"Every habit and faculty is formed or strengthened by the corresponding act – walking
makes you walk better, running makes you a better runner. If you want to be literate,
read, if you want to be a painter, paint. Go a month without reading, occupied with
something else, and you’ll see what the result is. And if you’re laid up a mere ten
days, when you get up and try to talk any distance, you’ll find your legs barely able to
support you. So if you like doing something, do it regularly; if you don’t like doing
something, make a habit of doing something different. The same goes for the affairs
of the mind… So if you don’t want to be hot-tempered, don’t feed your temper, or
multiply incidents of anger. Suppress the first impulse to be angry, then begin to count
the days on which you don’t get angry. ‘I used to be angry every day, then only every
other day, then every third…’ If you resist it a whole month, offer God a sacrifice,
because the vice begins to weaken from day one, until it is wiped out altogether. ‘I
didn’t lose my temper this day, or the next, and not for two, then three months in
succession.’ If you can say that, you are now in excellent health, believe me."
– Epictetus,
Discourses, 2.18