargon. Many of the most awful abuses of science I have come across have been straightforward instances of equivocation. The most infamous is, of course, the creationist’s claim that evolution is just a theory, apparently unaware that an explanatory framework in science can have no higher title. (Some would have it that if evolution were proven, it would be the law of evolution, but that’s just not true: Explanatory frameworks are never elevated to laws, no matter how solid. To quote Stephen Jay Gould,

Evolution is a theory. It is also a fact. And facts and theories are different things, not rungs in a hierarchy of increasing certainty. Facts are the world’s data. Theories are structures of ideas that explain and interpret facts. Facts do not go away when scientists debate rival theories to explain them. Einstein’s theory of gravitation replaced Newton’s, but apples did not suspend themselves in mid-air, pending the outcome. And humans evolved from ape-like ancestors whether they did so by Darwin's proposed mechanism or by some other yet to be discovered.

Another favourite term to pervert and subvert is that of energy, which quantum quacks gleefully use as though I feel full of energy were related by an equation to E=mc²—when in fact energy in physics is a strictly and technically defined term, related to the colloquial word by etymology and analogy, but no more. Force suffers similar abuses.

Now, I’ve used pretty obvious examples, but equivocation can actually be pretty difficult to detect when used skilfully, and it can lead to genuine misunderstanding. The equivocater’s trade lies in

1. equivocating using such language that the equivocation is not obvious (i.e. it looks as though the technical sense might apply on both sides of the equation); and/or
2. couching the equivocation in a discourse sufficiently technical that the reader (or listener) just isn’t qualified to tell them apart.

The latter is particularly pernicious because the same word may mean different things in different contexts, or have different definitions in the jargons of different fields. Apart from education (which sounds like such a good idea, but really, you can’t be well educated in everything) and listening very carefully, about the only way I know to avoid this sort of thing is to make sure that anyone who claims that two things are mathematically related can actually show the form of the equation.

Non sequiturs, red herrings, and other fishy things

Another problem, less subtle than true equivocation and more easily countered, but nonetheless a cause for vigilance and concern, enters the picture when the model is (or may be) complete, but the relevance hasn’t been established. One example I see very frequently indeed is in the context of the martial arts message boards I frequent, where every so often someone will attempt to validate his (usually arcane) form of martial arts as having the superior form of punching by using not fight records (showing that his stylists can beat up other stylists) but physical equations—attempting to show, for instance, that this method really does maximise the momentum transfer of a punch. Maybe so; maybe not. The problem here is that it was never shown that maximising the momentum transfer is really what makes a punch most powerful; the next person with the next martial art will instead present some half-arsed equations showing that he can maximise force—or impulse, or velocity, accoleration, jerk, pressure, or other physical property. It may be some time before anyone steps back from trying to disprove the equations to realise that it’s a non sequitur.

In short, one must not fall victim to the belief that just because someone backs up a claim with a scientific-sounding argument, that argument necessarily supports the claim. It is a requirement of a valid logical argument that the conclusion necessarily follows from the premises—but this has to be established; it cannot simply be assumed.

In defence of Occam’s Razor

Occam’s Razor is the philosophical principle that out of any set of explanations, the simplest is always to be preferred:

Numquam ponenda est pluralitas sine necessitate.
(Plurality must never be posited without necessity.)

Frustra fit per plura quod potest fieri per pauciora.
(It is futile to do with more things that which can be done with fewer.)

William of Ockham

My own favourite formulation runs somewhat as follows:

Given two explanations of a phenomenon, all else being equal, choose the one that requires the fewest assumptions.

This always looks like a suspect—why should we prefer the simpler explanation? Aren’t explanations of things sometimes genuinely and necessarily complex? How on Earth can you justify basing a depiction of reality on something so vague and susceptible to error?

The answer to this is twofold. First, note my inclusion of all else being equal—of course if we have two explanations for a set of phenomena, both of which generate testable predictions, and one of them produces significantly better fits to newly observed data, that’s a pretty good case to support this one even if it’s more complex. Occam’s Razor isn’t to be used as an excuse to throw out superior models.

Secondly, it is an unfortunate fact that for any phenomenon, you can generate an infinite number of explanations by making them increasingly complex. A simple example is found in every statistics class, where we find that anytime we try to fit a polynomial curve to a set of data points, we can always achieve an equally good or better fit by increasing the order of the polynomial (making our explanation more complex). In fact, more complex explanations are here usually better fits to the data, because the data have measuring errors and so don’t fit exactly to the predicted curve of the right explanation, whereas a very high-order (complex) polynomial can jitter up and down to match every blip in the data.

It should be pretty clear that we can’t get very far if we attempt to maintain an infinite number of explanations for everything we try to explain. Instead, we choose the simplest explanation that works and resort to more complicated ones only if it turns out that the predictions we get from our simpler models aren’t up to snuff. Of course, this process is empirical—we may find out only in time that our model has shortcomings. Unfortunately, it’s the only way we have to proceed; it would be nice if we had some more absolute way of finding out truth, but we don’t. (This is why it is often said of science, properly done, that it tends to approach the truth asymptotically—it can never reach an unassailable, absolute position of Truth, but every subsequent model, because it has to account for all the data that the old model did explain, as well as the data that we’ve found the old model fails to explain, is a better model than the last.)

