 This is an argument that has in fact been made by several authors. Descartes, for one, appears to have argued that God is such an agent (Curley 1984). A genuinely omnipotent being, one might argue, should be able to perform any act whatsoever, even the impossible ones. This view of omnipotence is contentious, but it is not clear that it should be ruled out formally, by the very analysis of ability, as (MA) does. Spencer (2017) argues that even non-omnipotent agents may sometimes have the ability to perform acts that they do not perform at any possible world.