Elsewhere I was getting into a debate with a presupposition apologist and decided to steer things in the direction of actual philosophical presuppositions.
That got into what presuppositions are, basically thing we presuppose or take for granted. But that raised the question as to why we would presuppose what we do? For instance we generally presuppose that the world around us is real rather than presupposing that it's all an illusion and we are brains in vats. But why would we presuppose the one but not the other?
And since I know he loves these sorts of topics I will tag in @Moegreche