A more colloquial sort of defence of Occam’s Razor is to observe that it is the principle whereby we explain the world in terms of things we know to be possible, rather than positing arbitrarily things that we don’t know have even a chance of being true. In an example that I freely acknowledge to be something of a reductio ad absurdam, if I leave some chocolate on the table next to a child, turn around for a minute, then return to find the chocolate gone, and the child claims that he did not eat it, but rather that the chocolate was teleported away by aliens for scientific study, I would be an idiot to believe him—not because it is absolutely impossible, but because one explanation (he’s lying) rests on observably possible things (children sometimes eat chocolate; children sometimes lie), whereas the other postulates something (the existence of aliens with teleportation technology) for which there is no evidence.

Jumping from that insultingly trivial example to something that actually is a matter of debate, some people claim that the human mind cannot be the product of the brain alone, but must also rely on something called a soul, or other immaterial and scientifically undetectable entity that is not a product of material causes. Here, the naturalistic explanation is a lot less obvious—we cannot at present show how the mind results from the brain. Some would also argue that the alternative explanation (there is a soul) is less absurd than the alien hypothesis (though I would disagree).

The difference, however, is purely quantitative. We know that brains and minds are very intimately connected—we can observe the mental and psychological effects of damage to the material brain, artificial or natural alterations of brain chemistry, et cetera; we can scan activity in the physical brain correlated with thoughts and emotions; we can view the material development of the brain from embryo to developed organ. The assumption in the naturalist model is just this: That in a complicated neural network consisting of a hundred billion neurones, with feedforward and feedback loops, and modulated and assisted by glial tissue and chemical catalysts in the form of neurochemicals; in such a network that has, furthermore, evolved by fairly well-understood principles of natural and sexual selection, sufficient complexity has arisen to explain the minds that we now experience.

The soul hypothesis may look simpler because it can be summarised more briefly, but its assumptions are actually huge. It postulates the existance of something for which we have no evidence whatsoever—the materialistic hypothesis is complex, but it rests on established facts. Furthermore, it postulates that this intangible soul—which no scientific instrument has been able to detect—is yet able to exert causal effects on the material brain, since it is very clearly established that it is in the brain that our motor impulses originate. (René Descartes thought that the soul operated on the brain through the pineal gland.)

It also suffers the difficulty that if we be allowed this one, completely unfounded assumption (there exists a soul), it is difficult to see why we should disallow any unfounded assumption as a valid rival, so long as it is not falsifiable; for instance, I might equally well claim that your brain is run by a computer program (written by aliens, or the NSA, or the Illuminati); that you are mind controlled by the White Mice… These sound more ridiculous to us, but that is a cultural artefact. The Soul Hypothesis and the White Mice Hypothesis have an equal basis in evidence.

I daresay that William of Ockham, a Franciscan friar, would disagree with my conclusion; but while I think that his beliefs were most likely pretty absurd, I nevertheless think that his principle of parsimony is a necessary part of a rational worldview.

Occam’s Razor or rationalisation?

When I get involved in discussions or debates questioning this worldview and philosophy of mine, and (this is, alas, a limited subset) when the person I am conversing with is neither stupid nor patently insane, one of the most common and most reasonable objections runs something like this (in spirit; I reformulate rather than paraphrase):

What you say generally makes sense, but because the philosophy ultimately relies on empiricism in determining what’s real and what’s not, it is—as you acknowledge—imperfect, and unless you end up clinging dogmatically to your skeptical beliefs (contrary to your own philosophy) you are bound to change your mind on things as new evidence emerges.

Well, given that, by what right do you reject (for instance) the soul concept so strongly? You may think that there is no evidence, but evidence may come up, and you certainly have no strong counterevidence. Why not just keep an open mind?

…As, of course, I should, but as the saying goes, You should keep an open mind to new ideas, but not so open that your brains fall out. It should be noted and emphasised that when I say There is no such thing as a soul, what I mean is To the best of my knowlege, and according to the best evidence and reasoning available, there is no reason to think that there exists such a thing as a soul. (Whether I am truly as open-minded as I should like to new evidence in the areas where my worldview is heavily invested is, of course, hard to say; but I’m defending the way I try to structure my thinking, not rating how well I measure up to my own ideals.)

Ultimately, I regard this as a quantitative rather than a qualitative distinction. It is not whether I am willing to credit the possibility of some improbable concept or not, but just how large or small a probability I am willing to credit it with. My own tendency and preference is to treat extremely improbable things (souls, færies, ghosts, celestial teapots, alien abductions, gods, Great Green Arkleseizures, effective reiki or homeopathic remedies, etc.) as so improbable that unless better evidence or arguments are presented, I will not bother with the possibilities of their reality at all. I will freely acknowledge that they are non-zero, in the absolute sense, but it’s such a small one (0.00…01%) that it’s not worth bothering with. This is, of course, where I often and easily come off as contentious or even contemptuous, and people whose approaches otherwise look similar to mine may differ in how small a prior probability we should assign these things. (If you want a gentler version, read the late, great Dr. Carl Sagan’s The Demon-haunted World.)

Of course, being but a human, I’m very likely to be wrong about a great many things, some of which may very well be of fundamental importance to my worldview. If we were to line up all the things I consider to be ludicrously improbable, I expect that, due to human fallibility and my own sometimes unfortunate tendency to over-swift rejection of apparently unscientific notions, I will be wrong about a number of them. But I consider the probability of my being wrong on any specific such matter to be very small. In the end it comes down to whether I would rather say Well, maybe to everything I come across, or whether I’m willing to say Yes and No and be prepared to eat my hat when the day comes when I turn out to be wrong. I’m willing to do the latter (against which occasion I cleverly do not wear a hat). To me, there’s no other sensible way to proceed. If I accept the soul hypothesis as likely enough that I shouldn’t reject it utterly out of hand, I cannot remain intellectually honest and consistent without accepting any number of other such claims—UFOs, homeopathy, reiki, unlucky black cats, astrology, and all the rest.

