Petter's blog

From this story, Strong Passwords Not As Good As You Think, by some commenter called Rob the Bold:

According to the article (cited by the citation):"Users are frequently reminded of the risks: the popular press often reports on the dangers of ïnancial fraud and identity theft, and most ïnancial institutions have security sections on their web-sites which oïer advice on detecting fraud and good password practices. As to password practices traditionally users have been advised to . . . "

-Choose strong passwords

-Change their passwords frequently

-Never write their passwords down

I would suggest that this is a case for the popular quip: "Pick two".

Personally, I can’t be arsed to change passwords frequently, which makes unique passwords all the more important: Since I rarely change them, I need to make sure that if somebody steals all the passwords from site A, that doesn’t compromise my accounts on sites B through Z. Have I plugged SuperGenPass lately?

A faithful remake of The Secret of Monkey Island—and by “faithful”, I mean…it comes with a toggle so that you can seamlessly switch between the 3D-rendered-with-hand-drawn-backgrounds version and the original.

I have wished for the past fifteen years or so that some company, somewhere, would take an interest in reviving old games. Recently, this has become a reality: Good Old Games and Steam both offer classics powered by (OSS) software like ScummVM and DOSBox, and remakes like this. It makes me a happy gamer, and I gladly open my wallet for stuff like this (ironically, paying for games that I only had access to pirated copies of as a child).

No atheist should call himself or herself one… A more appropriate term is “naturalist”, denoting one who takes it that the universe is a natural realm, governed by nature’s laws. This properly implies that there is nothing supernatural in the universe. […] People with theistic beliefs should be called supernaturalists, and it can be left to them to attempt to refute the findings of physics, chemistry and the biological sciences in an effort to justify their alternative claim that the universe was created, and is run, by supernatural beings.

A.C. Grayling, Against All Gods

I am currently reading a collection of essays on philosophy and logic that suffers severely from not using symbolic notation—some of the subject matter is heavy, some less so; some uses lingo that I’m not familiar with—but it is needlessly and greatly complicated by couching logical relationships in English. For instance, I was initially rather confused by the syllogism,

If if p then q then if if q then r then if p then r

This, as I said, rather confused me, until I realised (by visualising the symbolic representation!) that all it says is that

(p→q) → ((q→r) → (p→r))

which is a lot clearer, but also happens to be equivalent to

((p→q) ∧ (q→r)) → (p→r)

which is obviously¹ true. Of course, I should have realised this from the outset because it is and is clearly said to be a straightforward syllogism, but that’s a matter of terminology rather than logic, and my terminology is, I admit, pretty shaky. However, I hope that you can sympathise with me when I say that I find the initial wording of the syllogism pretty unwieldy: If if p then q then if if q then r then if p then r…

If you think that it’s not so bad, and English really should suffice to clearly express these concepts, then try to wrap your head around this, quoted from a footnote:

If if if if q then r then if p then r then s then if if p then q then s

I don’t yet know what this means because I haven’t had the chance to reformulate it, mentally or on paper, in symbols.

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¹ Well, “obviously” only if you know the notation, but it’s fairly simple:

• x → y means “if x then y”, usually read “x implies y”.
• ∧ means “and”: “x ∧ y” reads “x and y”, and is true if, and only if, both x and y are true.

(In case of embedding problems, click here.)

The other day, I picked up Why Evolution Is True by Dr. Jerry Coyne from the library. A few days later I had finished it, and a few days after that, I want to write a few lines on what I think about it.

The book’s aim—as very straightforwardly implied by the title—is to lay out in concise form a reasonably comprehensive (and comprehensible) body of evidence for evolution. As such, it spans a pretty wide range of areas—biogeography, palæontology, genetics, and so forth. At only ~300 pages, it has to go at a pretty good pace, and it does—but it’s largely a good thing. The book is accessible, but not dumbed down; it is brief and concise, but not superficial. It lays out a huge breadth of evidence with plentiful references (many internet references) for those who want more depth.

My brief opinion is: This is one of the best, and possibly the best book I have read in terms of laying out precisely what the title claims: Why Evolution Is True.

The funny thing is, when I put it down, my mind was actually full of gripes. I was constantly wondering about the tone—it wasn’t very technical, but couldn’t it have been simplified in places? I now think that, yes, it could have, but I don’t think it would have been to its advantage. It’s simple enough to be accessible to laymen, and that is enough. Let’s not pretend that it isn’t science, don’t give the impression of condescending, and don’t sacrifice precision by avoiding scientific terminology altogether.

