Autor: Lonergan, Bernard J.F.

Buch: Verbum: Word and Idea in Aquinas

Titel: Verbum: Word and Idea in Aquinas

Stichwort: Aristoteles, Thomas; actus perfecti - imperfecti -> operatio - motus (energeia - kinesis); actus existentis in actu

Kurzinhalt: The substance of what Aquinas meant by actus perfecti and actus imperfecti is contained in the foregoing account of Aristotle. He referred to this contrast variously as a difference between operatio and motus?

Textausschnitt: 8/3 Excessive attention to the metaphysical framework with insufficient attention to the psychological content of the Thomist concept of verbum has led to a good deal of obscure profundity on the meaning of Aquinas's actus perfecti. It is necessary for us to set forth the evidence on the meaning of the phrase, and in doing so it will be well to begin from Aristotle, first because it is only a translation of Aristotle's energeia ton tetelesmenou,1 and secondly, because Aquinas, when first he uses it,2 takes it for granted that the reader knows his Aristotle and so knows what it means. Our account of Aristotle may be divided into three parts: general contrasts between operation (energeia) and movement (kinesis); the analysis of movement in the Physics; and the recurring embarrassment in the De anima occasioned by the specialization of terms in the Physics. (110f; Fs)

9/3 In the Ethics >ARNE_09_10> there is considered a Platonist argument to the effect that pleasure is not the good because pleasure is a movement and so incomplete, while the good must be complete and perfect. It is met with the observation that all movements have velocities, that pleasure has no velocity, and so pleasure cannot be a movement nor be incomplete.3 On a later page the incompleteness of movement and the completeness of operation are described at greater length. A movement becomes in time; one part succeeds another; and a whole is to be had only in the whole of the time. On the other hand, an operation such as seeing or pleasure does not become in time but rather endures through time; at once it is all that it is to be; at each instant it is completely itself. In a movement one may assign instants in which what now is is not what later will be. In an operation there is no assignable instant in which what is occurring stands in need of something further that later will make it specifically complete.4 (111f; Fs) (notabene)

10/3 A similar general contrast occurs in the Metaphysics. There is a difference between action (praxis) distinct from its end and action coincident with its end. One cannot at once be walking a given distance and have walked it, be being cured and have been cured, be learning something and have learned it. But at once one is seeing and has seen, one is understanding and has understood, one is alive and has been alive, one is happy and has been happy. In the former instances there is a difference between action and end, and we have either what is not properly action or, at best, incomplete action - such are movements. In the latter instances action and end are coincident - such are operations.5 (112; Fs)

11/3 The characteristics of movement, described in the Ethics and the Metaphysics, are submitted to analysis in the Physics. The nature of movement is difficult to grasp because it is a reality that, as reality, is incomplete and so involves the indeterminate.6 Still, movement may be defined as the act of what is in potency inasmuch as it is in potency, or as the act of the movable just as movable.7 Again, one may say that what is about to be moved is in potency to two acts: one of these is complete and so admits categorial specification; but this act is the term of another which is incomplete and so does not admit categorial specification; movement is the latter, incomplete act.8 Since this definition does not presuppose the concept of time, it is employed in defining time.9 Next it is shown that the incomplete act, movement, can occur in only three categories, namely, place, sensible quality, and physical size.10 It is insisted that movement can be had only in a corporeal, quantitative, indefinitely divisible subject.11 From the indefinite divisibility of distance and time it is concluded that in a local movement not only is there a moveri prior to every assignable motum esse but also there is an assignable motum esse prior to every assignable moveri;12 thus analysis pushes to the limit the descriptive contrast between the specific completeness of operation and the specific incompleteness, the categorial indeterminacy, of movement.13 But just how the demonstrable paradox of local movement was to be extended to alteration, growth, generation, and illumination was for the commentators an obscure and disputed point.14 (112f; Fs)

12/3 As the Physics analyzes movement, so one might expect the De anima to analyze operation. But if that expectation is verified substantially,15 there is a far more conspicuous embarrassment caused by the specialization of terms in the Physics. For in the De anima, despite the alleged wealth of the Greek language, Aristotle needed such words as kinesis, alloiosis, pathesis, in a fresh set of meanings; but instead of working out the new meanings systematically, he was content, in general, to trust his reader's intelligence and, occasionally, to add an incidental warning or outburst. Three examples of this may be noted. First, there is the remark that, because movement (kinesis) is an act (energeia) even though it is an incomplete one, we may take it that undergoing change (paschein) and being moved (kineisthai) and operating (energein) are all the same thing.16 Again, there is the explanation that the phrase 'undergoing change' (paschein) is not univocal: when the scientist's science becomes actual thought, the becoming is not an alteration or, if it is, then it is alteration of a distinct genus.17 In similar vein the third book of the De anima contains the statement to which Aquinas regularly referred18 when contrasting actus perfecti and actus imperfecti: the movement of a sense is movement of a distinct species; for movement has been defined as the operation or act (energeia) of the incomplete, but operation simply so called is of the completed.19 (113f; Fs)

13/3 The substance of what Aquinas meant by actus perfecti and actus imperfecti is contained in the foregoing account of Aristotle. He referred to this contrast variously as a difference between operatio and motus?20 or as a twofold operatio21 or finally as a twofold motus.22 Actus imperfecti was explained by noting that what is moved is in potency, that what is in potency is imperfect, and so that movement is the act of the imperfect.23 Both early and late works testify to a full awareness that movement is intrinsically temporal and specifically incomplete.24 In contrast the actus perfecti is defined as 'actus existentis in actu,'25 and even as 'actus existentis in actu secundum quod huiusmodi';26 it is specifically complete, an 'operatio consequens formam,'27 the 'operatio sensus iam facti in actu per suam speciem,'28 without need or anticipation of any ulterior complement to be itself,29 and intrinsically outside time.30 (114f; Fs)