Our ideas must be as broad as Nature if they are to interpret Nature.

For strange effects and extraordinary combinations we must go to life itself, which is always far more daring than any effort of the imagination.

Well, I'm a bacteriologist, you know. I live in a nine-hundred-diameter microscope. I can hardly claim to take serious notice of anything that I can see with my naked eye.

Violence is sometimes a duty.

The emotional qualities are antagonistic to clear reasoning.

I carry my own church about under my own hat," said I. "Bricks and mortar won't make a staircase to heaven. I believe with your Master that the human heart is the best temple.

horses: dangerous on both ends and crafty in the middle