Now it is manifest that we have no idea of a conception when it is impossible. And when the knowledge “of something is only hypothetical, even if we have the idea of it, we do not directly contemplate that idea, for such a conception is known only in the same way as conceptions that contain a hidden contradiction; and if the conception is indeed possible, it is not by this kind of knowledge that we learn its possibility. For instance, when I am thinking of a thousand or of a chiliagon, I frequently do it without contemplating the idea. Even if I say a thousand is ten times a hundred, I frequently do not trouble to think what ten and a hundred are, because I assume that I know, and I do not consider it necessary to stop just at present to conceive of them. Therefore it may well happen, as it in fact does happen often enough, that I am mistaken in regard to a conception which I assume, or believe that I understand, although it is in fact impossible or at least is incompatible with others with which I join it, and whether I am mistaken or hot, this hypothetical method of conception remains the same. It is, then, only when our knowledge is clear in regard to confused conceptions, and when it is intuitive in regard to those which are distinct, that we see its entire idea.