Even in civilized mankind faint traces of monogamous instinct can be perceived.

Collective wisdom, alas, is no adequate substitute for the intelligence of individuals. Individuals who opposed received opinions have been the source of all progress, both moral and intellectual. They have been unpopular, as was natural.

When there are rational grounds for an opinion, people are content to set them forth and wait for them to operate. In such cases, people do not hold their opinions with passion; they hold them calmly, and set forth their reasons quietly. The opinions that are held with passion are always those for which no good ground exists; indeed the passion is the measure of the holder's lack of rational conviction.

Indemnity for the past and security for the future.

Frege has the merit of ... finding a third assertion by recognising the world of logic which is neither mental nor physical.

The place of the father in the modern suburban family is a very small one, particularly if he plays golf.

Remote from human passions, remote even from the pitiful facts of nature, the generations have gradually created an ordered cosmos [mathematics], where pure thought can dwell in its natural home.