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Greek and Greco-Roman Philosophy · Glenn · History of Philosophy · 1929

The Earlier Ionian School

Thales, Anaximander, and Anaximenes: the search for a single material principle of all things; the beginning of natural philosophy in Miletus.

book_5 Before you read

The Milesian natural philosophers — Thales (fl. 585 BC), Anaximander (610–547 BC), and Anaximenes (fl. 550 BC) — initiated Western philosophy by asking: what is the one underlying substance (arche) of which all things are made? Thales answered: water. Anaximander: the apeiron (the indeterminate or boundless) — an infinite, undifferentiated substrate from which all definite things emerge and into which they return. Anaximenes: air. Their genius was not in their specific answers, which are too simple, but in the boldness of their question and the method of their inquiry: they replaced mythological explanation with the search for a rational natural principle accessible to human reason. Their approach is limited by materialism and by a merely cosmological concept of the divine, but historically their work is the absolutely decisive transition from myth to philosophy.

Article i. The Earlier Ionian School

a) Thales; b) Anaximander; c) Anaximenes. Ionia, first and most important of the Greek colonies, was situated in Asia Minor on the shores and islands which look westward towards the Grecian peninsula across the Ægean Sea. The most notable city of Ionia was Miletus, birthplace of all three philosophers here discussed. The problem investigated by the Earlier Ionians was that presented by the material universe. They inquired, “What, in the last analysis, is the world made of?” They saw a world around them which evidently remained the same world, and yet was full of change, motion, and of variety. There were 36 dawns and sunsets, births and deaths, storms and calms, running streams and enduring mountains, moving planets, the solid earth, and the ever restless sea. There were various kinds of things in the world—minerals, plants, brutes, men. Now the Ionians felt that, back of all changes and varieties in the world, there must be some one thing which is the fundamental material out of which all things are made—some “worldstuff,” of which different things are the variants and manifestations. The Earlier Ionians tried to answer the question, “What is the world-stuff?”

a) Thal es (about 624-545 b. c.)

Life: Thales was born at Miletus. He was a mathematician and an astronomer. He also showed ability as a man of business, a military engineer, and a philosopher. He was one of “The Seven Wise Men of Greece.” What we know of him is traditional history which was consigned to writing long after his time and was recounted by Aristotle in the 4 century b. c.

Works: It is probable that Thales wrote nothing. At any rate, no writing of his survives.

Doctrine: The world-stuff is water. All things are made of water. The world emerges from water, returns again to water, and repeats this process continually at stated periods (infinite series of worlds). Water is infinite and alive. Hence the whole universe lives (hylozoism). Aristotle gives some intèresting conjectures upon the probable reasons that led Thales to his belief. There are two points in this doctrine : first, all things are of the same basic nature ; and, secondly, this basic nature is that of water. That all things are of the same basic nature is suggested by the fact that the earth nourishes plants, plants nourish animals, brute animals nourish men; therefore men, brutes, plants, and earth must possess a common fundamental element, a common basic nature. This nature is that of water, for water alone can assume the conditions of solid (ice), liquid, and gas (mist or vapor) ; and all things in the world are solid, liquid, or gaseous. That water (and hence the universe) is alive, is suggested by the fact that moisture supports life. Living things are always moist; plants require moist soil; animals and men require moisture to make food digestible. When things lose moisture we say that they die—and yet all things live, for moisture is never absent from them. Even the driest land contains moisture, as one may discover by digging into it. Fire itself, though seemingly the farthest thing removed from moisture, requires it, and we see the sun drawing up moisture from the sea. Thales is said to have taught that the earth floats on water like a leaf upon the surface of a pool. When the pool is disturbed we have earthquakes. If one be disposed to doubt that all things live, let him be convinced by considering the lodestone (magnet), which is seemingly the most inert and lifeless of things, but shows its life-force by its action in attracting particles of iron.

