Alex Rosenberg

An examination of the foundations of Elliot Sober's philosophy of biology as reflected in his introductory textbook of that title reveals substantial and controversial philosophical commitments. Among these are the claim that all understanding is historical, the assertion that there are biological laws but they are necessary truths, the view that the fundamental theory in biology is a narrative, and the suggestion that biology adverts to ungrounded probabilistic propensities of the sort to be met with elsewhere only in quantum mechanics

That biology provides explanations is not open to doubt. But how it does so must be a vexed question for those who deny that biology embodies laws or other generalizations with the sort of explanatory force that the philosophy of science recognizes. The most common response to this problem has involved redefining law so that those grammatically general statements which biologists invoke in explanations can be counted as laws. But this terminological innovation cannot identify the source of biology's explanatory power. I argue that because biological science is historical, the problem of biological explanation can be assimilated to the parallel problem in the philosophy of history, and that the problem was solved by Carl Hempel. All we need to do is recognize that the only laws that biology—in all its compartments from the molecular onward—has or needs are the laws of natural selection.