Let your love be stronger than your hate or anger. Learn the wisdom of compromise, for it is better to bend a little than to break.

Statistical thinking will one day be as necessary for efficient citizenship as the ability to read and write!

Books-bright windows in this life of ours, lit by the shining souls of men.

It is a law of nature we overlook, that intellectual versatility is the compensation for change, danger, and trouble. An animal perfectly in harmony with its environment is a perfect mechanism. Nature never appeals to intelligence until habit and instinct are useless. There is no intelligence where there is no change and no need of change. Only those animals partake of intelligence that have a huge variety of needs and dangers.

Rest enough for the individual man, too much and too soon, and we call it death. But for man, no rest and no ending. He must go on, conquest beyond conquest. First this little planet and all its winds and ways, and then all the laws of mind and matter that restrain him. Then the planets about him, and, at last, out across immensities to the stars. And when he has conquered all the deep space, and all the mysteries of time, still he will be beginning.

Biologists can be just as sensitive to heresy as theologians.

The Athenian democracy suffered much from that narrowness of patriotism which is the ruin of all nations.