the modern misunderstanding of aristotle's theory of motion oded balaban

7/28/2019 The Modern Misunderstanding of Aristotle's Theory of Motion Oded Balaban

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THE MODERN MISUNDERSTANDING OF ARISTOTLE'S THEORYOF MOTION

ODED BALABAN

SUMMARY. In the Physics, Aristotle defines motion as 'the actuality of what is potentially,qua potential' (Phys. 201b5). This definition has been interpreted countless times and hasbeen the subject of heated controvery. At issue today is whether e*>reAexeia refers to motionsas a process or a state. Accordingly, if the idea of evTek'extia is believed to refer to a process,it is translated to mean actualization. If on the other hand it is taken to refer to a state,it is translated as meaning actuality. In the first instance, known as the 'state-view', a changeis defined as being the state of a changing object when it is actually potentially F, for some

F1. In the second, or 'process-view', a change is defined as the actualization of a potentially.2It seems to me that both views mistakenly assume that Aristotle succeeded in defining

motion as motion. As a consequence, the discussion has focused on a presumed contentthat the definition does not offer. Indeed, were it the case that Aristotle's definition wasadequate, there would hardly be any point in even considering the question of whether hehad intended to regard motion as being a state or a process. In this paper I examine bothof these views and offer an alternative interpretation of my own that differs markedly fromeither. Additionally, I shall show that just as Aristotle's definition represents a projectionof his particular attitude toward nature - so also recent interpretations of his definition representa projection of the attitudes of modern thinker's toward Aristotle's philosophy.

Key words: motion, actuality-potentiality, form-matter, praxis-poesis, process-result.

THE CONCEPT OF MOTIONAristotle defines motion as 'the actuality of what ispotentially, qua potential'(Phys. 201b5) or as 'the actuality of what is potentially, as such' (77 tovSwa/iet, bvros tWeAexeia, 17tolovtov) (Phys. 201all).3 The main pointat issue in the modern controvery is about how to understand the ideaof potentiality.

According to the process-view, when something is potential it is actuallythat at a given moment - for example, the process by which the buildablebecomes buildable. The final product is according to this view totallyirrelevant to the definition of change or motion. If this were so, then Aristotlewould have referred to, say, the materials out of which a building wasbuilt as the actuality of bricks and stones qua bricks and stones; or asthe process of being bricks and stones as such, irrespective of their purpose.Change would therefore be the process of this process of being bricks andstones as such. It would therefore be a case of defining the buildable quabuildable - or, as Kosman puts it, of defining 'the process by which thebuildable becomes buildable, rather than, as Aristotle has inmind, building,that is, the process by which the buildable becomes built.4 But then the

Journal for General Philosophy of Science 26: 1-10, 1995.? 1995 Kluwer Academic Publishers. Printed in the Netherlands.


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actual-potential distinction would lose its meaning. Change would be, asit were, the process of this process of being bricks and stones. That isto say, motion would be absurdly defined as the motion of motionin

which case potentiality would not be defined in terms of actuality, andthis would run counter to Aristotle's definition of these terms. Aristotleexplicitly suggests that potentiality per se cannot exist (cf. Phys. 201 b 33202 a 1).The state-view shares assumptions that are similar to these of the processview. Change is defined as the state of the changing object when it is actuallypotentially F, for some F. Therefore being 'only potentially F' (which isdifferent from being 'actually potentially' F), means being potentiallypotentially F But this results in a confusion of terms. Actuality andpotentiality are technical concepts developed by Aristotle for the expresspurpose of distinguishing between what is inmotion and what is not, betweenthe incomplete and the complete - where motion betokens incompleteness.According to this interpretation, it would appear that Aristotle definedmotion as the completion of the incomplete. However Aristotle explicitlyrejects this possibility when he denies that motion is an absolute and simpleactuality (cf. Phys. 201b 25-30).Both of these interpretations assume that Aristotle was indeed capableof arriving at a definition of motion as such, when in fact no such accountcould have been given by him. Formulated in the most extreme terms,both views end in absurdity. If motion is taken to be a process, then weare confronted by a circularity of definition. What is being asserted is thatchange is change; and motion is thereby defined as the actuality of whatis potentially motion qua potential motion. As Kosman has rightly observed,'to say that motion is the process of actualization by which a potentialityis actualized is to attempt to define motion in terms of the very conceptin question, that of the process of actualization'.5 On the other hand, ifmotion is regarded as a state, the implication is that change is definedby what does not change, or that motion is no-motion but rest - whichismanifestly a contradiction. Thus the controversy over whether hrekexetameans a process or a result boils down to this: in avoiding entanglementin a tautology, one is trapped in a contradiction. And in avoiding theentanglement of contradiction, one is entangled in either a tautology orcircularity of argument.Modern advocates of the process-view and of the state-view agree inthat 'potential' is the equivalent of 'change-as-such'. This is however notthe case. Indeed, according to Aristotle, there is no change-as-such; ratherchange is toward something else that is in itself unchangeable. For Aristotle,potential is the equivalent only of change, and neither has meaning in itself,but only concerning some end. The frame of reference for giving an accountof motion is always the unchangeable final product.

