Excellence is an art won by training and habituation. We do not act rightly because we have virtue or excellence, but we rather have those because we have acted rightly. We are what we repeatedly do. Excellence, then, is not an act but a habit.
This quote is often misattributed to Aristotle because the concepts behind the quote are his. Apparently some of the phrases in the quote come from Will Durant (The quoted phrases within Durants quotation are from Aristotle's Nicomachean Ethics, Book II, 4; Book I, 7. ): "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'; 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.'" (p.76 in 'Ch. II: Aristotle and Greek Science; part VII: Ethics and the Nature of Happiness' in The Story of Philosophy: The Lives and Opinions of the World's Greatest Philosophers, 1926, Simon & Schuster, 1991). The misattribution , therefore, seems to come from taking Durant's summation of Aristotle's ideas as being the words of Artistotle himself.
