Historical knowledge is indispensable for those who want to build a better world.

People do not cooperate under the division of labor because they love or should love one another. They cooperate because this best serves their own interests. Neither love nor charity nor any other sympathetic sentiments but rightly understood selfishness is what originally impelled man to adjust himself to the requirements of society, to respect the rights and freedoms of his fellow men and to substitute peaceful collaboration for enmity and conflict.

The criterion of truth is that it works even if nobody is prepared to acknowledge it.

The philosophy called individualism is a philosophy of social cooperation and the progressive intensification of the social nexus.

Human civilization is not something achieved against nature; it is rather the outcome of the working of the innate qualities of man.

Scientific research sooner or later, but inevitably, encounters something ultimately given that it cannot trace back to something else of which it would appear as the regular or necessary derivative. Scientific progress consists in pushing further back this ultimately given.