The Church says the Earth is flat. But I know that it is round. For I have seen the shadow on the Moon. And I have more faith in a shadow than in the Church.

Cruelty hardens and degrades, kindness reforms and ennobles.

It is with men as with other things. The mullein needs only a year, but the oak a century, and the greatest men are those who have continued to grow as long as they have lived.

A believer is a bird in a cage, a freethinker is an eagle parting the clouds with tireless wing.

We have at last ascertained that miracles can be perfectly understood; that there is nothing mysterious about them; that they are simply transparent falsehoods.

Theology is not what we know about God, but what we do not know about Nature.

When the will defies fear, when duty throws the gauntlet down to fate, when honor scorns to compromise with death - that is heroism.