Friday, April 28, 2017

Sober on Essentialist Explanations in Science

"My suggestion is that the gas's kinetic energy explains what it is for the gas to have the temperature it does. It does not explain why the gas has the temperature at the time in question. The relationship here is much like the one between a dispositional property and its physical basis. If zebras differ in fitness because of their leg structure, then there is a sense in which leg architecture explains fitness relationships. The relationship is not causal; it does not explain why those fitness values came into existence. Science not only explains why certain states of affairs and events come into existence; it also seeks to explain the nature of those events."

--Elliott Sober, The Nature of Selection, p. 75.

Note that explanation is hyperintensional, and that not just any necessarily coextensive term would work equally well in place of 'the gas's kinetic energy' here.

Wednesday, April 26, 2017

Laplace and Mereology

"We may regard the present state of the universe as the effect of its past and the cause of its future. An intellect which at a certain moment would know all forces that set nature in motion, and all positions of all items of which nature is composed, if this intellect were also vast enough to submit these data to analysis, it would embrace in a single formula the movements of the greatest bodies of the universe and those of the tiniest atom; for such an intellect nothing would be uncertain and the future just like the past would be present before its eyes." -- Laplace

My understanding is that Laplace's demon was primarily intended as a heuristic for understanding microphysical determinism. But there is a serious question (noted by or implicit in the work of a number of philosophers of science, e.g., Sober, Loewer, Albert) as to whether, in fact, "nothing" about the physical universe would escape the demon's knowledge. There is some ambiguity in what is meant by "submit these data to analysis," but intuitively it seems that the demon's abilities would only allow him to know all of the facts describable in microphysical terms. There is a real question then about whether this would amount to knowledge of all of the facts, including about mereologically composite objects, let alone about minds.

Would we need to add to the demon's capacities, then, some sort of additional "translation manual" to tell him which macro-states are being realized by the micro-physical states? And would this amount to a problem for a reductionist picture of the world? Maybe, maybe not.