Anaxagoras
Publié le 17/01/2010
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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.
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condition.
These he may have conceived as small particles - that would make sense of the explanation in fragment1 that nothing was manifest 'on account of smallness'.
So interpreted, Anaxagoras is making the general assumptionthat instances of whatever clearly differentiated species of living things now exist must also have existed at least inseminal form before cosmogony.
The thesis in fragment 1 - that there is no lower limit on how small something couldbe in the original condition - has as its counterpart the thesis that there is no upper limit on how large things canbe.
From fragment 2, which speaks of what surrounds our differentiated universe as unlimited in quantity, we caninfer that the totality was and is infinite in size.
Anaxagoras appears to argue the point about largeness by parity ofreasoning: For of the small there is no least but always a lesser (for what is cannot not be) - but also there isalways a larger than the large.
And it is equal in quantity to the small.
But with respect to itself each thing is bothlarge and small.
(fr.
3) Readers of fragment 3 have often been reminded of Zeno's paradoxes (see Zeno of Elea §§4- 6), although it is not known which philosopher wrote first.
Anaxagoras evidently differs from Zeno in finding thenotion of infinite divisibility basically unproblematic.
The similarity lies not just in the denial that there is a least, butin the metaphysical status of that claim, sustained as it is not by physical considerations but by reflection on ourconceptions of magnitude, and here particularly the logic of 'large' and 'small'.
3 In everything a portion of everything The evidence suggests that Anaxagoras next introduced the theme of the separation of the ingredients of the primordial mixture.
It looks as though this section of the book emphasized not the process itself nor itsoutcome in cosmic order, but a very general feature of reality as it is in its separated state: in everything there is aportion of everything.
Despite separation, there is a sense in which mixture remains the general condition of things.This paradoxical theory dominates the presentation of Anaxagoras' views in Aristotle and in what we can recover ofother ancient writers who report them.
Anaxagoras apparently appealed to several different lines of argument,perhaps designated 'signs' ( sē meia ) or 'evidences' ( tekm ēria ), in recommending the theory to his readers.
For one of these we have his own statement ( fr.
6 ).
Others are mentioned by Aristotle and the subsequent tradition; here only one sentence attributable to Anaxagoras himself survives ( fr.
10 ).
Most weight was accorded to an argument from growth (for example, A46 ).
Bread and water must contain hair, flesh, nails, bone, and so on.
Otherwise the ingestion of food would not make them grow: 'how could hair come from non-hair or flesh from non-flesh?' (fr.
10).As Aristotle puts it, Anaxagoras said that everything is in everything because he saw everything coming to be fromeverything ( Physics I 4).
A subsidiary argument developed a parallel story about opposites.
White has black in it: otherwise the brilliance of snow could not turn into the darkness of water (A97).
Anaxagoras made a similar point(details unknown) about heavy and light.
Finally, only if there were indivisible minima would it be possible formicroscopic pure stuffs to be isolated (fr.
6).
But as it is there is no lower limit on smallness (fr.
3), and indeed thesmall (that is, the latent) must be regarded as no less complex than the large (that is, the manifest): And since,too, there are portions equal in number of both the large and the small, in this way too all things will be ineverything; nor can they exist separately, but all participate in a portion of everything.
Since the least cannot be,none of them could be separated, nor come to be on its own, but as in the beginning so too now all things must betogether.
And in all things there are many even of those that are separating off, equal in number in both the largerand the smaller.
(fr.
6) Ancient and modern interpreters alike have been intrigued by the doctrine that there is something of everything in everything.
It has accordingly been subject to post-Anaxagorean theoretical refinementand elaboration.
Aristotle, followed by the doxographical tradition, inferred from Anaxagoras' arguments for it thatthe basic building blocks of his ontology were 'homoeomerous', that is, things whose parts were all the same incharacter as the whole ( fr.
6 ).
And he identified these building blocks as the bone, flesh and so on, introduced in the main argument (see, for example, A43, 46 ).
On two occasions he went so far as to claim that air and fire are not themselves elements but composites of 'these and all the other seeds' (see, for example, A43 ).
These interpretative moves are probably all mistaken.
Seeds certainly look to be fundamental items in Anaxagoras' system.But if it is right to suppose that they are conceived in biological terms, as containing what we would call thegenetic code for the various living forms which will emerge from them, none like any other, then they cannot beidentified with homoeomerous substances such as bone.
Indeed, in containing something of everything they willhave bone, flesh and so on, as actual or potential ingredients.
Whether biological seeds are themselveshomoeomerous seems irrelevant to their role in Anaxagoras' system.
Again, while Anaxagoras undoubtedly treatedbone, flesh and so on, as ingredients also of bread and water, it is unlikely that he regarded them as morefundamental than the animal seeds from which ultimately they emerge.
Lastly, to treat air and ether as compositesof other more elemental items is to reverse the whole direction of Anaxagoras' explanatory enterprise, which insistson the irreducibility of the variety of the world, and is guided by the maxim: 'The appearances are a sight of what isnot manifest' ( fr.
21a ).
Although Aristotle gave pride of place to homoeomerous stuffs in his account of Anaxagoras' ontology, he also acknowledged the elemental role of opposites.
Some modern scholarship has argued that thisrelative emphasis should be reversed.
In the surviving fragments it is certainly the opposites dry and wet, hot andcold, dark and bright and so on, which figure most prominently in Anaxagoras' most general statements aboutingredients of mixtures and separation from mixtures.
They also recur as the key factors in his explanation ofperception (see §5): we discern the cold by the hot, the drinkable by the brackish, the sweet by the pungent.
Thisevidence has suggested that the claim that there is a portion of everything in everything is to be understoodprimarily as the thesis that every substance or seed of an organism contains opposite powers of every sort - asfragment 4 puts it: 'forms and colours and savours of every kind'.
On this view, Anaxagoras may well have conceived such powers as more fundamental than air, ether, earth and living species, at least to the extent ofholding that such things derive their distinctive characters and causal properties from the particular combinations ofopposite powers which are inherent in them as portions.
The word 'portion' ( moira ) looks as if it may be an Anaxagorean technical term.
Modern scholarship has argued that it should be interpreted as equivalent to‘pro portion'.
On this view the point of its introduction can be elucidated by confronting an objection to Anaxagoras' thesis that 'each thing is or was most manifestly the things it contains or contained most of' ( fr.
12, end ).
Take the convenient if probably non-Anaxagorean example of gold.
If to count as gold a substance has to contain apredominance of gold, even though it has in it something of everything, must not the predominant gold itself contain.
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