I also found one argument missing that I might have liked to see—one that Richard Dawkins has made wonderfully lucid in more than one book—that of the difference between “single-step” and cumulative selection: The counter to the old “747 in a junkyard” argument¹. In fact, its omission irked me very greatly because I think it is such an excellent counter to fairly common creationist/cdesign proponentsist objections to evolution by natural selection as being statistically impossible.

However, I think that the reason why this irked me so very greatly may be because virtually every other persuasive argument is either explained or alluded to; and the focus of the book is, after all, on evidence rather than argument. If someone near you suffers under the delusion that evolution is not a fact, and the neo-Darwinian synthesis is not a very solid scientific theory, you could scarcely do better than to recommend this book to them—perhaps with an explanation of cumulative selection to solidify the deal; or have them graduate to Dawkins, e.g. The Blind Watchmaker, which takes a complementary approach of theoretical argument (though on a very accessible level!) as contrasted to Coyne’s straightforward presentation of evidence.

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¹ The “747 in a junkyard” argument stems from this quote by astronomer Fred Hoyle:

A junkyard contains all the bits and pieces of a Boeing 747, dismembered and in disarray. A whirlwind happens to blow through the yard. What is the chance that after its passage a fully assembled 747, ready to fly, will be found standing there? So small as to be negligible, even if a tornado were to blow through enough junkyards to fill the whole Universe.

Hoyle was not a creationist—but never mind his motivation. Creationists have hijacked this quote and use it to point out a perceived implausibility of evolution. The chance of something so complex as an eye, for instance, arising by chance, is of course minuscule. How can “Darwinists” claim that it arose purely by chance? The answer is, of course, that they don’t, because nobody thinks that the eye sprung forth fully formed from a single mutation, but rather incrementally, and if it was improbable, it was a matter of cumulative selection.

What do I mean by “cumulative probability”? I mean that we can build up on past successes. Take, for example, a coin flip. The odds of getting heads on a single flip is ½. The odds of two flips simultaneously resulting in heads are ½×½ = (½)² = ¼. Three heads at once? ½×½×½ = (½)³ = ⅛. —And so on. The odds of, say, 100 heads all at once are 1 in 2¹⁰⁰: Less than one in a thousand billion billion billion. If we flip our 100 coins once a second, it will take us on the order of a million billion billion years to flip all 100 heads at the same time. That’s about 100,000 billion times the age of the universe. This is single-step selection: We’re looking for a specific result, and we need to get it in a single step: The simultaneous flip of 100 coins.

But natural selection doesn’t require this. The theory of evolution by natural selection predicts that any helpful change will be “saved up” and passed down to further generations—it doesn’t have to be perfect—it just has to be an improvement, however small. If we flip 100 coins, we’ll almost certainly get some heads—the odds of getting 0 are the same as getting 100, and that will virtually never happen. We’ll probably get about 50 heads. Now we’re allowed to save them, and only have to re-flip the 50 tails. Probably about half of them will be heads. —And so forth. If we assume that we get half heads, half tails every time, we’ll have 100 heads—on average—after 7 flips or so.

You will note that 7 is rather less than a thousand billion billion billion. We can now accomplish the task of flipping 100 heads in about 7 seconds rather than 100,000 billion times the age of the universe (if we can sort through them quickly enough…). The argument is vastly simplified, and obviously none of this applies at all closely to biology.

What should be clear—and the point of the argument—is that there is a huge (in fact, a geometrical) difference between single-step and cumulative selection.

A wingnut called Terry Eagleton wrote a famously bad review of Richard Dawkin’s The God Delusion.

Dawkins on God is rather like those right-wing Cambridge dons who filed eagerly into the Senate House some years ago to non-placet Jacques Derrida for an honorary degree. Very few of them, one suspects, had read more than a few pages of his work, and even that judgment might be excessively charitable. Yet they would doubtless have been horrified to receive an essay on Hume from a student who had not read his Treatise of Human Nature. There are always topics on which otherwise scrupulous minds will cave in with scarcely a struggle to the grossest prejudice. For a lot of academic psychologists, it is Jacques Lacan; for Oxbridge philosophers it is Heidegger; for former citizens of the Soviet bloc it is the writings of Marx; for militant rationalists it is religion.

