ANAXAGORAS, Greek philosopher, born probably about 500 B.C. (Apollodorus ap. Diog. Laert. ii. 7) at Clazomenae in Asia Minor. He went to Athens, which was rapidly becoming the headquarters of Greek culture (c. 464-462 B.c.). There he is said to I Ave remained for 3o years. Pericles learned to love and ad mire him and the poet Euripides derived from him an enthusi asm for science and humanity. Some authorities assert that even Socrates was among his disciples. His influence was due partly to his astronomical and mathematical eminence, but still more to the ascetic dignity of his nature and his superiority to ordinary weaknesses.
It was he who brought philosophy and the spirit of scientific inquiry from Ionia to Athens. His observations of the celestial bodies led him to form new theories of the universal order, and brought him into collision with the popular faith. He attempted to give a scientific account of eclipses, meteors, rainbows and the sun, which he described as a mass of blazing metal, larger than the Peloponnesus; the heavenly bodies, he said, were masses of stone torn from the earth and ignited by rapid rotation. The polytheism of the time could not tolerate such explanation, and the enemies of Pericles used the superstitions of their countrymen as a means of attacking him in the person of his friend.
Anaxagoras was arrested on a charge of contravening the estab lished dogmas of religion (some say the charge was one of Medism) and it required all the eloquence of Pericles to secure his acquittal. Even so he was forced to retire from Athens to Lampsacus B.c.), where he died about 428 B.C. Anax agoras holds that all things have existed in a sort of way from the beginning. But originally they existed in infinitesimally small fragments of themselves, endless in number and inextricably com bined throughout the universe.
All things existed in this mass, but in an indistinguishable form. There were the seeds of corn and flesh and gold in the mixture; but these parts, of like nature with their wholes (the omocomepi of Aristotle), had to be eliminated from the complex mass before they could receive a definite name and character.
The existing species of things having thus been transferred, with all their specialties, to the prehistoric stage, they were multiplied endlessly in number by reducing their size through continued sub division; at the same time each thing is so connected with every other that the keenest analysis can never completely sever them. The work of arrangement, the segregation of like from unlike and the summation of the oµotoµ€pij ("simple substances") into totals of the same name, was the work of Mind or Reason. This peculiar thing called Mind (vows), was no less illimitable than the chaotic mass, but, unlike the Intelligence of Heraclitus (q.v.), it stood pure and independent (µovvos E•' Ecovrov), a thing of finer texture, and everywhere the same.
This agent, possessed of all knowledge and power, is especially seen ruling in all the forms of life. Its first appearance, and the only manifestation of it which Anaxagoras describes, is Motion. It originated a rotatory movement in the mass which, arising at one point, gradually extended till it gave distinctness to the aggre gates of like parts. But even after it has done its best, the original intermixture is not wholly overcome. No one thing in the world is ever abruptly separated from the rest. The name given to it signifies merely that in that congeries of fragments the particular "seed" is preponderant. Every a of this present universe is only a by a majority, and is also in lesser number b, c, d. It is note worthy that Aristotle accuses Anaxagoras of failing to differenti ate between vows andvxr} while Socrates (Plato, Phaedo, 98 B) objects that his vows is merely a dens ex machina to which he refuses to attribute design and knowledge.
Anaxagoras gave some account of the process from original chaos to present arrangements. First came the division into cold mist and warm ether. With increasing cold, the former gave rise to water, earth and stones. The seeds of life in the air were carried down with the rains and produced vegetation. Animals, including man, sprang from the warm and moist clay. We seem to see things coming into being and passing from it ; but reflection tells us that decease and growth only mean a new aggregation (airpcptcrts) and disruption Thus Anaxagoras dis trusted the senses, and preferred the conclusions of reflection. Accordingly, he maintained that there must be blackness as well as whiteness in snow ; how otherwise could it be turned into dark water? With Anaxagoras speculation passed from the colonies of Greece to settle at Athens. His theory of minute constituents and mechanical processes 'paved the way for the atomic theory. On the other hand the conception of reason in the world passed from him to Aristotle, to whom it seemed the dawn of sober thought after a night of disordered dreams. From Aristotle it descended to his commentators, and under the influence of Averroes became the engrossing topic of speculation.
fragments of Anaxagoras have been collected by E. Schaubach (Leipzig, 1827), and W. Schorn (Bonn, 1829) ; see also F. W. A. Mullach, Fragmenta Philos. Graec., i. 243-252 ; A. Fair banks, The First Philosophers of Greece (1898) . For criticism see T. Gomperz, Greek Thinkers (Eng. trans., L. Magnus, i901), bk. ii. chap. 4 ; E. Bersot, De controversis quibusdam Anaxagorae doctrinis (1844) ; E. Zeller, Die Philosophie der Griechen (Eng. trans., S. F. Alleyne, London, 1881) ; J. M. Robertson, Short History of Free thought (1906) ; W. Windelband, History of Philosophy (Eng. trans., J. H. Tufts, 1893) ; J. I. Beare, Greek Theories of Elementary Cogni tion (1906) ; L. Parmentier, Euripide et Anaxagore (1892) ; F. Lortzing, "Bericht fiber die griechischen Philosophen vor Sokrates" (for the years 1876-97), in Bursian's Jahresbericht fiber die Fortschritte der classischen Altertumswissenschaft, cxvi. (1904) with references to im portant articles in periodicals.
On the date of the trial of Anaxagoras see Burnet, Early Greek Philosophy, ch. vi. (1908) ; A. E. Taylor, Classical Quarterly, xi. 1917.