b. Fire is the Cosmic Substance. Here we come to a difficulty in explaining the doctrine of Heracleitus because of the confusion in his own mind. He evidently goes a long way toward conceiving the cosmic substance as an abstraction—as the process of change. But he could not be wholly abstract. He stops and tells us that the cosmic substance is fire, and he probably means by fire just the same sort of thing as Anaximenes meant by air. Fire is the cosmic substance. It is the essence of all material things because it is the most mobile. But, after all, the fire of which Heracleitus is thinking is not a localized thing, like the fire on the hearth. For the hearth fire in a sense is ever identical with itself. The fire which Heracleitus means is ever darting, ever transforming material. To sum up: Heracleitus does not mean by fire an abstraction like the law of change; he does not mean, on the other hand, a material ever remaining like itself: he does mean a material, but a transforming material.
c. The Definite Changes of Fire. Heracleitus makes some acute observations about the characteristics of the changing fire. The Milesians had been content to observe atmospheric changes and to name condensation and rarefaction as the forms of cosmic change. Heracleitus goes farther and emphasizes definite relations of change. The succession of changes always remains the same. Their definite relation is the only permanence in the world, and Heracleitus’ conception foreshadows the modern conception of the uniformity of the law of nature. The changes are (1) fateful, (2) rational, and (3) just. They show that the world is a destiny, a reason, and a justice. This identification of ethical and logical qualities with the physical betrays the undeveloped condition of the thought of Heracleitus.
In general, there are two characteristics to be noted with reference to Heracleitus’ conception of a definite succession of changes: (1) the changes are always a harmony of opposites; (2) and the changes are in a closed circuit. The process of change is not a flow in one direction like a river over its bed, but it is a movement in two opposite directions. By change Heracleitus means not only a passing into something else but a passing into the opposite. Everything is the union of opposites, and everything is the transition point of opposites about to separate. The flux of things is thus poetically conceived as a war of things, and this war is “the father of all things.” This unity of opposites has an equilibrium that illudes us into thinking it is permanent. The universe is an invisible harmony, divided into itself and again united. Investigate life and there are antitheses everywhere. War is life. The second general characteristic of the succession of changes istheir closed circuit. Fire changes into all things, and all things are changing back into fire. These two movements are called the “Upward Way” and the “Downward Way.” Downward, fire changes through air and water into earth. Upward, earth changes back to water, air, and fire. With every change, there is counter-change, action is accompanied by a reaction. “Men do not know how that which is drawn in opposite directions harmonizes with itself. The harmonious structure of the world depends upon opposite tension, like that of the bow and the lyre.”
d. The Practical Philosophy of Heracleitus. Heracleitus was more of a metaphysician than a physicist, and his chief concern was in the formation and the practical application of his theory of change. He looked upon man as a bit of cosmic fire struck off and imprisoned in a body of earth, water, and air. After death this fiery soul is released and absorbed in the cosmic fire. In his present state man has a divided existence: the life of the soul, or the fire of the reason; and the life of the senses of the imprisoning body. The reason retires from the illusions of sense, and sees in its aristocratic isolation how illusory the sensations are. For the senses tell us that their objects are permanent, while the reason sees through this deception to the changingness of the world. Thus the beginning is made by Heracleitus in distinguishing the reflections of the reason from sensations. Truth is for the first time systematically set over against opinion. The reasonable Wise Man resigns himself to whatever happens because he knows that it is fateful, wise, and just. The Wise Man recognizes that all is change, and he is happy because he sees providence in the vicissitudes of his ownlife. Thus in the aristocratic hate, which Heracleitus holds against democracies, he makes conformity to law the only way to happiness. The reason of Wise Men, and not the senses of the multitude, must be the true guide of society.
Heracleitus was a profound observer and theorist. His physical theory foreshadowed the modern theories of natural law and of relativity; his practical theories reappear in the psychology of Protagoras and the ethics of the Stoics.
4. The Eleatic School. The town of Elea to which Xenophanes came in the course of his wanderings had been recently settled by the Ionian refugees from Phocæa, a great maritime city in Asia Minor, which had been conquered by the Persians (543 B. C.). Elea is now Castellamare on the west coast of Italy. It is celebrated as the birthplace of Parmenides and Zeno, who founded the so-called Eleatic school.
a. Parmenides (b. 515 B. C.).
Parmenides wrote about 470 B. C. He is represented as a serious and influential man, with a high moral character. He exercised strong influence upon such philosophers as Plato and Democritus, and was a political power in the city of Elea, of which he was a native. He was not a stranger to the Pythagoreans. The large fragment of his poem is the most ancient monument extant of metaphysical speculation among the Greeks.
Parmenides takes the doctrine of Xenophanes with great seriousness, and what Xenophanes says about the Godhead, Parmenides says about all things. Xenophanes’ religious weapon of an unchanging cosmic substance becomes in the hands of Parmenides an academic doctrine of science and the basis of logical controversy.Parmenides used the conception of Xenophanes in his great didactic poem, The Way of Truth and the Way of Opinion, with the evident purpose of refuting the theory of Heracleitus. The fragment of the poem reveals the driest abstractions dressed in rich poetry. As a thinker Parmenides is the most important in this period. Zeno was the friend and pupil of Parmenides.
(1) The Cosmic Substance is Being. The first assumption in the Milesian doctrine—that there is a single matter that ever remains identical with itself—was so self-evident to Parmenides that he does not attempt to prove it. He assumes it, as if it were cogent to everybody. However, he explains what he means by Being in a negative statement: Not-Being, or what is not, cannot be thought. Being and thought are so correlated that they are the same. Thinking always has Being as its content, and there is no Being that is not thought. Being ＝ Thought. This explanation of Parmenides’ identification of thought and Being may be put in this logical form:—