What, one wonders, are Dawkins’s views on the epistemological differences between Aquinas and Duns Scotus? Has he read Eriugena on subjectivity, Rahner on grace or Moltmann on hope? Has he even heard of them? Or does he imagine like a bumptious young barrister that you can defeat the opposition while being complacently ignorant of its toughest case? Dawkins, it appears, has sometimes been told by theologians that he sets up straw men only to bowl them over, a charge he rebuts in this book; but if The God Delusion is anything to go by, they are absolutely right. As far as theology goes, Dawkins has an enormous amount in common with Ian Paisley and American TV evangelists. Both parties agree pretty much on what religion is; it’s just that Dawkins rejects it while Oral Roberts and his unctuous tribe grow fat on it.

Terry Eagleton, Lunging, Flailing, Mispunching

The most famous reply to this is P.Z. Myers’s satire, The Courtier’s Reply, which is one of his finer writings and vastly enjoyable. Today, though, I came across a succinct reply I had not seen before, by philosopher A.C. Grayling. It is perhaps less offensive in that it does not satirise, but it gives Eagleton about the same shrift:

Terry Eagleton charges Richard Dawkins with failing to read theology in formulating his objection to religious belief, and thereby misses the point that when one rejects the premises of a set of views, it is a waste of one’s time to address what is built on those premises (LRB, 19 October). For example, if one concludes on the basis of rational investigation that one’s character and fate are not determined by the arrangement of the planets, stars and galaxies that can be seen from Earth, then one does not waste time comparing classic tropical astrology with sidereal astrology, or either with the Sarjatak system, or any of the three with any other construction placed on the ancient ignorances of our forefathers about the real nature of the heavenly bodies. Religion is exactly the same thing: it is the pre-scientific, rudimentary metaphysics of our forefathers, which (mainly through the natural gullibility of proselytised children, and tragically for the world) survives into the age in which I can send this letter by electronic means.

Eagleton’s touching foray into theology shows, if proof were needed, that he is no philosopher: God does not have to exist, he informs us, to be the ‘condition of possibility’ for anything else to exist. There follow several paragraphs in the same fanciful and increasingly emetic vein, which indirectly explain why he once thought Derrida should have been awarded an honorary degree at Cambridge.

Anthony Grayling

Via Facebook’s internal notifications:

We have decided to focus on something more exciting. New Layout Vote\'s name and functionality will be changed next week to SpeedDate, a fun way to meet new people. Data entered into the original app won't be used anymore. Check it out, and if you want you can opt out here. 13 minutes ago

I can’t make up my mind on what this might be. Idiotic joke? Peculiar hack? Astonishingly moronic decision? The notion of transforming the poll that revealed that 94% of their user base were displeased with their redesign into a “SpeedDate” application is rather surreal.

Update: I was going to write another post lambasting Facebook for this, but I did my fact-checking and found that (contrary to my impression, and popular belief) the New Layout Vote was not developed by the Facebook team itself—it was a third-party app. It’s still sleazy and a cheap tactic to harvest—effectively—user accounts to spam, but anger should be directed at SpeedDate and whoever wrote the app, not the Facebook team.

Interesting and peculiar. It turns out that Tonya’s way of deleting entries is to just delete everything that is not resubmitted. This should work, but it fails on the last entry. The reason why it doesn’t work is a little bit subtle and weird.

The query in question is

db()->execPrintf('DELETE FROM am_releases_templates WHERE release_id = %i AND id NOT IN %@i', $release_id, array_keys($template_ids));

The question is, what happens when $template_ids is empty? What does printfQuery() do? printfQuery() is mine, of course, so I should know, and what I did was to pass in the tuple (NULL), since SQL considers NULL not equal to anything. So, I thought, for any value x, `x IN (NULL)` should be false—and consequently, `x NOT IN (NULL)` must be true. Stupidly, I didn’t test and verify this.

It turns out that MySQL returns an empty result set when you compare against the tuple (NULL). That is, `...AND id NOT IN (NULL)` is *not* the complement of `...AND id IN (NULL)`, so the union of `x and not x` is...an empty set, rather than all the elements. This is rather weird.

Conclusion: I really don’t like MySQL.

Update: Not just MySQL, but SQL in general, it seems.