I would rather be forceful and intellectually honest and consistent, and occasionally be wrong, than either waffling about every incredible claim anyone cares to make, or arbitrarily accepting improbabilities based solely on their cultural or social acceptability.

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¹ Some people hold that hunches and intuition are as good guides to truth as is scientific inquiry; to which, apart from obvious retorts (Would you rather travel on an airplane built according to scientific principles, or on one based on intuited ærodynamics?) I would like to reply that whenever a hunch is opposed to reason, I have a hunch that reason is right; so hunches cancel out and we’re left to trust to reason².

² Unless you belong to that school of thought that claims that there is no such thing as objective reality; that all reality is subjective. I have a vast dislike for such solipsism, but I suppose I can’t deny you your subjective reality; in my reality, however, things are objective and that school of thought has no value or standing.

The other day, someone told me that I treated science as a god replacement—in fact, two people who more or less know me had apparently been talking about me in those terms. I’m still trying to figure out whether that’s a good thing or not, apart from the blind faith connotations inherent in the religious terms (to my ears, at least).

The key is, of course, to nail down exactly what one means by science. I do not think that any scientific fact should ever be held as gospel—many are solid beyond the shadow of a doubt, but new facts, new lights, may cast new shadows. Obviously, I do not wish to deify any scientist. There are many scientists whose minds and accomplishments I admire (and while some, like Sir Isaac Newton, were awful human beings, others, like Charles Darwin, seem to have been very good people morally as well as intellectually), but they are or were human and fallible. Not only am I unconcerned by ad hominem arguments (Newton's being a right bastard doesn’t detract from his intellectual achievements, or make his theory of universal gravitation any less useful); I also am not bothered by any scientist being shown to have been wrong on any particular point.

This may not always be obvious in conversation and debate, of course. I’m rather fond of putting it so: When I am convinced that something is sufficiently probable that the margin of error, though never zero, is negligible for practical purposes—e.g. I am so convinced of the truths of gravity, electromagnetism, evolution, etc. that I see no reason to take the null hypotheses into consideration—I choose to say that I know it is so, because it is shorter, more forceful, and more pithy than I am convinced that the probability of it being so is so high as to render the null hypothesis negligibly small for practical considerations, even though the latter more accurately describes the stance I try to take.

There is also the lamentable fact that I’m stubborn and like to argue and have an all-too-human tendency to take a position with overtones of fiendish advocacy: If you take a position that I disagree with, I may for the sake of argument take an opposite position more extreme than I truly credit.

That aside, what’s left is not scientific fact, nor scientific practitioners, but science itself. Thus, either people who look at me and cry God replacement! misunderstand me and think that I deify scientists or scientific facts (which may be my fault as easily as it may be theirs), or it is science itself that is the issue at stake. It may well be the latter. But science is not a set of facts, or of people, though it needs these things: Science is a method and process of discovering truth based on logic, empirical observation, mathematics, statistics, probability, and naturalism. (This is not to say that science is by definition incapable of discovering supernatural phenomena—if any exist, they will be found precisely where science finds anomalies that cannot be accounted for under the assumption that these rules all hold.) It is the only method we have for discovering the real truth of the universe to any degree superior to our own brains, which, for all that they are marvellous pattern-recognising deduction machines, are also prone to finding false patterns, pareidolia, conflating correlation with causation, and many other errors that we should expect from an animal that pays a much more dire prize for false negatives than for false positives, and whose heuristics have limited powers.

I asked someone recently in a rather pointed way whether she felt that intuition was as good a guide to truth as scientific inquiry. She replied (you’re going to think I’m crazy, but…) that she does, because scientific models are always constrained by prevailing cultural and intellectual paradigms. In some areas of research, this may have a point, but I think it misses the main point entirely, because this is precisely what science is meant to avoid. If you can point out a way in which a study—any study—has a risk of being less than objective due to such biases, you have not poked a hole in the scientific method in general, but rather identified another bias for high-quality scientific inquiry to correct for—along with logical fallacies like conflating correlation with causation, confirmation bias, observer effects, the Hawthorne effect, regressions to the mean, placebo effects in medicine, and myriad other cognitive quirks that we have to isolate.

But the highest goal of science is to find objective truth, and I don’t care what you say—unless you subscribe to solipsism (in which case I won’t even bother with you), there are objectively verifiable and falsifiable tests. To paraphrase Richard Dawkins, aeroplanes built to scientific specifications fly, while (cargo-cult) aeroplanes built to religious specifications do not. Differentiating between flying and not flying is not subject to cultural bias, and nor are other good scientific facts—and the hard sciences abound with them. (Our differences in opinion may have been conflated artificially due to my background in the natural science and this conversation partner’s background in humanities and softer sciences—the observer’s bias is much more likely to influence observations of people’s behaviour than observations of the behaviour of atoms, I should think.)

