What good men most biologists are, the tenors of the scientific world — temperamental, moody, lecherous, loud-laughing, and healthy. Your true biologist will sing you a song as loud and off-key as will a blacksmith, for he knows that morals are too often diagnostic of prostatitis and stomach ulcers. Sometimes he may proliferate a little too much in all directions, but he is as easy to kill as any other organism, and meanwhile he is very good company, and at least he does not confuse a low hormone productivity with moral ethics. The Log from the sea of Cortez

Pure and complete sorrow is as impossible as pure and complete joy. War and Peace

The plainest sign of wisdom is a continual cheerfulness: her state is like that of things in the regions above the moon, always clear and serene. Essays

Spiritual wants and instincts are as various in the human family as are physical appetites, complexions, and features, and a man is only at his best, morally, when he is equipped with the religious garment whose color and shape and size most nicely accomodate themselves to the spiritual complexion, angularities, and stature of the individual who wears it. A Connecticut Yankee in King Arthur's Court