By the way, you can find my key here. The key ID is AA544F6E. Feel free to contact me to verify.

Since I’m on a security spree, finally getting my arse in gear to do what I should have been doing for a long time, I decided to also generate a new PGP key that actually matches my current email address and perhaps (wonder of wonders) actually sign email by default. I may or may not bother about encryption; it’s certainly a nice-to-have, but I’m trying to ease into good habits, and I want to read up more on backing up public keys¹.

What this means is that I am curious about what mail client you use, because people reading this post comprise a pretty hefty chunk of all the people whom I want to be able to read my mail. Since some mail clients (notably Microsoft clients) are a bit iffy when it comes to features like PGP/MIME, from what I’m told, it would be very nice to know what I can rely on recipients being able to receive…

Poll #1420360
Open to: All, detailed results viewable to: All

What mail client do you use?

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…And by you I mean all of you, so please at least take the time to read and think about this. Don’t worry if there are a few technical bits thrown in here and there; the message should be quite clear.

I have been putting off securing my data for much longer than I really should have. I am not, by nature, a paranoid person, and when it comes to high-powered encryption solutions, I agree with Randall Munroe of xkcd. I don’t need 4096-bit encryption, I am not going to worry about forensic analysis…I do not live in Iran. Someone said, and I agree, that

Alltogether, encryption of /home and /tmp prevents someone to access your private data by just using a Live-CD with your computer.

I consider something secure, when the effort to bypass or break it exceeds the benefit you get from breaking it.

But I do care enough that I want my data encrypted, and you should too—especially if any of the following applies to you:

• You use a laptop. A user account password prevents somebody from just logging in as you, and is of course a must-have, but account passwords won’t help you at all if your laptop gets stolen, because all anyone needs to grab all your data is a rescue or install disk.
• You use your browser, mail client, etc., to save your typed-in passwords or logged-in sessions.
• You use only a small set of passwords, so that having one password compromised impacts you in many places. Actually, if you do, read this and start using SuperGenPass.

As it happens, all of the above apply to me, and I know the risks full well, so it’s hard to justify the fact that I have gone so long without encrypting my data. In all honesty, it’s sheer laziness. At least I am catching up now…

The biggest danger is that if you have a laptop and it gets stolen, somebody could use a combination of saved passwords and password reset mechanisms—after all, they have access to your email account!—to break into virtually any service you have electronic access to. This is not just about somebody reading your private letters (bad enough); this is about somebody able to use any electronic service you can use, possibly with the exception of your bank if their security model is good. Of course, this applies to desktop computers as well, in case of burglaries, but I consider the likelihood of a break-in to be much lower than the risk of somebody grabbing my laptop off a café table while I have my back turned, or somebody stealing my backpack, laptop and all.

I will reiterate something Jeff Atwood said, because it’s important:

1. Number one with a bullet: your email account is a de-facto master password for your online identity. Most -- if not all -- of your online accounts are secured through your email. Remember all those "forgot password" and "forgot account" links? Guess where they ultimately resolve to? If someone controls your email account, they have nearly unlimited access to every online identity you own across every website you visit.

2. If you're anything like me, your email is a treasure trove of highly sensitive financial and personal information. Consider all the email notifications you get in today's highly interconnected web world. It's like a one-stop-shop for comprehensive and systematic identity theft.

I’m not here to tell you how to encrypt your data, because I don’t know how to do it in Windows and I don’t know how to do it on a Mac. (I’m told, in the latter case, that it is easy.) I am here to tell you that you should encrypt your data! —And if you choose not to, be aware of the risks.

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One thing should be added: If you encrypt your data, backups are critical. Of course, backups are always important; I would hate to lose years of work, correspondence, important data, tax files, and so on, due to a hard drive failure—or, say, an apartment fire that destroys both my computers, which is quite bad enough without data loss on top of it.

But with encryption, it’s even more important. If a regular, unencrypted file system gets damaged (software error, crappy old hard drive, …), your OS can probably cope with this and recover pretty much everything you care about, because the on-disk format is well known and understood. Encryption throws a $5 wrench into the works here, by making the on-disk format extremely obscure: That’s the whole point, after all. This means that if your encrypted file system gets damaged, there’s a significantly higher risk that all your data become unreadable. (For example, if you use Linux/LUKS, like I do, and the metadata sectuin containing the master key gets damaged, the partition is lost.)

