PHYSICAL AND METAPHYSICAL NECESSITY

  I propose a different way of thinking about metaphysical and physical necessity: namely that the fundamental notion of necessity is what would ordinarily be called “truth in all physically possible worlds”– a notion which includes the standard physical necessities and the metaphysical ones as well; I suggest that the latter are marked off not as a stricter kind of necessity but by their epistemic status. One result of this reconceptualization is that the Descartes‐Kripke argument against naturalism need no longer trouble us. I end by relating the difference between my view and the standard view to the question, whether there could have been a different world than ours.