It must be admitted that the conception of virtue cannot be separated from the conception of happiness-producing conduct.

This survival of the fittest which I have here sought to express in mechanical terms, is that which Mr. Darwin has called "natural selection", or the preservation of favoured races in the struggle for life.

Agnostics are people who, like myself, confess themselves to be hopelessly ignorant concerning a variety of matters, about which metaphysicians and theologians, both orthodox and heterodox, dogmatize with the utmost confidence.

Education is preparation to live completely.

Music must take rank as the highest of the fine arts - as the one which, more than any other, ministers to human welfare.

A function to each organ, and each organ to its own function, is the law of all organization.

Of all the knowledge, that most worth having is knowledge about health! The first requisite of a good life is to be a healthy person.