Wednesday, August 10, 2005

Warning: Political Content

As some of us may recall from training in formal logic, one of the most common logical fallacies is post hoc, ergo propter hoc. This takes the following form: A preceded B; hence, A caused B. I'm not a compulsive stickler for formal logic, because we all leap to conclusions from time to time, and it's often necessary that we do so in the absence of complete information, in order to exercise what we call choice. Although proper use of logic has myriad practical and moral consequences, it's not my purpose to discuss those here. Suffice to say that where premises are insufficient to warrant a conclusion, whether because information is lacking, or because some crucial assumption is open to question, there is plenty of room for reasonable people to disagree, and this can even be a certain amount of fun. But one thing we may take away from consideration of the post hoc fallacy is that, even in jumping to the wildest conclusions on the flimsiest basis, it is always true that the cause precedes the effect. No one can reasonably hold what might be called the reverse post hoc principle, namely this: A follows B; therefore, A caused B. (You might be mistaken about when A actually occurred, thinking that it occurred prior to B, when it actually occurred after; but this is not the same thing. Clever students might wish to hold that B, therefore A could be a valid form of argument in a reversed-time world, or in some internally consistent alternative logical universe, but I am not so sure.) Those who seriously hold the reverse post hoc principle would soon be compelled to take up residence at Propeller Beany Estates, and even there they might be thought rather odd.

Examples of this mode of thinking might be the following:

  • The American civil rights movement caused the Civil War.
  • Hippies of the 1960s caused conformity in the 1950s.
  • Monty Python's Life of Brian was the source of Christianity.
  • Darwin's The Origin of Species caused the extinction of dinosaurs.
  • Douglas Fairbanks Jr. sired Douglas Fairbanks and Mary Pickford.

You can have fun making these up on your own, although personally I would not recommend spending more than a few minutes at it unless you are at work. The main point is this: it does not matter what facts you bring to bear to either the A variable or to the B variable, not even if you research for years and write volumes and volumes, because you will never ever be able to make your case. Why not? Because the cause happened after the effect. It's not an empirical argument, it's a logical contradiction. But of course you may run into the occasional armpit-sniffer who seriously contends that, for instance, it's obvious, and it is common knowledge, that the movie Life of Brian was made well before the founding of Christianity; that LoB was made in 100 B.C. and/or Christianity was founded in 1985. You are probably wasting your time talking with any such people, as they are more likely than not to maintain that any evidence of the relative ages of the movie and the religion is "phony," due to an extraordinary conspiracy to falsify evidence, which may or may not involve The Pope, multinational corporations, secret messages in heavy metal recordings, ultraviolet brainsuckers from Venus, and the I.R.S.

Recently it has been increasingly bruited about that Islamic jihad has been caused by the American War on Terror. In the normal course of events, one would merely point out that this is not logically possible. Reasonable people would yield on this point, and the few full-bore nutters who did not could be gently encouraged to go and play with their Twinkies, and to please clean themselves afterwards this time. But it now seems that the more the point is politely but firmly refuted, the more popular it becomes, to the extent that it has become an unavoidable commonplace, and not just here in silly Massachusetts.

The League of David (no relation to the David who occasionally appears on this blog) has recently sighed, taken two aspirin, sat down and compiled the necessary facts to demonstrate conclusively that Islamic jihad indeed has a very long tradition, and that that tradition, although it has been brought to bear on the United States on recent occasions, actually arose quite independently of this country, and quite a long while ago -- despite the evident need of some people in this country to believe that the universe revolves around them and their cherished little sins. In any event, it is a fine piece, and I commend it to one and all, although I daresay that those who are most in need of reading it will not, or cannot.

We will presently return to our regularly-scheduled self-contained fantasy world of Victoriana, Elgar, expeditions down the Nile, Italian zombies, nonsense verse, and college humor.