I didn’t think twice about this, because I have a reasonably solid backup strategy in place (everything I care enough about is synchronised with a remote server). If you want to encrypt your data but don’t have a backup solution in place, though, you should come up with one first.

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If you’re using Linux, you should set up encryption when you install it. (Well, you should do this regardless of your OS, but this is a Linux-centric section.) With Ubuntu, it seems extremely easy, but I wasn’t thinking about it when I got my new laptop (I was too excited about a new toy, and having a laptop I could actually use), so I had to convert to an encrypted system after the fact.

Most importantly, I am encrypting my /home partition, where all my data reside, using LUKS (referring to this guide). I consider this by far the most important part—it’s where all my data reside, all my cached passwords could be stolen, all my email is backed up. It was not at all difficult—the only problematic part is that I needed to move the data aside in order to encrypt the partition (I don’t know of a way to encrypt it in place). For this reason, I have yet to do this on my desktop computer: I have no partition large enough to hold all the data!

I also encrypted my /tmp and swap partitions, where temporary data are kept, because cached passwords, sessions, etc., could potentially be retrieved from thence (here, I used this guide). Because they are (or can be) cleared on reboot, I opted for the recommended solution of using /dev/urandom as the key file: The password is randomly generated on boot, different every time, and thus pretty damned secure. I am told I should also encrypt /var/tmp, which is a bit trickier, because I don’t want to have to type in two LUKS keywords on boot. How important is it to encrypt /var/tmp? I gather KDE caches data there, but I do not use KDE. I suppose I may generate a keyfile and store it on the encrypted /home partition, or hell, even symlink it to a /home/cryptovar directory—on rare occasions when /home is not available, I don’t imagine I’ll care much about missing /var/tmp! Thoughts?

A very interesting and somewhat disturbing article, here.

It would be disingenuous to imply that non-vaccination might not lead to an increased incidence in vaccine-preventable illness. It would be equally disingenuous to state that this possibility poses a great threat to America's children.

Dr. Jay Gordon, quoted at Respectful Insolence

It would be…disingenuous to state that this possibility poses a great threat to America’s children.

Never mind polio, which killed or crippled thousands of children every year before it was eradicated by vaccines, the fear of which ruled some people’s childhoods.

Never mind smallpox, an epidemic disease with an average fatality rate of 30%, also eradicated by vaccines.

Never mind Hemophilus influenza type b (HiB), a disease now nearly forgotten in pediatric wards thanks to vaccination, but which used to cause disease in one of every 200 children under the age of 5—whereof ½–⅔ developed meningitis, with a mortality rate of 5% and rate of permanent brain damage of 30%.

No—none of these, nor any of the other among the dozens of vaccine-preventable diseases now eradicated or dramatically reduced, pose a great threat; thus, because there’s no great threat, we should cautiously withhold vaccination just in case we ever find evidence that they cause any harm. We have no such evidence, but why jump the gun? It’s not like they prevent any great threat.

Between work, something of a social life, programming for fun, and exercise—currently jiu-jitsu twice a week and weightlifting once a week—I manage to keep pretty busy, with reading always available to fill out the corners. There are a great many things I would like to do, but just can’t prioritise (kickboxing—I could do it, but when I’m there I’d rather practice jiu-jitsu), or don’t have enough time to invest in (judo).

And yet there are a couple of things I would like to either try or actually pick up. For instance, I would like to learn to fire a gun. This has nothing to do with self defence or anything like that. I don’t want to own a gun, and I can’t imagine carrying a gun around even if I legally could. I’d just like to go to a range, rent a gun, and learn to shoot it, because it seems interesting.

Then there’s the Academie Duello, a school in downtown Vancouver—a five minute walk from my office!—that teaches swordplay. Not modern fencing with ultralight foils that don’t work as weapons, but mediæval and renaissance swordplay: Rapier, sidesword, longsword… (They also have other weapons—quarterstaff, spear, sword and shield, pole ax—and knightly pursuits like falconry seminars.) Since they offer a free introductory class, since they have lunch-hour classes, and since they are, as previously mentioned, a five-minute walk from my workplace, I think I may at least go try it out one of these weeks.