According to Aristotle, potentiality is the process that something is inwhen it has not yet assumed its final form - for example, the process by


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which the buildable becomes built. In this instance, potentiality refers toa house whose construction is yet incomplete. The point is that potentialityper se, without its end being taken into account, is as incomprehensibleas would be the process of building without taking into account what isbeing built.To understand Aristotle's theory of motion, we have to begin byconsidering the assumption that underlies the theory. The first questioniswhether motion is definable for itself or concerning something else. Thereis any sense in determining whether motion is a process or a state, onlyifmotion is definable for itself. However, Aristotle maintains that motionis definable only concerning something else other than itself - or morespecifically, in relation with its opposite, which is rest. And since Aristotlecannot offer an immanent definition of motion, the whole issue of whether

motion is a process or a state - and therefore the very controversy amongmodern interpreters - is irrelevant to his definition.Aristotle offers only a paradoxical definition of motion. This is not tosay that he denies its existence. This would have been the position of theEleatic school, which Aristotle criticized. Aristotle recognizes that motionexists, but regards it as impossible, or at least difficult, to be grasped.6The epistemological difficulty lies in the very idea of potentiality. Accordingto Aristotle, something cannot exist qua potential, or potentially in itself.In this, potentiality is like matter. Matter can exist only if it is actual -or, what amounts to the same thing, if it possesses a form. And sincemotion as such must be defined in terms of potentiality as such, it cannotbe defined within the framework of Aristotle's system of thinking.Indeed the same problem arises concerning the definition of matter asin the case of motion. Form precedes matter - which is to say that matteris explained by means of form. Matter qua matter exists neither ontologically (Metaph. 1029) nor epistemologically (Metaph. 1036). Matter is precisely that which does not change; in other words, matter is that whichdoes not exist in itself. Existence is that in which change is given - namely,form (Metaph. 1070-1). Thus Aristotle cannot define motion as either aprocess or a state since he gives no consideration to change as such. Changeis the transition of matter from one form to another, and this can be graspedonly as a transition from the potential to the actual. But transition perse is undefinable. For to attempt to define it is like trying to define matterwithout form; and this is obviously beyond the scope of Aristotle'sphilosophy. Aristotle offers no principle of change-in-itself. He is onlycapable of considering form as either final form or transitional form (thatis, the transition from one form to another), which is an alternative possibility that neither the process-view nor the state-view takes into account.Stated in the most general terms, actuality precedes potentiality, in thatpotentiality is explained by means of actuality (Metaph. 1049-50). Rest(that is, the end) therefore precedes motion, and the former explains thelatter.7 Hence the only definition of motion offered by Aristotle, taking


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into account the whole corpus of his writings, is paradoxical.Let us consider alteration as an instance of motion (cf. Phys. 225 b 10226 b 17).What ismotion {klvyjol^) in the sense of alteration {a\\oia>oi


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MISUNDERSTANDING OF ARISTOTLE'S THEORY OF MOTION 5Motion is therefore grasped through its opposite. Aristotle is undoubtedlyconscious of the difficulty implied here, as is evident when he contendsin this regard that "it is hard to grasp what motion is" (Phys. 201 b 33).Motion has to be characterized as a deficiency - as a potentiality withoutactuality; so that, like matter without form, it is beyond comprehension.Motion is therefore not definable in its own right, so that there is nodefinition of motion proper. Motion is not definable in terms of itself,but only by means of its limits - by its terminus ad quo and terminus adquem\ by what precedes it and comes after it.13

THE ORIGIN OF THE CONCEPT OF MOTIONLike all the Aristotelian ontology, Aristotle's ontology of motion originatesin the model of human activity. However he is unaware of this. Indeed,he even inverts the relationship. So, for example, he contends that art isan imitation of nature, since it consists in bestowing form on the matter.14Yet Aristotle conceives nature as oriented toward a goal (Phys. 199). Aristotleregards nature as imitating human art. Thus his theory of nature is a constructderived from human activity.

