With Kadri Vihvelin
Textbook definitions of ‘determinism’ that avoid appeal to the notion of nomological possibility are mistaken. To explain Determinism, we must invoke a distinction between states of the world that are and those that are not nomologically possible. It is plausible to suppose that nomological determinism, properly understood, entails counterfactual determinism. That is, to suppose that If the world is deterministic then, if it were different at any time, then it would have to be different at every other time. David Lewis’ theory of counterfactuals forces him to deny this. This is more evidence that his theory is wrong and that a rival theory is correct.
