Men and governments must act to the best of their ability. There is no such thing as absolute certainty but there is assurance sufficient for the purposes of human life.

There is an imaginary circle drawn around every human being, over which no government should be able to step.

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

Over one's mind and over one's body the individual is sovereign.

It often happens that the universal belief of one age of mankind — a belief from which no one was, nor without an extraordinary effort of genius and courage, could at that time be free — becomes to a subsequent age so palpable an absurdity, that the only difficulty then is to imagine how such a thing can ever have appeared credible.

It is questionable if all the mechanical inventions yet made have lightened the day's toil of any human being.

The ne plus ultra of wickedness ... is embodied in what is commonly presented to mankind as the creed of Christianity.