Be bold, be bold, and everywhere be bold.

This survival of the fittest implies multiplication of the fittest.

The cruelty of a Fijian god, who, represented as devouring the souls of the dead, may be supposed to inflict torture during the process, is small compared with the cruelty of a God who condemns men to tortures which are eternal.

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.

Progress, therefore, is not an accident, but a necessity…It is a part of nature.

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.

Education is preparation to live completely.