Did Reason Evolve In Order To Win Arguments?

Not likely, but there's this.

I don't pay much attention to this sort of thing, because it is so fashionable to promote the line that humans are irrational. There is, of course, interesting stuff in the mix, but the current pop-psych inclination seems to be to breathlessly promote every study that seems to impugn human reason.

Then, of course, there's the fact that you can't trust newspaper science writing at all. So until I dig up the relevant issue of BBS, I doubt that I have a very good idea what Mercier and company are really arguing.

Some obvious points, however:

1. Confirmation bias doesn't seem to play much of a role in winning arguments. Note that confirmation bias does not merely affect us when we have some stake in the outcome, nor merely with regard to propositions we advocate. Rather, we are plagued by confirmation bias even when we have no stake in the proposition at issue. It also makes us more apt to believe the propositions advanced by other people. So the hypothesis in question seems to have no advantage with regard to explaining one of our most significant cognitive flaws.

2. Intelligence is expensive (in evolutionary terms); it is also a kind of general-purpose ability. It seems prima facie unlikely that evolution would spend so profligately on an ability with such a narrow goal, when there are so many other things that intelligence is good for. The more reasonable hypothesis is the more ordinary one: intelligence is good for solving problems generally, and persuading others is just one type of problem among many others.

3. The worst thing about hypotheses like this is that evolutionary psychologists seem incapable of resisting illegitimately drawing normative conclusions. Witness the claim that we can't improve people's reasoning because it is doing "exactly what it is supposed to do." No. At best, it is doing what it evolved to do; that's quite different. Furthermore, intelligence has almost certainly been selected for largely because it allows for problem-solving generally, and that means that, if such things have functions, then its function is likely to be problem-solving.

This is all off the top of my head, and that's a dumb place for things to come from...so take it all with a grain of salt. But the non-stop parade of this kind of stuff in the NYT and elsewhere is rather annoying me. After more thought, I might retract some of the above.

Whoops...there I go trying to figure out the truth, rather than persuade people...