As with Empedocles and the Atomists, a moving force is required to explain the world-process of unmixing. What, in the philosophy of Anaxagoras, is this force? Now up to the present point the philosophy of Anaxagoras does not rise above the previous philosophies of Empedocles and the Atomists. On the contrary, in clearness and logical consistency, it falls considerably below the teaching of the latter. But it is just here, on the question of the moving force, that Anaxagoras becomes for the first time wholly original, and introduces a principle peculiar to himself, a principle, moreover, which is entirely new in philosophy. Empedocles had taken as his moving forces, Love and Hate, mythical and fanciful on the one hand, and yet purely physical on the other. The forces of the Atomists were also completely material. But Anaxagoras conceives the moving force as wholly non-physical and incorporeal.
Anaxagoras introduced the idea of a force called mind. It is called the Nous, that is, mind or intelligence. It is intelligence which produces the movement in things which brings about the formation of the world. What was it, now, which led Anaxagoras to the doctrine of a world-governing intelligence? It seems that he was struck with the apparent design, order, beauty and harmony of the universe. These things, he thought, could not be accounted for by blind forces. The world is apparently a rationally governed world.
It moves towards definite ends. Nature shows plentiful examples of the adaptation of means to ends. There appears to be plan and purpose in the world. The Atomists had assumed nothing but matter and physical force. How can design, order, harmony and beauty be brought about by blind forces acting upon chaotic matter? Blind forces acting upon a chaos would produce motion and change. But the change would be meaningless and purposeless. They could not produce a rationally ordered cosmos. One chaos would succeed another chaos ad infinitum. That alone which can produce law and order is intelligence. There must therefore be a world-controlling Nous.
What is the character of the Nous, according to Anaxagoras? Is it, in the first place, really conceived as purely non-material and incorporeal? Aristotle, who was in a position to know more of the matter than any modern scholar, clearly implies in his criticism that the Nous of Anaxagoras is an incorporeal principle, and he has been followed in this by the majority of the best modern writers, such as Zeller and Erdmann. But the opposite view has been maintained, by Grote, for example, and more recently by Professor Burnet, who thinks that Anaxagoras conceived the Nous as a material and physical force.
As the matter is of fundamental importance, I will mention the chief arguments upon which Professor Burnet rests his case. In the first place Anaxagoras definition the Nous as the “thinnest and purest of all things.” He also said that it was “unmixed,” that it had in it no mixture of anything besides itself. Professor Burnet argues that such words as “thin” and “unmixed” would be meaningless in connection with an incorporeal principle. Only material things can properly be described as thin, pure, and unmixed. Secondly, Professor Burnet thinks that it is quite certain that the Nous occupies space, for Anaxagoras speaks of greater and smaller portions of it. Greater and smaller are spatial relations. Hence the Nous occupies space, and that which occupies space is material. But surely these are very inconclusive arguments.
In the first place as regards the use of the words “thin” and “unmixed.” It is true that these terms express primarily physical qualities. But, as I pointed out in the first chapter, almost all words by which we seek to express incorporeal ideas have originally a physical signification. And if Anaxagoras is to be called a materialist because he described the Nous as thin, then we must also plead guilty to materialism if we say that the thought of Plato is “luminous,” or that the mind of Aristotle is “clear.” The fact is that all philosophy labours under the difficulty of having to express non-sensuous thought in language which has been evolved for the purpose of expressing sensuous ideas. There is no philosophy in the world, even up to the present day, in which expressions could not be found in plenty which are based upon non-physical ideas.
Then as regards the Nous occupying space, it is not true that greater and smaller are necessarily spatial relations. They are also qualitative relations of degree. I say that the mind of Plato is greater than the mind of Callias. Am I to be called a materialist? Am I to be supposed to mean that Plato’s mind occupies more space than that of Callias? And it is certainly in this way that Anaxagoras uses the terms. “All Nous,” he says, “is alike, both the greater and the smaller.” He means thereby that the world-forming mind (the greater) is identical in character with the mind of man (the smaller). For Anaxagoras it is the one Nous which animates all living beings, men, animals, and even plants. These different orders of beings are animated by the same Nous but in different degrees, that of man being the greatest. But this does not mean that the Nous in man occupies more space than the Nous in a plant.
But even if Anaxagoras did conceive the Nous as spatial, it does not follow that he regarded it as material. The doctrine of the non-spatiality of mind is a modern doctrine, never fully developed till the time of Descartes. And to say that Anaxagoras did not realize that mind is non-spatial is merely to say that he lived before the time of Descartes.
No doubt it would follow from this that the incorporeality of mind is vaguely and indistinctly conceived by Anaxagoras, that the antithesis between matter and mind is not so sharply drawn by him as it is by us. But still the antithesis is conceived, and therefore it is correct to say that the Nous of Anaxagoras is an incorporeal principle. The whole point of this introduction of the Nous into the philosophy of Anaxagoras is because he could not explain the design and order of the universe on a purely physical basis.