And let’s face it—ultimately, you have to reduce reality to a set of objective truths unless you want to descend into solipsism. What I wish I had said (but thought of too late) might be something like this: Intuition cannot be trusted because it cannot be tested. You have a feeling that something is true; well, I have a feeling that it isn’t. Only objective testing can settle it; otherwise there are no facts, but only opinions. I might also point out that I have a feeling that your idea that intuition is as good as science is dead wrong…

This, then, is what I think: Any scientific fact I hold up may be wrong (though some are fantastically unlikely to be so). Every scientist who ever lived, and every scientist who will ever live, is and will be fallible. But the scientific method is the only viable way of ascertaining truth beyond personal experience, and personal experience can be notoriously misleading; and any valid criticism of the scientific method as currently practiced will never tear it down, but only—at most—show how our current practice can improve.

I am open to challenges on this point.

I also feel—and this may well be controversial—that any field of inquiry that is irrevocably biased by cultural norms, etc., is not strictly scientific at all: I will not call it pseudo-science, but perhaps almost-science (or soft science…). This is not to take anything away from its practitioners: Strict science is ultimately the most accurate method for finding truth, but it is not therefore always the most practical (c.f. the old hypothetical example of the folly of having children empirically test their parents’ claims that the river teems with crocodiles). If your model purports anything beyond strict physical measurements, it has strayed from the field of hard science where this sort of reliability is possible.

Originally a post on ADD/ADHD in a forum thread elsewhere, I ended up getting sufficiently carried away in responding that I feel it’s worth reposting here.

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As with many other disorders, particularly psychiatric disorders, I think a major problem is poor or lazy diagnosis, which may stem from any of a number of reasons.

I’ve had a diagnosis of IBS for the past several years, which had me resigned to a chronic problem and perhaps taking meds to ameliorate (not eliminate, let alone cure) the symptoms—because the first doctor I spoke to listened to my description of the symptoms and prescribed a drug on the Take this, see if it helps principle. Fair enough, it helped—only a few years later a better doctor (at a walk-in clinic!) listened to the same list of symptoms and decided to run a simple test. This resulted in the lab-confirmed diagnosis of a bacterial infection that took two 10-day rounds of antibiotics at a total cost to me of $20 to clear up. Thus the first doctor’s laziness or negligence in not ordering a simple test cost me several years of pain (and several hundred dollars in medication).

Psychiatric disorders frequently suffer from vague or non-existent diagnostic criteria, especially when it comes to prescribing medication. It’s rather like zoological classification before the discovery of DNA: Disorders are classified according to similar symptoms (visible criteria) rather than analysis of underlying causes. Whales used to be classified as fish, even though they’re most closely related to hippopotamuses; elephants are more closely related to rock hyraxes than to hippopotamuses or rhinoceroses, but you wouldn't know it to look at them. Medical diagnostic criteria, when diagnoses are made without lab tests, are similar. Prescriptions of antidepressants are made without actually looking at patients’ brain activity of neurochemistry; I myself take Cipralex/Escitalopram (originally Celexa/Citalopram)—the criterion? I was clearly depressed, so they started me on the drug with the least potential for side effects. I was lucky; it worked out great. It’s still a crappy criterion, and lots of people get burned. (I know some people severely disillusioned by antidepressants, and others for whom they work great, but whose lives were made severly more miserable during a period of months or years of experimenting to find the proper treatment.)

AD[H]D sounds like a disorder with very much the same problem, only moreso. It’s clearly a spectrum disorder, or a set of spectrum disorders, with enormous potential for diagnostic confusion. I do not doubt that there are real disorders there, nor that medication can help sufferers, nor that it is a very good thing that such medication exists and is available to them. But I think it is terrible that so much work goes into developing these medications with no work done or publicised in properly analysing and targeting treatments to people who really do need them. And either this is at least theoretically possible, or the entire model is wrong to begin with—after all, it is hypothesised (or theorised, or known; I’m no expert) that neurochemical imbalances are at fault; then we should be able to test for them.

In more crass terms, I wish the pharmaceutical business model would shift to make, proportionally, a little more money in precise diagnostics and lab tests (test kits cost money, too!) and a little less (again, proportionally) on treatments.

I also wish that doctors had stiffer backbones and simply said no to parents or patients demanding drugs for which there is clearly no good indication. This is surely a major problem with AD[H]D; it's also a problem with drugs like antibiotics, often prescribed for viral conditions where they are of no use whatsoever (save placebo; and it's better to prescribe inert placebo or vitamins) but select for resistant bacteria.

There is no terribly novel material here; chiefly I write this little essay in order to have a fixed location to refer back to when, in the course of some argument on other over on Bullshido.net, I have to reiterate what I have said before (considering the length of this, I think excerpts will be called for). (It should also be mentioned that much of my thinking on the subject has been very directly inspired by posters on that website.) That said, on to the meat.

( A lengthy article… )

Prelude (this post isn't really about parrots): Because I like parrots, because I like to be prepared, because I am fond of knowledge, and because it is a way of living vicariously through strangers, I frequent a couple of webforums dedicated to discussing said birds. Because I am who I am, what I am, and the way I am, it's probably fair to say that a few of the discussions I enter end up less ‘discussions’ than ‘debates’. It's not just me, though—there are some definite hot-button issues, and one of them is crossbreeding different species (hybreeding as some people call it, probably more due to poor spelling than clever coining of terminology).

Think what you will of the pros and cons (or harbour no opinions at all), my basic stance is that (ignoring conservationist issues for the moment) the important consideration is whether it is cruel or kind to the animals. After all, if you breed pets, just as if you own pets, you owe it to the animals to make their captive existence a good one, and breeding unhealthy animals merely to satisfy human aesthetics reeks of unnecessary suffering to me—Persian cats, deaf Dalmatians, many dogs prone to hip dysplasia, whatever kills English Budgies younger than the wild genotype…the list could be made quite lengthy (but mindful of you, o humble reader, I shan't make it so).