According to the principles of the form-matter and actuality-potentialitydistinctions, Aristotle distinguishes between production on the one hand,and consumption and use on the other. Aristotle is unaware that he hasreversed the order of these distinctions. He is also unaware that hisdistinctions between form and matter, and between actuality and potentiality, are an inversion of his basic model. Basically, he distinguishes betweenhuman production and consumption (or use), where matter is the objectof TToi-qois, and form is the object of 7rpafi9. Therefore, to understandAristotle's conception of nature in general, and of motion in particular,it is necessary to analyze his conception of

men and society.Aristotle distinguishes between two kinds of human activity: irpa^is andnoi-qois (Metaph. 1048b). The first is not motion, and the second ismotion(Eth. Nich. 1140b). InMetaphysics 1048b, a key passage for understandingthe problem of motion, Aristotle contends that while all motion is incom

plete, actuality is always complete. Completeness and incompleteness haveto do with whether the reAo9 is in the activity itself or in its end; in thelatter case, motion is subordinated to the end. An activity that is in itselfa re\o9 is called by Aristotle 7rpaft9. In this passage, the completenessof irpaZi9 is set in opposition to motion. For this reason, ttoltjol^ is ethicallyinferior to 7rpa?i9. Upat; 19 is the model of moral behavior, since in ethics,"doing well is in itself the end" (Eth. Nich. 1140b7). It should be notedthat the completeness of npa^is does not mean quietude of being. Quietudeof being is rather the correlative of uncompleted motion,15 which attainscompletion only when it ceases. Thus quietude of being is already to haveacquired learning, rather than learning itself; or to have arrived at a place,rather than traveling to it.


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Ilpaf t9 refers to the end of the activity, and iroLrjoLs refers to the means.Thus the TrpaJjis-TroirjoLS distinction overlaps the distinction between endsand means. Ilpafis is the form of the activity of the consumption anduse of things that are neither made for consumption nor serve as a meansto an end other than themselves. Thus Aristotle cites the example of abed as a means of npoL^is {Pol. 1254a). On the other hand, productiveuse requires instruments that are different in kind from those employedin consumption. These instruments are means to an end other than theiruse - say a shuttle {Pol. 1254a).The distinction between 7rpafi9 and tyoivols is so sharp, that differentclasses of individuals characteristically function in one or other of thesetwo activities. Masters, by their very nature, function as consumers, namely,as subjects of Trpagts while slaves are characteristically producers, that is,subjects of TroLrjoLs.The latter have no independent existence, they existonly to execute the master's orders, that is, to achieve his ends.16 Slaves,as subjects of Troirjois, that is, as consumers, do not participate in theactivity of consumption.17 Masters on the contrary, as subjects of npalzisand, consequently, as consumers, do not participate in the activity ofproduction.18 Even when they appear to be doing so, by imparting ordersto the slaves, they are still acting within the framework of 7rpaft9. Theyare merely using their slaves, and using is a mark of npcx^Ls, not of 77-0177019.This strange assertion becomes comprehensible within the framework ofAristotle's intention to distinguish sharply between motion and perfection,TrolnoLs and npa^ 19,potentiality and actuality. The polar distinction betweenmaster and slave is essential for the clear distinction of his own categories.Without it, the relational ideas of noi-qois and 7rpafi9, potentiality andactuality, motion and perfection, would become merely relative and,therefore, problematic. Aristotle is trying precisely to avoid this relativizationof his categories. His definition of motion as such (that is, of potentialqua potential) leads just to such a relativization of the relational ideasof actual and potential. Aristotle therefore does the very things he soughtto avoid.