The next characteristic of Nous is that it is to be thought of as essentially the ground of motion. It is because he cannot in any other way explain purposive motion that Anaxagoras introduces mind into his otherwise materialistic system.
Mind plays the part of the moving force which explains the world-process of unmixing. As the ground of motion, the Nous is itself unmoved; for if there were any motion in it we should have to seek for the ground of this motion in something else outside it. That which is the cause of all motion, cannot itself be moved. Next, the Nous is absolutely pure and unmixed with anything else.
It exists apart, by itself, wholly in itself, and for itself. In contrast to matter, it is uncompounded and simple. It is this which gives it omnipotence, complete power over everything, because there is no mixture of matter in it to limit it, to clog and hinder its activities. We moderns are inclined to ask the question whether the Nous is personal. Is it, for example, a personal being like the God of the Christians? This is a question which it is almost impossible to answer.
Anaxagoras certainly never considered it. According to Zeller, the Greeks had an imperfect and undeveloped conception of personality. Even in Plato we find the same difficulty. The antithesis between God as a personal and as an impersonal being, is a wholly modern idea. No Greek ever discussed it.
To come now to the question of the activity of the Nous and its function in the philosophy of Anaxagoras, we must note that it is essentially a world-forming, and not a world creating, intelligence. The Nous and matter exist side by side from eternity. It does not create matter, but only arranges it. “All things were together,” says Anaxagoras, “infinitely numerous, infinitely little; then came the Nous and set them in order.” In this Anaxagoras showed a sound logical sense. He based his idea of the existence of Nous upon the design which exhibits itself in the world. In modern times the existence of design in the world has been made the foundation of an argument for the existence of God, which is known as the teleological argument.
The word teleology means the view of things as adapting means towards purposive ends. To see intelligent design in the universe is to view the universe teleologically. And the teleological argument for the existence of God asserts that, as there is evidence of purpose in nature, this must be due to an intelligent cause. But, as a matter of fact, taken by itself, teleology cannot possibly be made the basis of an argument for the existence of a world-creating intelligence, but only for the existence of a world-designing intelligence.
If you find in the desert the ruins of ancient cities and temples, you are entitled to conclude therefrom, that there existed a mind which designed these cities and buildings, and which arranged matter in that purposive way, but you are not entitled to conclude that the mind which designed the cities also created the matter out of which they were made. Anaxagoras was, therefore, in that sense quite right. Teleology is not evidence of a world-creating mind, and if we are to prove that, we must have recourse to other lines of reasoning.
In the beginning, then, there was a chaotic mixture of different kinds of matter. The Nous produced a vortex at one point in the middle of this mass. This vortex spread itself outwards in the mass of matter, like rings caused by the fall of a stone in water. It goes on for ever and continually draws more and more matter out of the infinite mass into itself. The movement, therefore, is never-ending.
It causes like kinds of matter to come together with like, gold to gold, wood to wood, water to water, and so on. It is to be noted, therefore, that the action of the Nous is apparently confined to the first movement. It acts only at the one central point, and every subsequent movement is caused by the vortex itself, which draws in more and more of the surrounding matter into itself. First are separated out the warm, dry, and light particles, and these form the aether or upper air.
Anaxagoras discoveries
Next come the cold, moist, dark, and dense particles which form the lower air. Rotation takes the latter towards the centre, and out of this the earth is formed. The earth, as with Anaximenes, is a flat disc, borne upon the air. The heavenly bodies consist of masses of stone which have been torn from the earth by the force of its rotation, and being projected outwards become incandescent through the rapidity of their movement. The moon is made of earth and reflects the light of the sun.
Anaxagoras was thus the first to give the true cause of the moon’s light. He was also the first to discover the true theory of eclipses, since he taught that the solar eclipse is due to the intervention of the moon between the sun and the earth, and that lunar eclipses arise from the shadow of the earth falling upon the moon. He believed that there are other worlds besides our own with their own suns and moons. These worlds are inhabited. The sun, according to Anaxagoras, is many times as large as the Peloponnese.
The origin of life upon the earth is accounted for by germs which existed in the atmosphere, and which were brought down into the terrestrial slime by rain water, and there fructified. Anaxagoras’s theory of perception is the opposite of the theories of Empedocles and the Atomists. Perception takes place by unlike matter meeting unlike.