I wish a week were a lot longer, work a lot less time consuming, and my energy levels considerably higher…

Most of my life, I have not fit in very well in groups. It’s not necessarily a bad thing—sometimes it is and sometimes it isn’t. I’d rather not fit in that compromise on being myself, and no matter how many potential friendships and group memberships I might lose, well, there are more people out there and I would rather wait to gain the friendships that require me to sacrifice nothing. (This is not an excuse not to grow, or to retain poor social skills; “sacrificing” means “losing something that is not negative”.)

Sometimes it can be a bit of a bother, though. Today saw some event called “Car free day” on the Drive, and wandering up and down the Drive with Sarah I felt that familiar sense of “outside-ness”, as though there were an invisible glass wall around me and everything around me. Usually, as I say, this does not bother me, because I’m used to it, because there’s an awful lot of people whose society I care for and about not at all, and because I can do rather well on my own anyway, but the Drive is an area with so many colourful, liberal, and interesting people that I wish I could relate to them. In a way I love the Drive; in another way (but for much the same reason), it makes me sad; it’s a place where I do not want to feel like an outsider. With no piercings and no tattoos, I feel like I stick out visually like a sore thumb, and I do not know how to approach people…

The only context I have ever found to blend right in has been at various parties and gatherings that Erin has invited me to. It’s really kind of funny—I like Erin, I think she’s a great and nifty person, and I enjoy talking to her, but we aren’t close, and for all that we can usually find something interesting to talk about on those occasions when we do talk, we don’t talk often, and I can’t relate to some of her big passions (I can just about tell rhododendrons from rhubarbs; that’s as far as my gardening knowledge goes). Not to put too fine a point on it, I’m not a hippie… Somehow, though, the people she surrounds herself with all seem to share some quality that lets me join in and just fit in with the crowd, without feeling as though I am held (by myself or by others) at an invisible arm’s length…I can talk and laugh and not feel drained. Usually, socialisation in groups—even when I do enjoy it—takes a lot of emotional energy; these gatherings do not. I don’t know what the quality may be. I don’t know how to seek it out for myself, and I still don’t know how to approach, so I am beholden to someone to start conversation with, a seed crystal of socialisation. But once there it is effortless and remarkable.

I am often somewhat at a loss when people speak of building community or a sense of community—I feel rather vague on what the word even means, in much the same way as I am puzzled by the word spirituality. It’s the mental equivalent of being asked to flex a muscle you do not know how to control (unless you know how, go ahead and move your ears). Perhaps this is it—community. Perhaps I should try to seek out more of it, somehow.

Over the course of many a fruitless religious debate, one book that my ‘opponents’ have often urged me to read is Mere Christianity by C.S. Lewis. I had never done so, but when I found out that the whole thing was available online (here), I went ahead and read it—in stolen snippets of two days, at that; it’s short and a light read. My very brief conclusion is that C.S. Lewis is an entirely different brand of apologist from the raucous, idiot, Ray Comfort kind to which I have previously been exposed. I get every impression that he was being quite sincere and honest. He may also very well have been intelligent. —I say “may” because this book provides no evidence that he was, but nor do I think that it provides strong evidence that he wasn’t.

That said, in the early chapters of Mere Christianity, comes off as honest, sincere, quite possibly intelligent, and completely unconvincing and to all appearances dead wrong. (This review originally contained a part explaining why I consider it coherent to be intelligent, honest, and completely wrong; that aside grew into this.) So unconvincing and so wrong, in fact, that while I consider it entirely possible that he was intelligent, and while some of his fans may very well be very intelligent (with the same rationale), anyone who was convinced by it must have had their critical thinking faculties shut off for the day. Much as a palæontologist accepts a single fossil or a physicist a single relativistic experiment, you may accept Mere Christianity as fitting into a worldview, but it is no more sufficient to build a complete theory upon. Unlike fossils and physical experiments, however, Mere Christianity attempts logical arguments, and—well, we shall see how it succeeded.

The book is written in a compelling way—easy, conversational language, and a structure where each chapter builds directly and explicitly on the one before it. Thus, he starts off by establishing a universal moral law; shows that the universal law must reflect some underlying reality; shows that this underlying reality must be an Intelligence; shows that it must be an Intelligence rather like the Christian God—and so forth. He is not mealy-mouthed, nor needlessly offensive, nor does he sound insincere. All of this gives me a rather favourable view of him as a person.

