Abstract

Many scientists and philosophers of science think that beauty should play a role in theory selection. Physicists like Paul Dirac and Steven Weinberg explicitly claim that the ultimate explanations of the physical world must be beautiful. And philosophers of science like Peter Lipton say that we should expect the loveliest theory to also be the most likely. In this paper, I contend that these arguments from loveliness bear a striking similarity to Thomas Aquinas’ arguments from fittingness; both seem to presume that the most beautiful theory is also the most probable. To do this, I first explain the explanatory virtues that are commonly thought to be constitutive of a lovely theory. Second, I elucidate Aquinas’ arguments from fittingness and show how they work in light of his account of beauty. Lastly, I connect the two kinds of aesthetic arguments and show the extent to which they overlap.