'Imagine a person whose memory could not retain what the word 'pain' meant-so that he constantly called different things by that name-but nevertheless used the word in a way fitting in with the usual symptoms and presuppositions of pain'-in short he uses it as we all do. Here I should like to say: a wheel that can be turned though nothing else moves with it, is not part of the mechanism.

It seems to me that, in every culture, I come across a chapter headed 'Wisdom.' And then I know exactly what is going to follow: 'Vanity of vanities, all is vanity.'

The sense of the world must lie outside the world... What we cannot speak about we must remain silent about... What can be described can happen too, and what is excluded by the laws of causality cannot be described.

Always get rid of theory private object in this way: assume that it constantly changes, but that you do not notice the change because your memory constantly deceives you.

The real question of life after death isn't whether or not it exists, but even if it does what problem this really solves.

Humor is not a mood but a way of looking at the world. So if it is correct to say that humor was stamped out in Nazi Germany, that does not mean that people were not in good spirits, or anything of that sort, but something much deeper and more important.

You must always be puzzled by mental illness. The thing I would dread most, if I became mentally ill, would be your adopting a common sense attitude; that you could take it for granted that I was deluded.