No one can be perfectly free till all are free; no one can be perfectly moral till all are moral; no one can be perfectly happy till all are happy.

Civilization is a progress from an indefinite, incoherent homogeneity toward a definite, coherent heterogeneity.

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.

In the supremacy of self-control consists one of the perfections of the ideal man.

When men hire themselves out to shoot other men to order, asking nothing about the justice of their cause, I don't care if they are shot themselves.

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

Our lives are universally shortened by our ignorance.