Hero-worship is strongest where there is least regard for human freedom.

Whatever fosters militarism makes for barbarism; whatever fosters peace makes for civilization.

In science the important thing is to modify and change one's ideas as science advances.

The defects of the children mirror the defects of the parents.

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.

Volumes might be written upon the impiety of the pious.

To play billiards well was a sign of an ill-spent youth