The Story of Philosophy

by Will Durant

The golden mean, however, is not, like the mathematical mean, an exact average of two precisely calculable extremes; it fluctuates with the collateral circumstances of each situation, and discovers itself only to mature and flexible reason. Excellence is an art won by training and habituation: we do not act rightly because we have virtue or excellence, but we rather have these because we have acted rightly; “these virtues are formed in man by his doing the actions”;50 we are what we repeatedly do. Excellence, then, is not an act but a habit: “the good of man is a working of the soul in the way of excellence in a complete life; . . . for as it is not one swallow or one fine day that makes a spring, so it is not one day or a short time that makes a man blessed and happy.”