"A man is really ethical only when he obeys the constraint laid on him to aid all life which he is able to help, and when he goes out of his way to avoid injuring anything living. He does not ask how far this or that life deserves sympathy as valuable in itself, nor how far it is capable of feeling. To him life as such is sacred. If he goes out into the street after a rainstorm and sees a worm which has strayed there, he reflects that it will certainly dry up in the sunshine if it does not quickly regain the damp soil into which it can creep, and so he helps it back from the deadly paving stone into the lush grass. Should he pass by an insect which has fallen into a pool, he spares the time to reach a leaf or stalk on which it may clamber and save itself."
Albert Schweitzer (1875-1965), missionary, physician, 1952 Nobel Peace Prize