Remarks: The idea that the world emerged from a chaos of waters was common among all ancient Oriental peoples, but Thales extended it so as to include not only the world’s origin but also its material structure. The only point certainly taught by Thales is that the worldstuff is water. The reasons given above which may have led him to this view are traditional, but they are only conjectures, and we have no certainty that Thales himself offered them or even that he was aware of them. Thales’ service to philosophy was not that he answered the question, “What is the world-stuff?” but that he asked the question. Thus he drew the attention of thinkers to a most important matter. That branch of philosophy which studies the nature and causes of the material world is called Cosmology; and the fact that Thales raised the cosmological inquiry entitles him to the name which history has bestowed upon him—“The Father of Cosmology.”

b) Anaximander (about 611-547 b. c.)

Life: Anaximander was born at Miletus. It is probable that he was a pupil of Thales. He was a student of physics, astronomy, and geography.

Works: Anaximander wrote a treatise “On Nature” of which only two sentences survive. What we know of his doctrine is taken from the works of Theophrastus and Aristotle (both 4 century b. c.).

Doctrine: The world-stuff is an infinite, living, material substance called “The Boundless.” This infinite substance is to be conceived as a sort of spray or mist which in the beginning contained particles of every kind of body found in the world, and elements of heat and cold, wet and dry. Bodily things were separated out from the Boundless by the action of its heat elements. Through the action of heat the warmer particles drew off from the colder, and both were condensed. The condensed warm elements took shape as the sun and the heavenly bodies, while the cold elements condensed into the earth and its waters. The sun beat upon the earth, gradually drying it and causing the waters to run off the surface of the land to form the ocean which surrounds the earth. Continued action of heat upon the drying earth raised bubbles upon its muddy surface, and presently these broke from their moorings and became fishes. The fishes evolved into animals and ultimately into men. The earth is a cylinder poised in the centre of the universe. The sun and other bright heavenly bodies are great rings of fire which surround the earth, and what we see of them is but apertures in the rings. When these apertures are wholly or partially stopped up, we have eclipses. The world will eventually be reduced to the spray-form of the primal Boundless, and then it will emerge as before, and this process will go on repeating itself indefinitely (infinite series of worlds).

Remark: Anaximander’s doctrine had a powerful influence upon the current of subsequent thought. We may be astonished to find that the theory of material evolution is so very old. But, after all, evolution is an almost childish explanation of the universe, and it could scarcely fail to suggest itself to an untaught mind trying to account for the wonderful world of things as they are.

c) Anaximenes (about 588-524 b. c.)

Life: Anaximenes was born at Miletus. He is said to have been a pupil of Anaximander.

Works: Anaximenes wrote a scientific treatise on the nature of the world, but of this work only one sentence remains and it is not of certain genuinity. What we know of this philosopher is taken from Theophrastus (4 century b. c.).

Doctrine: The world-stuff is air or vapor. This vapor is an infinite, living mass. It is marked by a thickening and thinning process (condensation and rarefaction) which causes different things—winds, clouds, water, fire, earth—to emerge. The earth and the heavenly bodies float in the boundless air like leaves. Anaximenes probably held the infinite series of worlds theory.

Remark: Anaximenes owes much to his two predecessors in the School of Earlier Ionians. From Thales he took the notion of a single world-stuff, and from Anaximander he took the idea of a process of “separating out” the bodily universe from the original boundless mass of air.

Remarks on the Earlier Ionians.— These philosophers tried to unify their knowledge of the world with its bewildering variety and multiplicity. They took the most direct way to their end by unifying all things in a common structural source. But they did not teach that different things in the world remain the same in their intrinsic constitution after being separated out from the primal world-stuff. Had they taught this, they would have been monists; but, as a matter of fact, they were pluralists, and taught that things in the world have their proper individuality and their essentially different qualities in spite of a common origin and destiny. They believed that the world-stuff and the welter of things separated out from it are alive (hylozoism), and that the world-stuff has its own power of developing into different things (dynamism). They tried to give an account of the nature of the world (cosmology), and did not merely describe the origin or actual emergence of the world (cosmogony). The service of the Earlier Ionians to philosophy lies in the fact that they presented the world-problem to the minds of men.