Imagine my horror, then, upon encountering this ill-conceived sentiment:

All I can say is that God made humans and the animals. God is THE top engineer. If he didnt want it to mix he makes it genetically impossible (ie: humans and animals) He also made Man the keeper and caretaker of all the animals. ALL of them, he gave us brains to think, study and create.

Ignore the spelling and grammar for now. Ignore also the religious sentiments, because for the purposes of this discussion (and of that discussion), it doesn't matter whether life evolved naturally or under the guidance of some magical entity that wanted it this way. The simple and obvious fact of the matter is that either way, life is full of very nasty things, from anthrax spores to intestinal parasites, birth defects and cancer; the naturalistic fallacy gains nothing from being dressed up in holy robes. Of course, I spelled this out—and of course, the poster in question seems quite immune to reason, but I chiefly wrote it in the hope that someone less committed to fallacy will be swayed by it.

What I didn't say over there, because it would be a little too inflammatory and distract from the real subject (what was important there), is what disturbed me most about the cited sentiment: It is a total abdication of moral responsibility. The individual I quoted breeds animals, and takes the moral position that it is physically impossible for her to do wrong in so doing—the corollary is presumably that she therefore doesn't need to think about whether it's good or bad, because—it's impossible for it to be bad. (If you sense a minute earthquake just as you read these words, I suppose I am wrong and there is an afterlife—that'll be Ayn Rand, spinning in her grave.)

This crystallises exactly what I despise about even the non-violent manifestations of dogmatic religion. God wills it—case closed. No need for such a believer to exercise judgement, no need to carefully consider your actions, no need to analyse your own behaviour and check your motivations—most of all, no need to check whether your motivations ultimately result in harmful consequences! After all, God makes it impossible to do wrong.

It is entirely likely that this person will never cause any greater evil as a consequence of this version of faith than cross-breeding two birds of too-far diverged genomes and create a generation or two of genetically unfortunate animals; it's quite likely that even this won't happen (this is a breeder of birds but not necessarily a breeder of hybrids, and hybridisation isn't necessarily a bad thing). But consider the morality of a person like this! Couple it with the very best intentions and the very greatest kindness, and such a person may well commit atrocities, because if you hold a deeply-felt belief that it is just not necessary to consider the consequences of your actions, you have no idea what evils you may do. You have blind-folded yourself to them.

In that famous paraphrasing of Voltaire,

Those who can make you believe absurdities, can make you commit atrocities.

I'm think of myself as a rationalist, I might say. To the best of my ability, I use reason to deduce what the world is like, and I do my utmost to avoid basing any beliefs on the irrational.

But, you might say, and already I am taking a deep breath, But surely you aren't always rational! So many thoughts and feelings and emotions and opinions…there's no rational justification for why you think a flower is pretty or a kitten is cute¹; even you, o staunch self-declared Champion of Reason!—Are not even you irrational in your beliefs about subjective things?

At this point I might take a step back and slowly count to ten, but that's my problem; some things just annoy me very easily. Now that we're all calm, let's have another look at the above argument—probably not so very different from something you have heard, or perhaps even said?—and tear it to shreds.

It's really very easy and won't take a lot of time or space. There is no such thing as a subjective belief, or an irrational opinion, or for that matter an objective opinion or subjective fact. Beliefs and opinions are positions, but they are positions on different issues: A belief is a position on an objective issue, where there is a right and wrong answer, and where facts and evidence can be used and stringed together by rational arguments. An opinion, meanwhile, is a position on a subjective issue, which is by definition an issue on which there is not a right and wrong position. (Read this if you disagree.) Anyone but a small child realises that if I say It's a fact that kittens are cute it's a nonsensical statement (though see below); it is my opinion that kittens are cute. If I opine that (say) kittens are cuter than puppies, while you think that puppies are cuter than kittens, there's no such thing as right or wrong. We may reasonably agree to disagree, or unreasonably refuse to, but there's no such thing as proving the other wrong.

Of course, it remains true that opinions may be based on facts (more precisely, beliefs about what the facts are). If your opinion that puppies are not cute is based on having only ever seen the puppies of the Hairless Chinese Crested dog, then some new facts may cause you to re-evaluate your position on subjective matters. Or it may not. Perhaps you just don't find puppies cute. The point is, beliefs and opinions are intertwined, but there is a fundamental difference, and it is good to be aware of it.

The answer to the hypothetical (but, alas, not very hypothetical) argument at the beginning of this little essay, then, is this: I strive to be rational rather than irrational in matters of fact and belief; in matters of the purely subjective, rationality and irrationality have no meaning; these are un-rational things, orthogonal to logic, and insofar as your question makes any sense at all, the answer is no: I am not irrational when I take up arbitrary positions on subjective issues, because there is no rationality to defy.

Now you may protest that I'm only arguing semantics, so I'll dissect two pet peeves for the price of one and point out that semantics refer to the meaning of the elements of language (words, sentences, etc.), and to the study thereof, and if you really mean to protest that You're only arguing about the meaning of what I said!—then, well, yes, and I don't really know how to tackle your argument without considering its meaning through the semantics of its presentation.

