Philosophy is like trying to open a safe with a combination lock: each little adjustment of the dials seems to achieve nothing, only when everything is in place does the door open.

Nowadays it is the fashion to emphasize the horrors of the last war. I didn't find it so horrible. There are just as horrible things happening all round us today, if only we had eyes to see them.

A philosopher who is not taking part in discussions is like a boxer who never goes into the ring.

Not only is there no guarantee of the temporal immortality of the human soul, that is to say of its eternal survival after death; but, in any case, this assumption completely fails to accomplish the purpose for which it has always been intended. Or is some riddle solved by my surviving forever? Is not this eternal life itself as much of a riddle as our present life?

With my full philosophical rucksack I can only climb slowly up the mountain of mathematics.

A wheel that can be turned though nothing else moves with it, is not a part of the mechanism.

What signs fail to express, their application shows. What signs slur over, their application says clearly.