To maintain his sharp distinction between master and slave, Aristotlefurther distinguishes between two kinds of instruments: instruments of7rpa^t9 and instruments of 77-0177019.ristotle consider slaves as instrumentsof Trpoi?is and not of 71-0177019, ince the master's acts in relation with hisslave are acts of 7rpaf t9. It is the instruments of the slaves that are instrumentsof 77-0177019,hat is, their activity is productive. Aristotle states:Instruments are of various sorts. Some instruments are living, others lifeless. In the rudder,the pilot of a ship has a lifeless, in the lookout man, a living instrument; for in the artsthe servant is a kind of instrument. Thus, too, a possession is an instrument for maintaininglife. So, in the arrangement of the family, a slave is a living possession, and property a

number of such instruments; and the servant is himself an instrument for instruments. Forif every instrument could accomplish its own work, obeying or anticipating the will of others,like the statues of Daedalus ... if the shuttle would weave and the plectrum touch the lyre,


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MISUNDERSTANDING OF ARISTOTLE'S THEORY OF MOTION 7chief workman would not want servants, nor masters slaves. Now the instruments commonlyso called are instruments of production whilst a possession is an instrument of action (npalzis).From a shuttle we get something else besides the use of it, whereas of a garment or ofa bed there is only the use. Further, as production and action are different in kind, andboth require instruments, the instruments which they employ must likewise differ in kind.But life is action (Trpa^t?) and not production (Troi-qois), and therefore the slave is the ministerof action ... The master is only the master of the slave; he does not belong to him, whereasthe slave is not only the slave of his master, but wholly belongs to him {Pol. 1253b28-1254a 14)

From the point of view of my thesis, the point of interest in the abovequotation is that the slave functions, in relation with his master, as a processor motion. Whereas the master represents the end that imparts purposeand meaning to the existence of the slave. As in the case of motion, heretoo, 'complete' is that who serves its end (the master) or that who achieveshis end. 'Incomplete' is the slave, who is not defined in himself but onlyin relation with his master. 'Incomplete' also is that which has not yetachieved its end, that which is still in the process of production. It becomescomplete or perfect when the process is completed and the object becomesavailable for consumption or non-productive use.This sharp distinction between npa^Ls and irol-qois is the basis for thedistinction, in Aristotle's general interpretation of nature, between naturalprocess and result. Nature is not taken to be a natural process as such.Nature is grasped by virtue of its fruits: you understand a seed byunderstanding the mature plant into which it should develop, as youunderstand production by virtue of the product (cf. Phys. 199). Natureis therefore grasped by the idea of TrolrjoLs, that is an idea subordinateto the idea of Trpaizis. Like human beings, nature also uses means to achieveends. However, the fruit or product of nature, as of human activity, isdistinct from the process of production (that is, motion).This view of motion as dependent on ends has not only theoretical butalso practical significance. Aristotle based his philosophy upon the generalassumption of his time, that men do not generate motion but they merelymake use of it.Motion, according to Aristotle's basic assumptions, is notconsciously generated. Motion is not definable as such. It iswhat lies betweena state where it has not yet come into operation and the state where ithas already ceased to operate. Therefore the question raised by thecommentators (that is, whether motion, for Aristotle, is a process or astate in itself) ignores this fundamental aspect of Aristotle's philosophy.

Their question ismotivated by modern physics rather than by Aristotelianassumptions. Contrary to modern technology, the Greeks did not createnatural motion. The Greeks grasped natural motion only in use; it wastherefore cognizable not as such but only as goal-oriented. Aristotelianphysics (that is, nature) is ultimately analogous to art and production that,like motion, are goal-oriented. Therefore, motion cannot be regarded eitheras a process or as a state in itself.For the assertion of motion as a process, Aristotle would have to


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acknowledge the generation of motion, and to define motion as such. Buthe defines it only in relation with its result. Therefore, motion is a potentialresult and only as such it can be grasped. For the assertion of motionas a state, Aristotle would have defined motion not as such but in termsof its result.

Modern physics bases its opposition to Aristotle's theory of motion onartificial, produced motion. Modern physics explains the production ofmotion by means of natural laws, since natural laws are the conceptualexpression of the mode of motion itself. The knowledge we need to producemotion is not about motion but about the mode of motion.