¹ Actually, I gather there's a sound evolutionary reason for why we find puppies and kittens cute: They share those infantile traits which we have evolved to find adorable in order to trigger our nurturing instincts: Proportionally large heads, small snouts or noses, large eyes, and so on. These features are common to many (most? all? placental?) mammals and so probably go back a long way in our evolutionary history. I'm sure you still get my point, though.

Written about a month ago when I got involved in a debate forum, which I subsequently abandoned because it inspired me to write this.

One of the psychological phenomena most puzzling to me is the one called faith. I do not mean in the secular sense in which the word is sometimes employed (I have faith in your ability to do this), but the religious sense, which I define as belief without evidence. It may be that some theist reading this takes offence at that statement, but I have never once seen the word employed in a context where evidence is available. Rather, You must have faith! is a statement frequently used or resorted to when no evidence exists (or when purported evidence is overthrown).

Let me reiterate this, because it's important and easily leads to a debate about semantics—well, semantics (the meaning of words) do matter, so let's nail them down for the purpose of this debate! If you tell me (actual example of what I've been told) You have faith that the building you are in will not collapse, I will assert that it is not the same thing. This is faith based on reason and experience. There are thousands of similar buildings around that do not spontaneously collapse, and there is no reason to believe that this one differs in a crucial way from those. It has stood for a long time and shows no sign of structural damage. Architects have staked their reputations and livelihood on the safety margins, and engineers and construction workers staked their lives in working on it. In other words, there is plenty of evidence that the building won't collapse. You can call this faith if you like; I call it reasonable belief and use the word faith to refer to belief not based on such tangible evidence. Like this definition or not, please keep it in mind as you read on.

So what's this religious faith about, then? It seems to be about believing what you have been told without being given any specific reason to believe that it is true. It may take the form of believing everything you are told by your pastor, rabbi, yogic guru, or imam. It may consist in considering the Bible, the Qur'an, the Veda scrolls, or the Elder Edda inerrant. Strangely, it may sometimes consist in taking one of these scriptures—the Bible, say—and believing some of the things it says based on no other evidence, whilst discarding other bits (generally ones that offend the believer's moral sensibilities). It seems to me that this is based on an a priori assumption that the scripture as a whole is true, and each statement should be held true unless proven false; whereas a rationalist world view (one to which I adhere) demands that we consider every claim suspect unless some evidence can be shown to support it.

Sometimes excuses are offered up to this; the most recent, the lamest, and the most amusing that I have heard to date it this, to paraphrase: The Bible contains scientific accuracies. It's hard to believe that's not a joke, is it not? Pretty much every book in existence makes some mention of things that are scientifically verifiable—the Bible, the Qur'an, the Illuminatus! trilogy, and even, I expect Mein Kampf; this in no way lends credibility to their general contents. I could take any load of nonsense and insert some facts.

But most of the time it seems to come down to…well, to nothing at all, really; just blind faith without any kind of rational, evidentiary, or logical support.

And people use the word faith as though it had positive connotations!

There is another word that describes the same phenomenon, and one which, although its meaning (within the context being discussed) appears closely related to faith, has very different connotations; that word is credulity—though in a very contextual form. I'm sure that many readers (or at least `many' relative to the total size of my readership…) will consider this an offensive statement when applied to religion. Oddly, the same is probably not true with respect to any other topic. Consider a text that is some two thousand years old, and consider a person who, although he has no corroborating evidence for its claims, believes whole-heartedly in it and will allow nothing to change his mind. If it is a text on astronomy, or anatomy, or physics (on an earthly scale), I am sure we will all agree that he is just plain wrong-headed. If it is a text on religion—on the origins of life—on the nature of the universe on a grander scale—why, then, nothing could be more sound than believing; it is not credulity, but faith!

(Since I first wrote this little essay, this comic went up, rather neatly accentuating the above.)

What really puzzles me is that some people go on to describe this as a virtue. Some people would have us believe that it is better to go on blind faith than to use reason and critical thinking. I can see why they should like people to do so—but what benefit can this possibly have for the followers of the creed?—it is all too obvious how it benefits the leaders.

I'm pretty familiar with depression. I have experience of it both first-hand, second-hand, and third-hand (i.e. as a sufferer, as someone who knows sufferers, and as someone who has heard and read about sufferers). Depression launches a many-pronged assault on those who suffer from it; it is a subtle and complex thing. One of the more devious and peculiar ways in which this manifests is in the way it causes guilt in its sufferers.

There are some people, I'm told, who upon hearing that someone is depressed will tell the depressive It's all in your head; just shake it off, or something to that effect. This is, by and large, callous (if spoken out of anything but ignorance) and totally ineffective, except insofar as to effect guilt. I've never been told this, personally, but I didn't need to—I came up with the accusation all by myself. In fact, in my experience, most depressives seem to feel this. (It's not a large sample, admittedly, but 100% of a small sample may still be taken to indicate something…)

This often takes the form—often explicitly—of a feeling that Other people have it so much worse than me, yet I can't even cope with this. I don't know how often I've said it. I've lost count of the times I've heard it. Why, I would ask myself, am I such a whiner—incapable of coping with this little depression, when X dealt with an alcoholic father, Y has an emotionally abusive stepfather, and Z has dealt with so many crises—yet they have all come through strong where I am weak?

And it's really kind of strange. If I catch a cold—and I'm just getting over quite a bad one—I don't feel guilty about it. Why should I? I contracted a virus that my immune system was incapable of dealing with quickly and effectively enough, so I got sick. Theoretically I could perhaps have prevented it, by eating more vitamins, getting more sleep, washing my hands more often, or some other means—but oh well, I didn't; I got sick and now I'm better and that's the end of the story. I also don't feel shame that my immune system is (arguably) weaker than that of someone who was exposed to the same pathogens and didn't end up sick.

