Abstract

Wilfrid Sellars [1962: 1] described philosophy as an attempt to ‘understand how things in the broadest possible sense of the term hang together in the broadest possible sense of the term’. But it is distinctive of philosophy that many of us are interested not only in how the world is but in ways that it could be. That is, philosophy is concerned with facts about modality. Some of the most important arguments in philosophy hinge on modal premises, and philosophers have typically assumed special expertise in evaluating these modal premises. Replicating Goldvarg and Johnson-Laird’s [2000] study of modal illusions, we show that training in mathematics and not philosophy predicts success in overcoming such illusions (n = 395). This study is the first to test the modal expertise of professional philosophers directly. Our findings undermine claims to modal expertise. Philosophical training does not inoculate expert philosophers against basic mistakes in modal judgment.