 If we follow this terminology we get eight modal categorical sentences, which we can raise to twelve if the notion of possibility is added. If we then perform the same calculation as before, taking into account the four figures and also the non-modal propositions, we get either 6,912 or 16,384 possible moods. It would be a gargantuan task, of course, to go through them all and see which ones are valid. Accordingly, Aristotle limits his discussion to those modal syllogisms whose assertoric counterparts are valid, as did most medieval logicians.