The actualism/possibilism debate in ethics is traditionally formulated in terms of whether true counterfactuals of freedom about the future (true subjunctive conditionals concerning what someone would freely do in the future if they were in certain circumstances) even partly determine an agent's present moral obligations. But the very assumption that there are true counterfactuals of freedom about the future conflicts with the idea that freedom requires a metaphysically open future. We develop probabilism as a solution to the actualism/possibilism debate, a solution that accommodates an open future requirement for freedom. We argue that probabilism resolves the conflicting intuitions that arise between actualists and possibilists and maintains certain distinct advantages over actualism and possibilism.

In this critical review, I focus on two things. First, I respond to Stang’s interpretation of Descartes, according to which Descartes’ endorsement of his ontological argument commits him to possibilism, the doctrine that there are, or at least could be, non-existent individuals. My response consists in presenting a version of Descartes’ argument the acceptance of which does not require the acceptance of possibilism. The second thing I focus on is Stang’s claim that Kant distinguishes several kinds of real possibility. I raise worries about Stang’s formulations of various doctrines of real possibility, and I preliminarily explore how real essence and ground are connected with the various kinds of real necessity Stang’s Kant recognizes.