And yet the greatness of the interval which separates the Stoics even from the Cynics becomes at once apparent on considering the relation of Aristo to the rest of the Stoic School. In refusing to meddle with natural or mental science, or even with ethical considerations at all, Aristo faithfully reflects the principles of Antisthenes. In asserting the unity of virtue to such an extent that all virtues are merged in one, he was only repeating similar expressions of Antisthenes. In denying any difference in value to things morally indifferent, and in placing the highest morality in this indifference, he was, according to the older writers, reasserting a Cynic tenet. [1036] Conversely in denying these statements, as the great majority of Stoics did, the points are indicated in which Stoicism differed from Cynicism. [1037] In the feeling of moral independence, and in invincible strength of will, the Cynic is opposed to the whole world; he needs for virtue no scientific knowledge of the world and its laws; he regards nothing external to himself; he allows nothing to influence his conduct, and attaches value to nothing; but, in consequence, he remains with his virtue confined to himself; virtue makes him independent of men and circumstances, but it has neither the will nor the power to interpose effectively in the affairs of life, and to infuse therein new moral notions. Stoicism insists upon the self-sufficiency of virtue quite as strongly as Cynicism, and will allow quite as little that anything except virtue can be a good in the strictest sense of the term. But in Stoicism the individual is not nearly so sharply opposed to the outer world as in Cynicism. The Stoic is too cultivated; he knows too well that he is a part of the universe to ignore the value of an intellectual view of the world, or to neglect the natural conditions of moral action, as things of no moment. What he aims at is not only a negation—independence from externals—but a positive position—life according to nature; and that life only he considers according to nature which is in harmony with the laws of the universe as well as with those of human nature. Hence Stoicism is not only far in advance of Cynicism by its intellectual attitude, but its moral philosophy also breathes a freer and milder spirit. Let only the principles of the Stoics on the necessity and value of scientific knowledge be compared with the sophistical assertions of Antisthenes, destructive of all knowledge; or the cultivated logical form of the intellectual edifice of the Stoics, with the chaotic condition of Cynic thought; or the careful metaphysical and psychological researches and the copious learning of the School of Chrysippus, with the Cynics’ contempt for all theory and all learned research, and it becomes apparent at once how deep-seated is the difference between the two systems, and how little Stoicism as a philosophic system can be deduced from Cynicism.