Aristotle, in his broad and moderate way, though he believed virtue alone to possess intrinsic value, yet allowed to external goods and circumstances a place in the scheme of life. The Stoics asserted that virtue alone is good, vice alone evil, and that all else is absolutely indifferent. Poverty, sickness, pain, and death, are not evils. Riches, health, pleasure, and life, are not goods. A man may commit suicide, for in destroying his life he destroys nothing of value. Above all, pleasure is not a good. One ought not to seek pleasure. Virtue is {351} the only happiness. And man must be virtuous, not for the sake of pleasure, but for the sake of duty. And since virtue alone is good, vice alone evil, there followed the further paradox that all virtues are equally good, and all vices equally evil. There are no degrees. Virtue is founded upon reason, and so upon knowledge. Hence the importance of science, physics, logic, which are valued not for themselves, but because they are the foundations of morality. The prime virtue, and the root of all other virtues, is therefore wisdom. The wise man is synonymous with the good man. From the root-virtue, wisdom, spring the four cardinal virtues, insight, bravery, self-control, justice. But since all virtues have one root, he who possesses wisdom possesses all virtue, he who lacks it lacks all. A man is either wholly virtuous, or wholly vicious. The world is divided into wise men and fools, the former perfectly good, the latter absolutely evil. There is nothing between the two. There is no such thing as a gradual transition from one to the other. Conversion must be instantaneous. The wise man is perfect, has all happiness, freedom, riches, beauty. He alone is the perfect king, statesman, poet, prophet, orator, critic, physician. The fool has all vice, all misery, all ugliness, all poverty. And every man is one or the other. Asked where such a wise man was to be found, the Stoics pointed doubtfully at Socrates and Diogenes the Cynic. The number of the wise, they thought, is small, and is continually growing smaller. The world, which they painted in the blackest colours as a sea of vice and misery, grows steadily worse.