As a logician and persuader, however, I can’t give him much respect. My initial reaction to the first few chapters was that, with some minor restructuring, they could easily be retitled according to which logical fallacy he built each chapter’s claim upon. Thus one early chapter took St. Anselm’s failed Ontological Argument and applied it to moral law: We can conceive of a moral law better than our own; therefore there must be a Perfect moral law. (Not true: We might have and fully grasp the ultimate moral law but fail to recognise that it’s perfect.) Another was based on Equivocation (descriptive natural laws with prescriptive moral laws). Another, while not a formal fallacy that I’m aware of, was based on equivocating percepts with objects: That is, he went from All humans feel that there is something rather like X to Therefore, there exists an X with some sort of independent reaction. (Nonsense! If we find that all humans feel X we have indeed discovered a fact, but it’s a fact about human brains, not about the world outside them.) These percepts, once reified, were deified in short order.

Unfortunately, the book went rather downhill from this point. In the early chapters, I can really respect what Lewis was trying to do. Of course, I find that his arguments were not in fact valid, but he clearly believed the premises were true, he obviously believed in his conclusion, and as I have said before and will gladly repeat, it is often very difficult to find flaws in your own inferences when they make a path whereby, as far as you can tell, you get from the right starting point to the right end point. And in these early chapters, I am inclined to agree that if his arguments had been valid and sound, as he believed, then he had some very right and very valuable things to say; and he does lay out his arguments, however flawed, clearly and lucidly.

But this, alas, was not to last. Having once established (in his mind) that there must be a deity that shares some important, basic traits with the god of Judeo-Christian mythology, he went on to implicitly assume a whole slew of Christian dogma, and he did it so suddenly and unselfconsciously that it took me a chapter or two before I went Hang on a minute…! It is as though, once you accept a good, omnipotent creator deity, Moses, the Ten Commandments, Jesus, Judas, and the whole cabaret just followed naturally. This was a huge disappointment—he didn’t even try to show his work in this part of the examination.

The redeeming aspect of this part of the work was that if you once accept his assumptions, a lot of the things he says are very cogent and sensible. But that is not much help if you haven’t accepted those assumptions! He also argues an awful lot by metaphor. This is fine—he manages to explain a number of very weird things in Christian dogma in a way that made a lot of sense to me. So far, so good. However, a critical feature of an explanation by metaphor is that you have to be able to show how it reduces back to the real issue. Again, Lewis doesn’t fail to do this—he never even attempts it. It felt very much as if it never occurred to him that this had to be explained.

And I found this very peculiar, because C.S. Lewis was by all accounts an atheist, and he was brought to believe in all these things. How did this happen? I feel as though he must have had more of a story to tell, because the argument he lays out is completely insufficient to take an intelligent person from atheism to Christianity. Even if his initial arguments had been sound, there just wasn’t a chain of logic available to bring an atheist any further than a sort of nebulous proto-Judeo-Christian monotheism with no specifics of ritual or dogma, let alone such esoteric notions as the Trinity (which, by the way, he explains in lucid, wonderful metaphor that he completely neglects to show to be equivalent to any underlying reality). I supppose Lewis, if he was an atheist before, must not have reached that point by skepticism so much as more specific disappointment with points of dogma.

The part of the entire book that I found the most rewarding to read was, and this might surprise you, the two chapters on Faith. Now, I make it no secret that I regard the concept of faith with derision and contempt—faith, as I generally see it used and defined, refers to belief without evidence, and in some circles (particularly US fundamentalists) even belief in spite of evidence, which is lunacy and the least ethical and virtuous thing you can possibly do without involving others. However, C.S. Lewis defines faith very differently. I can do the concept no better justice than to quote him:

Roughly speaking, the word Faith seems to be used by Christians in two senses or on two levels, and I will take them in turn. In the first sense it means simply Belief—accepting or regarding as true the doctrines of Christianity. That is fairly simple. But what does puzzle people-at least it used to puzzle me—is the fact that Christians regard faith in this sense as a virtue. I used to ask how on earth it can be a virtue—what is there moral or immoral about believing or not believing a set of statements? Obviously, I used to say, a sane man accepts or rejects any statement, not because he wants to or does not want to, but because the evidence seems to him good or bad. If he were mistaken about the goodness or badness of the evidence that would not mean he was a bad man, but only that he was not very clever. And if he thought the evidence bad but tried to force himself to believe in spite of it, that would be merely stupid.

