Philosophy is not a theory but an activity.

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.

Never stay up on the barren heights of cleverness, but come down into the green valleys of silliness.

Language is a part of our organism and no less complicated than it.

Philosophy limits the thinkable and therefore the unthinkable.

Philosophy hasn't made any progress? - If somebody scratches the spot where he has an itch, do we have to see some progress? Isn't genuine scratching otherwise, or genuine itching itching? And can't this reaction to an irritation continue in the same way for a long time before a cure for the itching is discovered?

For a large class of cases - though not for all - in which we employ the word meaning it can be explained thus: the meaning of a word is its use in the language.