Anaxagoras

« Anaxagoras (500-428 BC) Anaxagoras of Clazomenae was a major Greek philosopher of the Presocratic period, who worked in the Ionian tradition of inquiry into nature.

While his cosmology largely recasts the sixth-century system of Anaximenes, the focus of the surviving fragments is on ontological questions.

The often quoted opening of his book - 'all things were together' - echoes the Eleatic Parmenides' characterization of true being, but signals recognition of time, change and plurality.

Even so, Anaxagoras is deeply committed to the Eleatic notions that, strictly speaking, there can be no coming into being or going out of existence, nor any separation of one part of reality from any other.

His main object is to show how the variety of the world about us is somehow already contained in the primordial mixture, and is explicable only on the assumption that latent within each substance are portions of every other.

Whether or not he owed his conception of unlimited smallness to Zeno of Elea, he held that there could be no such thing as a magnitude of least size; and he claimed that there was accordingly no difference in complexity between the large and the small.

Mind, however, is a distinct principle; unlimited, autonomous, free from the admixture of any other substance.

Hence Anaxagoras' decision to make it the first cause of the ordered universe we now inhabit.

Mind initiates and controls a vortex, which from small beginnings sucks in an ever-increasing expanse of the surrounding envelope.

The vortex brings about an incomplete separation of the ingredients of the original mixture: hot from cold, dry from wet, bright from dark, and so on, with a flat earth compacted at the centre and surrounded by misty air and clearer ether above and below. Contemporaries were scandalized by Anaxagoras' claim that sun, moon and stars were nothing but incandescent stones caught up in the revolving ether.

Later fifth-century physicists - notably Archelaus and Diogenes of Apollonia - developed revised versions of Anaxagoras' system, but abandoned his dualism.

His conception of mind excited but disappointed Socrates, and exercised a profound influence on Plato's cosmology and Aristotle's psychology.

Aristotle was also fascinated by the complexities of the remarkable theory of 'everything in everything'.

Anaxagoras' philosophy was never subsequently revived, but he was remembered as the mentor of the statesman Pericles and the poet Euripides.

His reputation as a rationalist critic of religion persisted throughout antiquity.

1 Life and work Anaxagoras, son of Hegesibulus, was a native of Clazomenae (a coastal town in what is now Turkey).

He was the first major philosopher to spend time in Athens, where he was an associate of the statesman Pericles.

The evidence for his residence there is confused although quite extensive.

He is said to have arrived in Athens in the archonship of Callias (456/5 BC).

Knowledge of his ideas probably preceded his arrival, to judge from echoes of his explanation of physical phenomena in Aeschylus' tragedies Supplices (c.463 BC) and Eumenides (458 BC).

He was believed to have predicted the fall of a large meteorite in Thrace that is dated c.467 BC.

Anaxagoras' stay in Athens may have lasted for about twenty years (so Mansfeld 1979-80), until his prosecution and trial on a charge of impiety (dated by Mansfeld to 437/6 BC).

He died in Lampsacus on the Hellespont, where the funeral honours accorded to him suggest a high reputation.

Diogenes Laertius (I 16) counts Anaxagoras among those philosophers who wrote only one work.

But some of his views, for example those on perspective and geometry, may have been the subjects of separate memoranda (A38-40).

The surviving fragments all appear to come from a general work on the nature and origins of the physical world.

The fact of their survival makes for a more direct impression of Anaxagoras' style of thought and his major theses than is possible in the case of Presocratics such as Anaximenes.

However, there remain considerable problems of interpretation.

One reason is that Anaxagoras' prose, while capable of striking and elevated effect, is too dense and imprecise to allow determinate formulation of the subtle and ingenious distinctions which scholarship has seen as fundamental to his system.

Another is that the Aristotelian commentator Simplicius, who is responsible for preserving most of the fragments, quotes them not in the course of a straightforward exposition of Anaxagoras' philosophy, but in order to illustrate various points in either Aristotle's account of Anaxagorean ontology or his own Neoplatonist interpretation of the cosmogony.

So while possession of actual extracts from Anaxagoras' book is a huge bonus, their function in his argumentative or expository strategy often eludes us.

2 The original condition The first few sentences of Anaxagoras' book ran as follows: All things were together, unlimited both in quantity and in smallness.

For the small was indeed unlimited.

And with all things being together nothing was manifest on account of smallness.

For air and ether contained all things, both being unlimited.

For these are the greatest present among the totality of things, both in quantity and in magnitude.

(fr.

1) Much in this speculative story is mysterious.

What range or category of items count as ‘things' (chrēmata)? How is their 'smallness' to be understood? In what sense did air and ether 'contain' everything? What is the difference intended between their greatness in quantity and their greatness in magnitude? It was a characteristic trait of Presocratic writing first to grab the reader's attention with a memorable opening, and then to whet the appetite with a pregnant development whose full meaning and justification would emerge only gradually.

Anaxagoras provides a copybook example of the technique.

Only one other fragment describes the original condition: Before these things were separated off, when all things were together, not even any colour was manifest.

For the mingling together of all things prevented it - of the wet and the dry and the hot and the cold and the bright and the dark, much earth being present there also and seeds unlimited in quantity, in no way like each other.

For of the others no one is at all like another.

Since this is so, one must suppose that all things were present in the totality.

(fr.

4, second part) Putting the two passages together, we get the following lists of ingredients of the mixture: (1) air and ether (the predominant constituents), a lot of earth and seeds unlimited in number; (2) the wet and the dry, the hot and the cold, and so on.

The relation of lists (1) and (2) is obscure.

It may be that the wet and the dry and so on, simply are earth, air, ether, and so on, under another description, one particularly important for understanding the process of separation which initiates cosmogony.

There is also the question of which form of description Anaxagoras conceived as the more fundamental for ontology.

The major items listed in (1) are presumably the actual quantities of the material stuffs which dominate the universe as it is now. The identity and ontological status of Anaxagoras' seeds has been much debated.

The final sentences of fragment 4 suggest that he is once again extrapolating from what the universe at present contains to what it must be supposed to have contained originally.

A best guess is that from the irreducible present variety of an unlimited number of living species (plants as well as animals), he infers unlimited numbers of biological seeds in the original. »