Just as nature makes some men quick to anger, many other things can have the same effect. Some people get this way from illness or injury. Others from hard work, lost sleep, anxious nights, intense desires, and love. Anything that hurts the body or spirit makes a troubled mind ready to find fault. But these are just the starting points — the things that cause anger. Your habits of thinking have enormous power. If your habits are harsh, they make the problem worse. As for nature itself, it's hard to change. We can't alter the basic mix of elements we were born with. But knowledge can help this much: we should keep wine away from hot-tempered people. Plato thought wine should also be forbidden to boys, so that fire doesn't make fire fiercer.
But just as nature makes some men prone to anger, so there are many other causes which have the same power as nature. Some are brought into this condition by disease or bodily injury, others by hard work, long watching, nights of anxiety, ardent longings, and love: and everything else which is hurtful to the body or the spirit inclines the distempered mind to find fault. All these, however, are but the beginning and causes of anger. Habit of mind has very great power, and, if it be harsh, increases the disorder. As for nature, it is difficult to alter it, nor may we change the mixture of the elements which was formed once for all at our birth: yet knowledge will be so far of service, that we should keep wine out of the reach of hot-tempered men, which Plato thinks ought also to be forbidden to boys, so that fire be not made fiercer.