Page:Schlick - Gesammelte Aufsätze (1926 - 1936), 1938.djvu/263

 might become inextricably complicated, if in psychological reality it were not shortened and simplified by habit and instinct. But after the meaning has been grasped, and the necessary steps towards the verification of the proposition have been taken, there is, in principle no difficulty in ascertaining, whether the structures of the propositions and the fact are the same or not.

I can see with one glance that the ring is lying on the book and not on a plate and that the book is not lying on the ring. In the case of real knowledge or material truth, which we have just been considering, it is necessary to find the meaning of the proposition first (which is the same as finding the way of its verification) and then we can look to see wether it is true or not. But when we have to do with analytic judgments, or tautologies, which is the case of formal truth, the matter is much simpler. In this case the grasping of the meaning and the verification are not two processes which follow each other; there is only one process which yields meaning as well as truth. For if I know the meaning of the proposition I know also that it is tautological and therefore know that it is true.

This disposes of certain sceptical arguments which have sometimes been brought forward against analytic judgments. It has been said that the human mind is so weak that it cannot be sure of the truth of tautologies even. For however short the process may be by which I convince myself of the truth of a tautological statement — do I not have to keep in mind the exact signification of the terms occuring in it, and the connection between them? Do I not have to remember all the definitions involved? and is it not just possible that my memory has just failed me during these few seconds since it does happen that we sometimes forget a fact from one minute to the next? So how can I be sure of anything ?

These difficulties have occasionally been emphasised to such an extent that the analytic judgment has declared to be the most difficult problem of epistemology.

In reality there is no problem that would raise any difficulties for Logic. Our answer to those sceptical doubts is simply this: If during the short process of thinking we should forget the signification of the words (perhaps without knowing it) the consequence would be that we are unable to understand the meaning of the sentence. We have no proposition at all, but just an empty series of falsity. There is a proposition only after we have understood the