I refuse to engage in an intellectual battle with an unarmed man.

Since I have introduced this term I had always a bad conscience. . . . I cannot help to feel it strongly and I am unable to believe that such an ugly thing should be realized in nature.

I know that it is a hopeless undertaking to debate about fundamental value judgements. For instance, if someone approves, as a goal, the extirpation of the human race from the earth, one cannot refute such a viewpoint on rational grounds. But if there is agreement on certain goals and values, one can argue rationally about the means by which these objectives may be obtained.

A permanent peace cannot be prepared by threats but only by the honest attempt to create a mutual trust. However strong national armaments may be, they do not create military security for any nation nor do they guarantee the maintenance of peace.

Man can find meaning in life only through devoting himself to society.

I prefer to make up my own quotes and attribute them to very smart people, so that I can use them to win arguments

What distinguishes the language of science from language as we ordinarily understand the word? ... What science strives for is an utmost acuteness and clarity of concepts as regards their mutual relation and their correspondence to sensory data.