"When you let your attention slide for a bit, don't think you will get back a grip on it whenever you wish--instead, bear in mind that because of today's mistake everything that follows will be necessarily worse.... Is it possible to be free from error? Not by any means, but it is possible to be a person always stretching to avoid error. For we must be content to at least escape a few mistakes by never letting our attention slide." --EPICTETUS, DISCOURSES, 4.12.1; 19"