“None of this should, however, lighten the heart of anybody in
; not even a little. In particular, I’ve provided not the slightest reason to doubt the central Darwinist theses of the common origin and mutability of species. Nor have I offered the slightest reason to doubt that we and chimpanzees had (relatively) recent common ancestors. Nor I do suppose that the intentions of a designer, intelligent or otherwise, are among the causally sufficient conditions that good historical narratives would appeal to in order to explain why a certain kind of creature has the phenotypic traits it does…It is, in short, one thing to wonder whether evolution happens; it’s quite another thing to wonder whether adaptation is the mechanism by which evolution happens.” ('Against Darwinism') Kansas
1) Natural selection via adaptationism is plausible only if it can distinguish between the selection of creatures that happen to express some phenotype, and those that are selected for expressing some phenotype.
2) This distinction rides on the plausibility of relevant counterfactuals.
3) There are only(!) two suggested ways to make sense of such counterfactuals: a) taking the phrase ‘mother nature’ quite literally; or b) positing laws of selection.
Fodor just asserts that these are the two options, but I’ve not found anyone disputing this. Now, 3a can’t be right, because there is no mind governing selection (again, this is just an assumption, but it’s surely right). To use Fodor’s example: Granny sells zinnias at the market, and selects them for their high prices. The high-priced zinnias happen to come with large roots. If we want to decide whether large roots, or high prices, are selected for, we just ask ourselves whether Granny would sell high priced plants with small roots. Of course she would. Thus, high-price is selected for, and large roots (in this world) just happen to be selected. This is all fine and well only because Granny has a mind, and she is making the choices. But nature does not have a mind, so 3a can’t be right.
Eliot Sober asks, why is this a problem? Once we do control for environment, isn’t there a necessary answer for which one wins out? The contention between Fodor and Sober seems to be on the role and status of laws in science. For instance, economists might argue that, all things being equal, an increase in the money supply will lead to inflation. Of course, there are so many intervening variables in the real world that this correlation rarely if ever holds, and when it does hold, there is always someone who can argue that the correlation is accidental, not lawful. In other words, all things are never equal, so in what sense can we call this a ‘law’ that relates increases in the money supply to inflation? At this point, I think that the debate becomes somewhat ad hoc. Economists will respond, as Sober does, by saying that they are constructing models, that the models help both to predict and explain phenomena, and that whether you want to call the rule-sets that govern variables in a model ‘laws’ or not is just a function of how strongly you want to interpret ‘natural law.’So, the contention seems to be, when we can something determinate in terms of natural selection only by specifying a context, whether we should count this a law or not, and this in term seems to ride upon how 'universal' you want your 'laws of nature' to be. For something to be a law, must it hold unconditionally across the entire universe, or can may one still speak of a law even when conditions and contexts have to be set? It's a very interesting question--it seems to me that most sciences now are fine talking about models rather than laws--but I don't think that one is crazy for coming down either way.