In the republic of mediocrity, genius is dangerous.

Every church pretends to have found the exact truth. This is the end of progress. Why pursue that which you have? Why investigate when you know? Every creed is a rock in running water: humanity sweeps by it. Every creed cries to the universe, "Halt!" A creed is the ignorant Past bullying the enlightened Present. The ignorant are not satisfied with what can be demonstrated. Science is too slow for them, and so they invent creeds. They demand completeness. A sublime segment, a grand fragment, are of no value to them. They demand the complete circle... the entire structure.

The ideas of right and wrong change with the experience of the race, and this change is wrought by the gradual ascertaining of consequences - of results.

Liberty is the condition of progress. Without Liberty, there remains only barbarism. Without Liberty, there can be no civilization.

A fact never went into partnership with a miracle. Truth scorns the assistance of wonders. A fact will fit every other fact in the universe, and that is how you can tell whether it is or is not a fact. A lie will not fit anything except another lie.

The intellectual advancement of man depends on how often he can exchange an old superstition for a new truth.

Man must learn to rely upon himself. Reading bibles will not protect him from the blasts of winter, but houses, fires. and clothing will. To prevent famine, one plow is worth a million sermons, and even patent medicines will cure more diseases than all the prayers uttered since the beginning of the world.