Friday, September 08, 2006

Tautological Wishful Retroduction and Progress in Iraq

While we're on a roll of new fallacies...

Heard a general interviewed on Morning Edition this morning and when asked why the number of improvised explosive devices (also known as bombs designed to kill American troops and set off in attacks on American troops) have been increasing each month, he gave the party line (guess which party) that the number of attacks were increasing because we are making progress in Iraq -- this progress, he cited the election as the central example, makes the members of insurgency nervous, sensing their days are numbered and they are thus forced to "put the pedal down" (his words).

What we see here is an example of what I call "wishful retroduction." Retroduction is a legitimate form of reasoning proposed by Charles Sanders Peirce in which the explanatory power is take to have logical force. It works this way:

Curious phenomenon e occurred
If hypothesis h were true, it would explain why e occurred
Therefore, there is some reason to consider the possibility of h being true

Notice that retroduction is a very weak form of inference. We do not get that h is true or even probably true, but that h is worth considering, pursuing, keeping in play. the weakness comes from a fact pointed out by John Stuart Mill that there are always more possible explanations that can be thought up. To steal an example from Peter Achinstein which I love very much...if I walk out to my car in the morning and it won't start, it might be true that a monkey escaped from the zoo that night, siphoned the gas out of my tank and substituted crushed bananas. But simply because it would explain if it were true, doesn't by itself give me warrant for believing that it is in fact true.

The fallacy of wishful retroduction is taking a possible explanation and asserting it as THE explanation because I want it to be. And this is what the general is doing. He gives one possible explanation among several. Another might be that the insurgency is getting stronger. A third would be that the insurgency is remaining at the same strength, but acquiring more materials. A fourth would be that the insurgency has been defeated, but Oliver Stone has found financing from the Freemasons and the Elders of Zion in order to make it seem as if there was an insurgency just to distract attention away from the fact that he really killed JFK. His explanation may, in fact, be right, but for that we would need additional evidence that his explanation is the most likely to be true. One concern for his line is that he'll need to find support for the claim that an election that happened quite a while ago continues to have the causal efficacy needed to continue to give rise to greater and greater stress amongst insurgents.

But this case is even more interesting because the explanation he cites, progress in Iraq, would be a possible explanation not only for curious event e, but also a possible operative explanation for a world in which e was false. On twin Earth, the general's doppelganger was asked why IED attacks were not increasing in Twin Iraq and he cites progress in Twin Iraq, especially the elections. So if the attacks increase, it is to be explained by the fact that we are making progress and if the attacks decrease it is to be explained by the fact that we are making progress.

Of course, this is putting words in the general's mouth, he could say that a decreasing number of attacks would be a sign of a strengthening insurgency. This sort of reasoning is not unknown. In the writings of Samuel Hahnemann, the creator of homeopathy, for example, there is the "law of infinitesmals" wherein the more diluted a homeopathic remedy gets, the more curative power it possesses. When there is not even a detectable trace of the active chemical agent, the diluted solution is at its strongest. In the same way, perhaps an insurgency that did not attack at all would be the sign of complete failure in Iraq.

But more or fewer are not the only possibilities. I wonder what he would say if the number of attacks happened to be exactly the same month after month after month. Of course, that would be weird, Oliver Stone knows better than that.