Well, I think I still take that view. But what I did not see then—and a good many people do not see still—was this. I was assuming that if the human mind once accepts a thing as true it will automatically go on regarding it as true, until some real reason for reconsidering it turns up. In fact, I was assuming that the human mind is completely ruled by reason. But that is not so. For example, my reason is perfectly convinced by good evidence that anaesthetics do not smother me and that properly trained surgeons do not start operating until I am unconscious. But that does not alter the fact that when they have me down on the table and clap their horrible mask over my face, a mere childish panic begins inside me. I start thinking I am going to choke, and I am afraid they will start cutting me up before I am properly under. In other words, I lose my faith in anaesthetics. It is not reason that is taking away my faith: on the contrary, my faith is based on reason. It is my imagination and emotions. The battle is between faith and reason on one side and emotion and imagination on the other.

With this second definition of the word faith, it actually makes sense. What this teaches me is that when I next meet someone extolling the virtues of faith, I need to explicitly establish what, precisely, this person means, because he or she may not be referring to it in the sense that I am used to encountering it. If someone believes in the virtues of faith¹, they are beneath being reasoned with. Faith², on the other hand, is in fact a positive thing! I do not need to be persuaded of its virtue; I agree with it! On the other hand, faith² is not a way in which religion can be reached. If somebody tells me that You won’t find God by evidence; you just have to have faith, they are using faith¹ and I will continue to dismiss them. If they take offence at this, I can now not only explain why, but also point out that C.S. Lewis regarded that claim as stupid.

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.

The US National Institute of Health department, the National Centre for Complementary and Alternative Medicine (NC-CAM), whose aim is to find evidence for alternative medicine, found to its chagrin that alternative medicine doesn’t work. Key snippets:

Ten years ago the government set out to test herbal and other alternative health remedies to find the ones that work. After spending $2.5 billion, the disappointing answer seems to be that almost none of them do.

Echinacea for colds. Ginkgo biloba for memory. Glucosamine and chondroitin for arthritis. Black cohosh for menopausal hot flashes. Saw palmetto for prostate problems. Shark cartilage for cancer. All proved no better than dummy pills in big studies funded by the National Center for Complementary and Alternative Medicine. The lone exception: ginger capsules may help chemotherapy nausea.

As for therapies, acupuncture has been shown to help certain conditions [though if I read it aright, That finding was called into question when a later, larger study found that sham treatment worked just as well –ed.], and yoga, massage, meditation and other relaxation methods may relieve symptoms like pain, anxiety and fatigue.

…

…Critics say that unlike private companies that face bottom-line pressure to abandon a drug that flops, the federal center is reluctant to admit a supplement may lack merit — despite a strategic plan pledging not to equivocate in the face of negative findings.

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"There's been a deliberate policy of never saying something doesn't work. It's as though you can only speak in one direction," and say a different version or dose might give different results, said Dr. Stephen Barrett, a retired physician who runs Quackwatch, a web site on medical scams.

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Critics also say the federal center's research agenda is shaped by an advisory board loaded with alternative medicine practitioners. They account for at least nine of the board's 18 members, as required by its government charter. Many studies they approve for funding are done by alternative therapy providers; grants have gone to board members, too.

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[The Centre’s methodology] is opposite how other National Institutes of Health agencies work, where scientific evidence or at least plausibility is required to justify studies, and treatments go into wide use after there is evidence they work — not before.

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In a federally funded pilot study, 30 dieters who were taught acupressure regained only half a pound six months later, compared with over three pounds for a comparison group of 30 others. However, the study widely missed a key scientific standard for showing that results were not a statistical fluke.

In other words, NC-CAM, which was founded with the intent of finding evidence for the quackery that the sponsoring Senators were already convinced by (to look for a yes, in other words, rather than objectively assessing credibility), is perfectly happy to spend millions upon millions of US tax dollars on investigating ludicrous fantasies like distance faith healing, energy healing, and homeopathy (dollars that could be spent on valid research), is biased by a board of proponents, tends to publish lackluster studies with missing controls…and still can’t come up with a single positive result beyond noting that ginger may (may) help with nausea.

If that’s the best they can come up with the cards stacked unreasonably in their favour, then it’s time to pull the plug and spend the next $2.5 billion dollars on something useful.