His [Marx's] most explosive and indeed most original contribution to the cause of revolution was that he interpreted the compelling needs of mass poverty in political terms as an uprising, not for the sake of bread or wealth, but for the sake of freedom as well.

Mathematics, the non-empirical science par excellence . . . the science of sciences, delivering the key to those laws of nature and the universe which are concealed by appearances.

Nobody is the author or producer of his own life story ... somebody began it and is its subject in the twofold sense, namely, its actor and sufferer ... but nobody is the author.

the fateful equating of power with violence, of the political with government, and of government with a necessary evil has begun.

Promises are the uniquely human way of ordering the future.

Ideas, as distinguished from events, are never unprecedented.

In order to go on living one must try to escape the death involved in perfectionism.