Using four principles common to several theories about possible worlds, It is argued that the necessary existence of a divine being that is essentially omnipotent, Omniscient, And morally perfect is impossible. The central argument employs the premise that there are possible worlds that any divine being ought not to actualize (because of their evil contents). This premise is then defended on the grounds that the same sort of justification that we give for other modal statements that we accept can be (...) given for modal statements which entail the premise. It is concluded that we must reject the guiding principle that gives rise to the traditional theistic concept, Viz., That if a property p of an individual is an excellence of it and hence its having p is good, Then its having p necessarily or essentially is better. (shrink)