The modern misunderstanding of Aristotle's approach derives, I believe,from the application of modern patterns of thoughts to ancient categories.The process view of Aristotle's interpreters is plausible only if motion isgrasped in itself and not through rest. This is precisely what modern physicshas attempted to do, but not so Aristotle. We may therefore assert thatthe process-view interpreters are trying to interpret Aristotle's idea of changethrough the categories of modern physics. Modern physics, unlike Aristotle,cannot understand rest as such, and therefore defines it in terms of motion:as an equilibrium of forces. Aristotle, on the other hand, defines motionin terms of rest. We must therefore try to understand Aristotle's approachnot through, but in opposition to modern physics. Whereas modern physicsregards motion as the primary state of things, Aristotle regards rest asthe primary state of things. Motion he regards as a secondary state and,as such, he seeks to explain it. Aristotle asks what motion is, but explainsit only indirectly as a transitory stage whose end is a state of rest. Modernphysics, on the other hand, explains motion directly and not in terms ofrest. So that, just as modern physics cannot understand rest qua rest, Aristotlecannot understand motion qua motion.19

The new idea of motion developed by modern physics superseded theclassical Aristotelian idea of being. The classical idea of rest was correlativeto the idea of being. Being, in the sense of being-at-rest, was the end bywhich motion was explained. Therefore the idea of motion for the classicistswas closely related to the idea of place, since to be at rest means to beat a certain place. For Aristotle, things are in motion when they are notin their natural place. Hence, when they reach their natural place, motionceases. However, modern physics (after Kepler's assertion that place is acreation of the mind "omnis locatio mentis est opus"20 denies the existenceof a natural place for things. It has shifted the explanation of physicalreality from place to change of place.11 This shift of the explanatory criterionis a shift from explanation in terms of substance to explanation in termsof functions or in terms of laws. The idea of law has superseded theAristotelian idea of Reality. For Aristotle, motion is a state of imperfection.For modern physics, motion is the natural state of things. Modern physicsdoes not explain motion by some other state (in this case, rest). Accordingto Aristotle, klptjols can only be grasped through a reXo9 that is not itself


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motion, whereas modern physics does not need a reXo9 to explain motion.Galilei goes so far as to assert that what is at rest does not even exist.22Similarly, Newton, in his First Law of Motion, refers to the conservationof motion. This modern approach cannot be grasped in terms of theAristotelian motion-rest correlation. Motion is not definable by its end.23

Kepler, too, refers to a perpetual, eternal motion, one that does not haverest as its end.24 Kepler explains his own approach as an attack on theAristotelian idea of final cause.For Aristotle, on the other hand, effective cause (motion) is subordinateto final cause (rest). The distinction between motion and its end pervadesall his philosophy and gives it its particular character. Like motion, matter

is subordinated to and defined by form; Troiiqois is subordinate to TrpaJjis;servant to master; potentiality to actuality; means to ends. This distinctionis based upon the primacy of the result over the process, in the sense thatthe result explains the process, which is apprehensible only in terms ofits end.

NOTES AND REFERENCES1The state-view is sustained in different versions and issues by: L. A. Kosman: 1969, 'Aristotle's

Definition of Motion', Phronesis 14, 40-62; Jaakko Hintikka: 1977, 'Aristotle on Modalityand Determinism', Acta Philosophia Fennica XXIX, 58-77; Mary Louise Gill: 1880, 'Aristotle'sTheory of Causal Actions in Phys. Ill 3', Pronesis XXV, 129-147. In the state-view, motionis not defined in itself but defines a thing in a state of changing.2 The process-view is sustained by Terry Penner: 1970, 'Verbs and the Identity of Actions',in Oscar P. Wood and George Pitcher (Eds.), Ryle: A Collection of Critical Essays, Garden

City: Anchor Books, pp. 393-460. W. D. Ross: 1936, Aristotle's Physics, Oxford, p. 537.Edward Zeller: 1921, Philosophie der Griechen, Leipzig, II, 2, 351. James Kostman: 1987,'Aristotle's Definition of Change', History of Philosophy Quarterly IV, 3-16.3 Cf. also Phys. 202a6, 251a9, Metaph. 1065bl6, 1065b23.4 Kosman, op. cit. p. 43.5 Kosman, 'Aristotle's Definition of Motion', p. 41.6 The knowledge of motion has a philosophical evolution. At the beginning, motion was