With a mental illness—such as depression—it's not like this at all.

Because it's a disorder of the mind, there is this notion that one should just shrug it off—Just get over it! But it doesn't work like that, as any sufferer of depression can tell you. My mind can no more shrug off depression than my body can shrug off a viral infection; much less easily, in fact, because by and large my immune system does a good job of keeping me on my feet. Why is this? Why is it that if I am brought low by a viral or bacterial infection, by fractures, contusions, concussions, or lacerations, by food poisoning or a chemical imbalance in my blood like high cholesterol or low blood sugar, that's acceptable (in a moral sense)—but if I have a chemical imbalance in my brain, I'm supposed to just shrug it off? Or—if my mental disorder is more complicated or less easily pinpointed than that—if my thoughts are just twisted into a Gordian knot, why is it that my mind is assumed to be a cutting blade?

I don't know the answer to these questions—the only real answer I have is If you talk like that to depressives, kindly do us all a favour and shut up because the tough love method only goes so far and only with certain people, and depressives as a rule have low enough self esteem as it is without being told they're lazy for not magically fixing themselves. But I do wonder, and it occurred to me that this might be related to a very peculiar division.

Did you notice that I made a very clear distinction in the earlier parts of this little essay between physical disorders and mental ones? Very possibly not—we're used to making that distinction—but I did, very deliberately, although I cringed every time I did it. Because, really, that distinction is largely nonsensical. It is, I believe, chiefly based on a lack of understanding—a primitive time when the physical nature of thoughts and emotions was entirely mysterious (as opposed to now, when it's only mostly mysterious…) and, critically, not understood to be a physical process. Understanding of anatomy was virtually non-existent (consider the ancient peoples who thought that the heart or stomach was the seat of consciousness!) and belief in spirits was rampant. These days it is intellectually evident not only that the brain is the physical seat of consciousness, but also that the mind itself is an emergent effect of very physical processes: Chemical, electrical, and so forth.

The consequences of this are, of course, complex and manifold, but primarily it creates a kind of disconnect in the way we regard ourselves. Nobody frowns at an expression like body and mind, as though they were separate things! We would not speak thus of body and liver, body and spleen, or body and large intestine. It also leaves room for concepts along the lines of mind over matter, which implies that mind is not of matter. Without this illusion or delusion, there'd be little room for ideas such as physical disorders being qualitatively different from mental disorders; they are all physical disorders, albeit some more intimately involved with the mens (or mentis: Latin for mind, hence mental et al.). I think it is detrimental in a much more general sense; it opens the way for so many mistakes of thinking: The body being subordinate to the mind, the mind's reactions to physical stimuli being shameful, and so on. In the context of the original topic, however, it is this: Depressives are often fooled, or fool themselves, into thinking that a mental disorder is non-physical; that the mind is non-physical; and that the metaphysical mind should therefore control the disorder.

In my own battle against depression, one of the largest milestones was overcoming this sense of shame. Ironically, what saved me was a massive tragedy. In 2004, my father died, suddenly and unexpectedly, of an aneurysm. Shortly thereafter, my younger brother, unable to cope with this on top of his own, previous problems, committed suicide. My family was of course plunged into a state of shock and grief—call it a form of depression. This is expected, and obviously nobody can blame anyone for feeling terrible after having lost two members of their family. In other words, I ended up in a state of deep and justified depression—a depression for which I felt no guilt.

I felt slightly worse than I had before.

This taught me a great deal. I realised that I had gone from deeply depressed to slightly more deeply depressed—but I had already been so low that the change was not really drastic. I also realised that People who have it so much worse cope better was preposterous, because I had already had it quite badly. It was not a set of external circumstances—like poverty or abuse—but circumstances of brain chemistry and so forth, but I had already had it badly, all the same. Suddenly people started telling me how impressed they were that I held together—how strong I must be—when I had said the same to others for years, and imagined myself so very weak! The disparity in strength was an illusion. Those people you may be looking at and admiring for their strength under pressure greater than that you suffer—they're just doing their best to hang on, just like you; you may one day find, as I did, that there's a low point where you keep going not because you are strong but because there is nothing else to do.

Or you may be overwhelmed by tragedy or bad brain chemistry or bad wiring in the head, and there's nothing more intrinsically shameful about this than passing out when you get up too fast or suffering from diabetes.

In writing this, I feel like I have expressed myself poorly, either because I wrote less well than usual or because the material demands higher standards. Whichever may be the case, I apologise, and I hope to revisit this at some point, rearrange it, and sum it up properly in closing. For now, I leave you with these thoughts in the hope that their relative rawness will encourage you to develop them further where I have failed to do so for you.

I hope, above all, that this does not leave you feeling pity for me or unequal to my strength—if you feel either, please re-read it, and read it more carefully this time! I write about my own experiences not to boast my strength, but to illustrate how this perception of strength is usually an illusion; not to show what awful circumstances I found myself in, but that depression is depression no matter the external circumstances and deserves to be taken seriously whether something obviously awful happened or not. I don't want pity for anyone, only understanding—and that being said, I'm happy to say that I've come a long way since 2004. These are things this essay was not meant to effect.

What I do hope—the ultimate (pipe?) dream in writing this essay—is that someone will read it who does feel this irrational guilt, weigh my words carefully, and find that his or her guilt is unnecessary—the condition is no one's fault—and the weight on guilt be lifted off shoulders that already bear a very real and legitimate burden.

