Asking in the next place in how far the Stoics were induced by other influences to change and extend the platform of the Socratic philosophy, we have for determining the practical side of their system, besides the general tendency of the post-Aristotelian [(2) Relation to Megarians and Heraclitus.] philosophy, the example of Cynicism. Its speculative development, on the other hand, is partly connected with the Megarians, partly with Heraclitus; to the Megarians the personal connection of Zeno with Stilpo points, to Heraclitus the fact that from him the Stoics themselves deduced their views on natural science, which they expanded in commentaries on his writings. [1039] [(a) The Megarians.] Probably the Megarian influence must not be rated too high. Zeno may have thence received an impulse to that reasoning habit which appears with him in a preference for compressed sharp-pointed syllogisms; [1040] but in post-Aristotelian times, contact with Megarians was no longer wanted for this, and the greatest reasoner among the Stoics, Chrysippus, appears not only to have had no personal relations to them, but his logic is throughout a simple continuation of that of Aristotle. [(b) Heraclitus.] Far greater, and more generally recognised, is the importance of the influence which the views on nature of the philosopher of Ephesus exercised on the Stoics. A system which laid such emphasis on the subordination of everything individual to the law of the universe, which singled out universal reason from the flux of things as the one thing everlastingly and permanently the same—a system in many other ways so nearly related to their own, must have strongly commended itself to their notice, and offered them many points with which to connect their own. If to us the view that life is dependent for its existence on matter is repulsive, it was otherwise to the Stoics; for them this very theory possessed special attractions. Hence, with the exception of the threefold division of the elements, there is hardly a single point in the Heraclitean theory of nature which the Stoics did not appropriate:—fire or ether as the primary element, the oneness of this element with universal reason, the law of the universe, destiny, God, the flux of things, the gradual change of the primary element into the four elements, and of these back to the primary element, the regular alternation of creation and conflagration in the world, the oneness and eternity of the universe, the description of the soul as fiery breath, the identification of the mind with the demon, the unconditional sovereignty of the universal law over individuals—these and many other points in the Stoic system, originally derived from Heraclitus, [1041] prove how greatly this system is indebted to him.