As the strata of the earth preserve in succession the living creatures of past epochs, so the shelves of libraries preserve in succession the errors of the past and their expositions, which like the former were very lively and made a great commotion in their own age but now stand petrified and stiff in a place where only the literary palaeontologist regards them.

Our life is a loan received from death with sleep as the daily interest on this loan.

The fruits of Christianity were religious wars, butcheries, crusades, inquisitions, extermination of the natives of America, and the introduction of African slaves in their place.

They tell us that suicide is the greatest piece of cowardice... that suicide is wrong; when it is quite obvious that there is nothing in the world to which every man has a more unassailable title than to his own life and person.

Still, instead of trusting what their own minds tell them, men have as a rule a weakness for trusting others who pretend to supernatural sources of knowledge.

The alchemists in their search for gold discovered many other things of greater value.

It often happens that we blurt out things that may in some kind of way be harmful to us, but we are silent about things that may make us look ridiculous; because in this case effect follows very quickly on cause.