I recently had an email exchange with someone (on a pretty good and amicable level, fear not) on the topic of religion. One thing that came up was the common Christian theme of free will, which supposedly justifies Hell. Humans, the argument goes, enjoy the privelege of free will. We may freely choose to believe in God and go to heaven and enjoy eternal bliss; or we may freely choose to reject God, in which case we will go to Hell. (I disagree that belief is a simple matter of choice, but this is tangential to the topic du jour.) I responded to this with an analogy:

Suppose I am the supreme ruler of a kingdom. I make a royal decree: You may wear any colour of clothing you want. You have a totally free choice in the matter. Your will is unbonded by mine. The only catch is that if I catch you wearing anything but green, I'll throw you in the dungeon, pull out your nails with pincers, and crush all the bones in your hands and feet. Still, you're free to choose that.

The analogy should be pretty obvious. The law of the land does not, in effect, say that you are free to choose what clothes to wear. Rather the law (whether we call it such or not!) demands that you wear green, and enforces it with a grisly punishment. If I tell people you're free to choose, that is merely a cruel mockery. Free will is not applicable under coercion.

The chief differences between my analogy and the biblical version is that the crime being considered is of a much more totalitarian nature in the Bible: Not a matter of doing, but a thought crime—I am, in this view, to be punished for the crime of not believing in a story that reason and evidence do not (in my view) support; and that the punishment is much worse—my hypothetical king merely tortured you for a little bit, while the Christian Hell is eternal torment! (Mark 9:43, Luke 16:19–28, …)

As an aside, I think that this issue is morally important. I consider any mainstream Christian who believes that I will go to Hell for my views malicious. I am of course personally quite untroubled by thoughts of Hell, being very skeptical indeed of its existence. However, if a person believes that I: God exists; II: God is all-powerful; III: God is perfectly just; IV: I will go to Hell for my unbelief, then I think that said person bears me malice. The reason is simple: If you believe that God will send me to Hell for my unbelief (IV), and God is all-powerful (II), then clearly (you believe) he has a choice in the matter and chooses to subject me to eternal torment. (I do not believe in any gods at all, but I assure you I would not make the choice of eternal torment, so this is not a simple free will issue.) As per (III), his decision was, in your opinion, a just and fair one. Ergo, you think it is fair that I should suffer eternal torment for not believing.

I've actually had someone tell me that they hold all of the aforementioned beliefs, and this person had the gall to take offence at my reacting unfavourably.

Originally posted as a comment to my friend Scott's blog, over here, but I think it stands well enough alone for me to post it here:

I think one of the major problems in all intellectual discourse (or lack-of-intellect-ual discourse) is that critical thinking is a skill not sufficiently well taught. At the risk of sounding arrogant, I tend to think of myself as a reasonably intelligent person; further braving the danger of the impression of nationalistic pride, I think that I have come through a respectable educational path: Swedish elementary and secondary schools, Canadian universities. Even so, and even given a natural tendency toward skepticism and a love of learning, I didn't learn to critically disseminate sources until rather recently; presumably it was gradual over the course of many years, but it reached a culmination (relative, of course, to whatever my present understanding may be considered to be) less than two years ago when I started to read research papers and came to realise that even at the cutting edge of scientific endeavours, there are opinions and errors and uncertainty, and even in very well-written papers by very intelligent and educated people, even in papers with terrific and accurate ideas, there may be errors. (Reading Darwin's The Origin of Species was perhaps a more obvious lesson in the same, although more recent.)

So where am I going with this? Well: Even with the resources available to me, I was still left with some nasty residual notion that purported factual writings fell into the two categories of true and not true. This is, alas, a dogmatic view—one with room to eliminate dogma I could identify as false, happily, but dogmatic nonetheless. Here we go back to Arrogance Land: I suspect that if I was left with so faulty a perception for so long, then a great many people—certainly not all! But a significant chunk of the population, whether large minority or majority great or small—are probably likewise impaired. Evidence certainly seems to back up my arrogance, here.

Now, I think it is essential for a rational view of the world to accept or reject every purported fact provisionally, and to keep in mind that even well-established facts like the theories of gravity, electromagnetism, and evolution have a probability of (very very slightly) less than 1, and even way-out-there conjectures like (equivalently) Christian theism, voodoo, and Russellian teapotism (with apologies to the late, great Russell for coining such a term) a probability (very slightly indeed!) higher than 0. P = 1 is dogmatic acceptance. P = 0 is dogmatic rejection. 0 < P < 1 is acceptable territory for rational thought. (Of course, we may often have ε ≈ 10^-x for quite a large x…)

As I'm writing that, it seems to me that a reasonable hypothetical model for Truth would be a Bayesian network of facts…

It occurs to me that science, as a whole, is a process of memetic evolution. We could even borrow terminology from biological evolution: There are mutations and crossovers; the fittest survive—those most able to stand up to critical scrutiny … I think perhaps the largest difference is that while abiogenesis must be regarded as an uncommon event in nature (or at least, it is reasonable to assume that organic material that is now produced through some form of abiogenesis is consumed by extant, more advanced life forms), memetic abiogenesis—“anepistegenesis”?—is comparatively common. (Of course I do not mean that these ideas are spontaneous; they are properly derived from observation, but they have no memetic ancestors.)

Edit: It seems that Dr. Dawkins's adjective is memic, not memetic. Mea culpa.