Few minds wear out; more rust out.
Loss of sincerity is loss of vital power.
Honesty is not only "the first step toward greatness," - it is greatness itself.
Living with a saint is more grueling than being one.
To death we owe our life; the passing of one generation opens a way for another.
Can that which is the greatest virtue in philosophy, doubt (called by Galileo the father of invention), be in religion what the priests term it, the greatest of sins?