Random? A Fluke? The Rise of Man and the Better View of “Chance and Natural Law In Epicureanism”

I wish to credit Jules Evans and a Facebook discussion for prompting me to return to a subject of supreme importance in Epicureanism.  Even more than the nature of “Anticipations,” the subject of “chance” is riddled with profound implications.  Against strong evidence to the contrary, the modern view of Epicureanism has become dominated by the idea that Epicurus held the atomic swerve to be the basis of a universe that is essentially “accidental” – the result of “chance” – and that but for “a fluke” all that we see around us and know to be true might have been absolutely and totally different.  [And with the further implication that it may be totally different tomorrow.]  One of the most profoundly troubling implications of this view, of course, is that man is himself an “accident,” and that human life arose simply through the random combination of elements.  This is similar to the argument that, given input of sufficient typewriters and monkeys, the works of Shakespeare will one day be the result.

Such was not the view of Epicurus.

To my knowledge, the best development of the contrary view — itself the majority understanding for hundreds of years — is that of Professor A. A. Long in his article “Chance and Natural Law in Epicureanism” published in 1977 in Phronesis, Vol. 22, No. 1, which provides exhaustive references and discussion.  For the remainder of this post I will simply quote from Professor Long’s argument, with the goal of providing enough to prompt the reader to study the full article.

First, we must define what we mean by “chance.”   As Long points out, “chance”:

may mean that the event or thing which they qualify is aimless, not something purposed or determined by an end.  This seems to have been Democritus’ conception of the world, and he did not contradict himself if he also said that all things are the necessary outcome of antecedent conditions.  Random in the sense of aimless is quite compatible with necessary.  Since Epicurus strenuously resisted the idea that the world is the outcome of any design or end to be attained, random or chance elements, in the sense I have just elucidated, are basic to his conception of things.  But this cannot be the point which Rist and others have in mind when they attribute random and chance events to the swerve of the atoms.  There is no need of any exceptional atomic movement to account for aimlessness and lack of purposiveness in Epicurus’ view of nature.  Paradoxically enough, the one phenomenon to which the swerve of atoms makes a certain contribution is the purposive movements of living things.  Natural events in general are aimless and therefore require no special freedom from normal atomic movement in order to be explained.


Up to the year 1879 it seems to have been generally assumed that human action is the only sphere of spontaneous or undetermined movement in the world of Epicurus.  This is the significant exception to the strictly mechanical causation or necessary chain of events which is otherwise evident in phenomena.  Human freedom was accounted for by an exceptional form of motion, the ‘swerve’ of atoms, and this ‘minimal’ deviation was also invoked to explain the ‘theoretical’ first contact between atoms from which worlds arise.  These, in fact, are the only functions of the swerve which are mentioned explicitly in Lucretius, and no word from Epicurus himself on the swerve has been discovered.

The only senses of chance, therefore, which concern us … are pure contingency, strict indeterminateness and spontaneity, since any other sense of chance is quite compatible with necessity.

The subject seems to me to be an important one, for if Bailey, De Lacy and Rist are right, Epicureanism was in the highly uncomfortable position of combining necessity and pure contingency, and this is paradoxical unless the limits of purely contingent happenings can be located. … A philosopher or scientist is entitled to admit exceptions to some natural law. But no one will take him seriously if he merely says: ‘this is a law of nature but I can’t say how far it extends’.  If Epicurus held that continuity of causation or natural law is a feature of all observable happenings in our world except human (or other animal) behaviour, and that only in this exceptional case does the atomic swerve contribute to these events, at least he could not be criticized in this way.  Was the orthodox view  …. correct after all?

I tragically will have to omit here the long citations to the original texts which Professor Long marshals in support of his argument.  He then returns to the true function of the swerve:

Since Epicurus does not tell us, explicitly at least, we naturally turn to Lucretius and there we find the existence of this atomic potentiality inferred not from unexpected or ‘chance’ happenings in the world but from a theoretical point – the need to bring atoms into contact – and the existence of libera voluntas (ii.216-293). There are no other phenomena which we can say were explained wholly or partially by reference to the swerve.  It would no doubt be wrong to rule out the possibility of atoms swerving in things other than the soul of living creatures.  But Epicurus could maintain, with some plausibility, that since the soul, as he understands it, is composed of the finest and most mobile of all atomic structures, it is only in this case that the minimal swerve of an atom breaks through the fati foedera and makes possible an observable event – animal action – which is not wholly determined by conditions already present in the world.


Epicurus modified Democritus’ cosmology by interpolating the need for ‘suitable atomic seeds’, but these too must be formed from atoms of congruent shapes. So, in the world once formed, the behaviour of new atoms is limited and governed by the basic structures to which they are assimilated. Stability and order arise not from the intervention of mind but as the necessary consequence of matter in motion. The indestructibility, size, shape, and motion of individual atoms limit the combinations which they can form, and thus in the world as we experience it definite kinds of things are evident.

But a most important class of ‘definite things’ in the world, and the one from which Aristotle’s defence of teleological explanation drew its strongest support, is animal species. The modern critic may be willing to acknowledge that Epicurus has a coherent, if simple, explanation of celestial movements and other regular natural phenomena – the primary structures of matter in the world and an infinite number of atoms with shapes appropriate to these structures. But does this, or any other explanation Epicurus can offer, provide an answer to Aristotle’s question, ‘why does man beget man’? The essence of reproduction is that species breed true, and there is no doubt that Lucretius at least held as fixed a view of species as Aristotle.’0 We have no surviving evidence from Epicurus himself on zoology, and any inferences about his views must be drawn from Lucretius. The zoological passages in his poem deserve more detailed study than I can attempt to give here, but it does not need extensive argument to show that he would answer Aristotle’s question along the following lines. Living things without exception are seen to originate from definite seeds (seminibus certis) such that their growth is invariably true to type. The phenomenon of reproduction is one of Lucretius’ strongest arguments for the existence of atoms: there must be changeless and indestructible bodies in order that the regularity of species may be maintained.  The changelessness and indestructibility of atoms, along with the fact that the universe contains an infinite number of atoms of every shape which it is possible for atoms to have (Lucret. ii.526-7), satisfy one necessary condition of regular species – the availability of suitable materials.