presupposed, and therefore it was not something explainable. Afterwards, with the Eleaticschool, motion becomes an object of analysis although denied its existence. Plato recognizedit as an illusion. Aristotle went forward, recognized its existence and, instead of deny it,considered motion as difficult to be grasped.7 For a good account of the idea of change (motion) as different from the idea of activity,see Mary Louise Gill: 1880, 'Aristotle's Theory of Causal Action in Physics III 3', PhronesisXXV, 129-147.8 This analysis of motion is inspired in Jose Ortega y Gasset's Preface to the Spanish translationof Emile Brehier's Histoire de la Philosophie, Buenos Aires: Sudamericana, 1942, pp. 42-47.9 Cf. Phys. 201 b, 257b9, Metaph. 1048b29, 1066a20.10T. Penner: 1970, 'Verbs and the identity of actions - a philosophical exercise in theinterpretation of Aristotle', in O. P. Wood and G. Pitcher (Eds.), Ryle, Macmillan, pp.430 ff.11Phys. 257 b 8. Cf. Penner, op. cit., 433.12L. A. Kosman gives a good insight about the impossibility of defining motion: 'For motionis the actuality of a potentiality which is aimed ultimately at an actuality other than the

motion and fatal to it. Motion does not, therefore, just happen to cease, its essential activity


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10 ODED BALABANis devoted to ceasing. Its being is auto-subversive, for its whole purpose and project is one

of self-annihilation'. Kosman: 'Aristotle's Definition of Motion', p. 57.13 In De Anima, it seems that Aristotle takes another approach. There he distinguishes betweentwo opposite ideas of actualization: (a) actualization as the destruction of potentiality, and(b) actualization as its conservation. That is to say, there is a negative meaning (destructionof potentiality), and a positive meaning (its conservation) of actualization. Thought, for instance,is not a change, since change implies destruction (cf. De Anima 417b); it is rather conservation,'progress toward itself or 'on itself as an inner return to actuality. But Aristotle adds 'towardsits end', and therefore he does not change his basic approach, that is, the reference to the end.14Cf. PA. 639b. Nature aims at the best and noble PA. 645 a 25, 670 b 24; nature is rational(G.A. 731 a 24, 744 b 15). Cf. also G.A. 760 b 26. Compared with art: GA 734b 20 735a1, 762al5, 775a20. With an artisan: G.A. 731 a 20, 730 b 15, 743a 25. Nature does nothingin vain: PA. 658 a 9, DC2.15 In Aristotelian language it is redundant to speak about imperfect motion, since motionmeans already lack of perfection; notwithstanding, I use this expression to facilitate theexposition of the subject.16 '... Some men are by nature free, and others slaves, and that for these latter slavery isboth expedient and right' (Pol. 1255al). English translations are from Jonathan Barnes (Ed.):1984, The Complete Works of Aristotle, Princeton.17 'The best form of state will not admit them [the artisans] to citizenship; but if they are

admitted, then our definition of the excellence of a citizen will not apply to every citizen,nor to every free man as such, but only to those who are freed from necessary services'{Pol. 1278a 5-13).18 '... the citizens must not lead the life of artisans or tradesmen, for such a life is ignobleand inimical to excellence. Neither must they be farmers, since leisure is necessary both forthe development of excellence and the performance of political duties' (Pol. 1328b37-1329al).19Michael Boylan missed this point by asserting that the logic of modern science, especiallythat of biology, is similar to Aristotle's logic. Boylan fails to see the difference between the

Aristotelian question concerning the what (the end) and that of modern Science concerningthe how (the process). Cf. Michael Boylan: 1984, 'The Place of Nature in Aristotle's Teleology',

Apeiron XVIII, June.20 Johann Kepler, Opera Omnia, V. II, 55.21 See Ernst Cassirer: 1923, Einstein's Theory of Relativity, Chicago, The Open Court Press,p. 362.22Galileo Galilei, Dialogo, Berkeley, 1953, p. 58.23 Sir Isaac Newton, Philosophiae Naturalis Principia Mathematica (1687), Berkeley 1947, p. 13.24 See De Anima 417b5. J. Kepler, Gesammelte Werke, V. VII, Book IV, part. 3, p. 330.

Dept. of Philosophy,University of Haifa,Mount Carmel,Haifa 31999,Israel.

the modern misunderstanding of aristotle's theory of motion oded balaban

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