 (3) The third area in which counterpossible reasoning comes into play are metaphysical disputes (and more broadly, any philosophical dispute whose subject matter is necessarily true or necessarily false). Much metaphysical talk is made with our quantifiers “wide open”, that is, aiming at stating truths about all that there was, is, or could possibly be. This is evident in modal ontology, when people advance a theory on the totality of worlds and on their nature. But other metaphysical debates easily come to mind. Suppose a philosopher wants to evaluate metaphysical theories which she considers wrong (say, in order to draw unpalatable consequences by way of criticism), such as Spinoza’s monism or Hegel’s metaphysics of the Absolute. She must envisage situations where such metaphysics are correct and wonder what would be the case according to them: situations at which there is only one substance, or at which the Absolute Geist necessarily shapes the teleological development of history. These situations will be, under the hypotheses we have made, impossible worlds.