Such are the differences among human beings in their sources of pleasure, their susceptibilities of pain, and the operation on them of different physical and moral agencies, that unless there is a corresponding diversity in their modes of life, they neither obtain their fair share of happiness, nor grow up to the mental, moral, and aesthetic stature of which their nature is capable.

The great creative individual . . . is capable of more wisdom and virtue than collective man ever can be.

Induction is a process of inference; it proceeds from the known to the unknown.

He who does anything because it is the custom, makes no choice.

The despotism of custom is everywhere the standing hindrance to human advancement.

Truth emerges from the clash of adverse ideas.

When one's ideas are not challenged, one's ability to defend them weakens.