The Nous -Anaxagoras owes his importance in the history of philosophy to the theory of the Nous. This was the first time that a definite distinction had been made between the corporeal and incorporeal. Anaxagoras is the last philosopher of the first period of Greek philosophy. In the second chapter, I observed that this first period is characterized by the fact that in it the Greek mind looks only outward upon the external world. It attempts to explain the operations of nature. It had not yet learned to look inward upon itself. But the transition to the introspective study of mind is found in the Nous of Anaxagoras. Mind is now brought to the fore as a problem for philosophy. To find reason, intelligence, mind, in all things, in the State, in the individual, in external nature, this is the characteristic of the second period of Greek philosophy. To have formulated the antithesis between mind and matter is the most important work of Anaxagoras.
Anaxagoras' theory Atomists
Secondly, it is to the credit of Anaxagoras that he was the first to introduce the idea of teleology into philosophy. The system of the Atomists formed the logical completion of the mechanical theory of the world. The theory of mechanism seeks to explain all things by causes. But, as we saw, causation can explain nothing. The mechanism of the world shows us by what means events are brought about, but it does not explain why they are brought about at all. That can only be explained by showing the reason for things, by exhibiting all process as a means towards rational ends.
To look to the beginning (cause) of things for their explanation is the theory of mechanism. To look to their ends for explanation of them is teleology. Anaxagoras was the first to have dimly seen this. And for this reason Aristotle praises him, and, contrasting him with the mechanists, Leucippus and Democritus, says that he appears like “a sober man among vain babblers.” The new principle which he thus introduced into philosophy was developed, and formed the central idea of Plato and Aristotle. To have realized the twin antitheses of matter and mind, of mechanism and teleology, is the glory of Anaxagoras.
But it is just here, in the development of these two ideas, that the defects of his system make their appearance. Firstly, he so separated matter and mind that his philosophy ends in sheer dualism. He assumes the Nous and matter as existing from the beginning, side by side, as equally ultimate and underived principles. A monistic materialism would have derived the Nous from matter, and a monistic idealism would have derived matter from the Nous. But Anaxagoras does neither. Each is left, in his theory, an inexplicable ultimate mystery. His philosophy is, therefore, an irreconcilable dualism. Secondly, his teleology turns out in the end to be only a new theory of mechanism.
The only reason which induces him to introduce the Nous into the world, is because he can not otherwise explain the origin of movement. It is only the first movement of things, the formation of the vortex, which he explains by mind. All subsequent process is explained by the action of the vortex itself, which draws the surrounding matter into itself. The Nous is thus nothing but another piece of mechanism to account for the first impulse to motion. He regards the Nous simply as a first cause, and thus the characteristic of all mechanism, to look back to first causes, to the beginning, rather than to the end of things for their explanation, appears here. Aristotle, as usual, puts the matter in a nutshell. “Anaxagoras,” he says, “uses mind as a deus ex machina to account for the formation of the world, and whenever he is at a loss to explain why anything necessarily is, he drags it in by force. But in other cases he assigns as a cause for things anything else in preference to mind.”
Anaxagoras quotes
“And since the portions of both the large and the small are equal in amount, in this way too all things would be in everything; nor can they be separate, but all things have a portion of everything. Since there cannot be a smallest, nothing can be separated or come to be by itself, but as in the beginning now too all things are together. But in all things there are many things, equal in amount, both in the larger and the smaller of the things being separated off.”
Anaxagoras said is our universe the only universe
“Mind is god and god is Mind”
“Appearances are a glimpse of the unseen.”
“Men would live exceedingly quiet if these two words, mine and thine, were taken away.”
“Everything has a natural explanation. The moon is not a god but a great rock and the sun a hot rock.”
“The Greeks do not think correctly about coming-to-be and passing-away; for no thing comes to be or passes away, but is mixed together and dissociated from the things that are. And thus they would be correct to call coming-to-be mixing-together and passing-away dissociating”
Anaxagoras trial
The citizens of Athens, like those of other cities in other ages and continents, showed a certain hostility to those who attempted to introduce a higher level of culture than that to which they were accustomed. When Pericles was growing old, his opponents began a campaign against him by attacking his friends. They accused Pheidias of embezzling some of the gold that was to be employed on his statues. They passed a law permitting impeachment of those who did not practise religion and taught theories about "the things on high." Under this law, they prosecuted Anaxagoras, who was accused of teaching that the sun was a red-hot stone and the moon was earth.
(The same accusation was repeated by the prosecutors of Socrates, who made fun of them for being out of date.) What happened is not certain, except that he had to leave Athens. It seems probable that Pericles got him out of prison and managed to get him away. He returned to Ionia, where he founded a school. In accordance with his will, the anniversary of his death was kept as a school childrens' holiday.
Anaxagoras philosophy summary
Anaxagoras is an interesting case-study in the Pre-socratic moment of philosophy, because in his theory the combination of a priori reasoning and inductions from observation, typical enough not just of philosophy’s beginnings but of its entire history, manifests itself in clear outline. What he says about the source of river water, eclipses of the moon and some of the phenomena of sensory perception interestingly anticipates not just later views but the possibility of empirical verification of them.