Rush Rhees on the demands and scope of Wittgenstein’s Investigations

Wittgenstein did go through the [Philosophical] Investigations with me – some parts of it several times – before it was published. And although such understanding of it as I have has come more since his death, I should have understood less if I had not heard him read it and had him discuss it with me. This does not mean that I could speak about it with any authority at all. It means only that I agree that I could not get the hang of it and must give it up, if I had not had that help. (There are others who were not so lucky as I was, and who have no doubt understood it better, though.) Earlier drafts of various passages in it go back pretty far. Wittgenstein constantly tried to make his remarks more forceful, and also to shorten them. This meant that he demanded more from his readers. And of course most of his readers have not given what was needed. Here I am thinking above all of the bearing which these remarks in the Investigations have on other questions in philosophy and in logic. He thought that the same ‘line of thinking’, and in many ways the same problems, which come up in logic and the philosophy of mathematics, and also in metaphysics – the idea of the creation of the world and the idea of a Saviour – that these are really the same problems which he is discussing here in the Investigations. Wittgenstein himself had a genius for perceiving identities of this sort: it went together with his genius for recognizing problems where few or no one else would recognize them. And he thought that anyone who thought about what he has said in the Investigations, would come to realize that connexion – if he was giving any deep thought to them. I think it is clear that he was asking for more than most readers would be able to give or to do. And in some measure he may have expected this. (The idea that the Investigations is just an essay in philosophical psychology is one of the easiest and most short-sighted.)

from Wittgenstein and the Possibility of Discourse, 2^nd Ed., Ed. D.Z. Phillips, (Blackwell, 2006), 257.