But the availability of suitable materials is not a sufficient condition for the regularity of species. Lucretius seems to recognize this when he asserts that there is a certa ratio which determines the certa semina of things, their certa genetrix and the fact that they grow (crescentia) true to type (ii.707 ff.). He is drawing attention to the limitations on possible atomic compounds – we do not see hybrids, half man and half beast, part animal and part plant. The reason for this is not only the certa semina of each species, but also the fact that in nutrition only those corpora are assimilated which can be joined to the structure of the creature’s body and move in harmony with this.  We may infer that the parents’ atomic structure is such that any seed they produce can only assimilate those atoms, by interaction with the environment, which fit the form predetermined by the parents. It is a rudimentary theory of genetics.  This theory of genetic development seems to be entirely consistent with the explanation of regular natural phenomena I have already discussed. It is also probable that Epicurus regarded the regularity of species as a second example of the manner in which the world’s primary structure has determined its subsequent history. In his account of the origins of life Lucretius insists that the earth is the mother not only of all vegetation but also of man and other animals (v.783-836). With the passage of time the earth has ceased to bring forth animals, and its function as mother of these has been taken over by union between the sexes of each species. But there is no suggestion that the offspring resulting from intercourse differ in form from those produced by the earth itself.  Some species have failed to survive, but those which persist today have not ‘evolved’. Epicureanism does not anticipate Darwinian natural selection. We may conjecture with Giussani that the fixity of species is to be traced back to the atomic structures which the earth contained during its time of fertility.

Within twenty-four lines [of Lucretius] there are six instances of tempore certo, and the phenomenon of dawn is related to other phenomena from biology and meteorology which also occur at a fixed time. Therefore, Lucretius concludes, there is nothing mirabile in the regularity of dawn, and he  rounds off his argument:  “namque ubi sic fuerunt causarum exordia prima atque ita res mundi cecidere ab origine prima,  conseque quoque iam redeunt ex ordine certo.”   This statement was rightly interpreted by Giussani for what it is  –  an expression of strict causality.  Events recur in a regular sequence following  the  causarum exordia prima which  operated at  the  world’s  beginning. …  Certainly the  Epicureans wished to  avoid any  suggestion of purposiveness in their  explanations of order in the world.  But the emphasis of our text is not  on the world’s unplanned origin and organisation but on the certus ordo which follows from its  primary structure.

A number of conclusions may now be stated.  First, the consistency between Epicurus and Lucretius is too great to support the suggestion, which has been made in the past, that the poet’s emphasis on foedera naturae is a later development in Epicureanism.  Secondly, references to chance in Epicurus and Lucretius do not imply, as many modern scholars say, that sheer contingency or spontaneous events play a part in nature along with necessity. The world arises as a result of purpose- less atomic movements, and Epicurus gave at least one spontaneous atomic movement or swerve a function in explaining the origin of worlds. But within our world, as we know it, law-like regularities hold good and will continue to do so as long as the basic structure of the world remains intact. A causal sequence, which can be traced back to the formation of the world, determines natural events. Thirdly, human (and perhaps other animal) behaviour is not entirely dependent on this causal sequence. The structure of the mind is such that swerving atoms among its constituents free behaviour from being wholly determined byantecedent causes. But no word from Epicurus or Lucretius connects chance events in the world with the atomic swerve.

If  the  general line  of  argument in  this  paper is  sound, Epicurus confined the verifiable evidence of the swerve in nature to ‘free’ animal behaviour.  It is worth noting that his denial of necessity to propositions of the form ‘Either Hermarchus will be alive tomorrow or he will not’ is illustrated by an example referring to man.  Epicurus was most anxious to  free human actions from necessity.  But  in  other respects he  developed the  model of a world which conforms to  natural law.     If  Epicurus  was  to  let nature explain all phenomena  and thus discharge gods and final causes from any place in the world, he could make only the most minimal concession to spontaneous or purely contingent events.  The atomic swerve is nec plus quam minimum, and I  conjecture that  the scope of its operation in the world is equally minimal.


NOTE:  Yes, fans of Norman DeWitt, Professor Long’s view was apparently that of DeWitt as well.   As Professor Long cites, from page 175 of Epicurus and His Philosophy:

It may be here interposed that the concept of determinism is not offensive to the intellectualist. It was consequently the duty of Epicurus as a moralist, a reformer, and hence a pragmatist, or in ancient parlance, as a truly wise man, “who will be more powerfully moved by his feelings than other men,” to declare the significance of determinism for human conduct. His verdict was that it meant paralysis. His solution was to postulate a sufficient degree of freedom in the motion of the atoms to permit of freedom in the individual. This is the doctrine of the swerve.

For the sake of a closer analysis it is worth while to observe at this point that Epicurus, having put the mythologers and the physicists in a single class as teachers of fatalism, wished his disciples to see the new order of his own system as governed by the laws of Nature, foedera naturae, as opposed to the laws of Fate, foedera fati.  Consequently the new freedom he was offering to mankind “had been wrested from the Fates,” fatis avolsa potestas. In an infinite universe dominated by these physical laws man is miraculously exempt. He is free to walk forward and to turn left or right of his own untrammeled volition. Neither in respect of time nor in respect of place is his action predetermined down to the moment of its beginning. The laws of Nature are in the main restricted to the world of inorganic things.

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