8. But let us pass by the infantine age, since we cannot question it as to what goes on within itself, while we have ourselves pretty well forgotten it. Let it suffice only for us hence to be certain, that when man has come to be able to think of the nature of his own mind, and to find out what is the truth, he will find it nowhere else but in himself. And he will find, not what he did not know, but that of which he did not think. For what do we know, if we do not know what is in our own mind; when we can know nothing at all of what we do know, unless by the mind?