Aristole’s Incomplete Causal Theory

ARISTOLE'S INCOMPLETE CAUSAL THEORY I N THIS STUDY I wish to show that in the Physics Aristotle holds what in effect are two incompatible theses as regards causality. These theses are (A) that actual causes are simultaneous with their effects, and (B) that the efficient cause of a thing's coming-to-be is identical with the efficient cause of its being (existence). Further, I want to show that as a result of his commitment to these incompatible dicta, Aristotle's doctrine of causality is schematically or in its broad outlines incomplete. And yet, it need not be such. For once the inconsistency is removed by denying (B) , the way is then cleared for making Aristotelian causal doctrine structurally complete. Third, I shall contend that as a matter of fact it was Aristotle's medieval disciple St. Thomas Aquinas who, while retaining (A), both denied (B) and offered a positive prescription for completing the Philosopher's doctrine of causality. Finally, I suggest that Aristotle's commitment to (B) is occasioned by his failure to keep clearly in mind the distinction between a thing's essence and its act of existing. I In order to bring out clearly the incompatibility referred to, I shall first spell out the precise meaning of efficient causality in Aristotle. This is all the more necessary in view of the fact that, since some scholars deny that Aristotle ever held (B) to begin with/ they would deny that any inconsistency of the sort being alleged here can be found in his thought. To help eluci1 In his The Doctrine of Being in The Aristotelian Metaphysics (Toronto, 1963) J. Owens, for example, says: "Efficient cause is introduced as a correlate of cllange, not of Being. It is repeatedly characterized as ' that from which movement originates.' No ground is given in the text for reading into it later notions like·that which gives existence.'" (p. 193 n. 103) 420 ARISTOTLE's INCOMPLETE CAUSAL THEORY 421 date Aristotle's notion of efficient causality and at the same time to see why some critics mistakingly deny that the Stagirite upheld (B) we might answer the questions, (I) "What, according to Aristotle, is the function of an efficient cause?" and (2) "What, generally speaking, is an efficient cause the efficient cause of for Aristotle?" To answer the first question, we shall find, is automatically to answer the second question. Aristotle identifies an efficient cause with the agent in any change or coming-to-be. In his formal definition of the four causes in the Physics he equates an efficient cause with the source of change or coming to rest.2 And the examples of efficient causes he gives there (or elsewhere) are agents in a change. The man who gives advice is the efficient cause of some change in the advisee, and the father is the efficient cause of the child. In general, he says, efficient causes are " What makes of what is made and what causes change in what is changed." From this definition alone it is clear that Aristotle views an efficient cause, as he views each of the other three types of causes, as a necessary factor in the explanation of change or becoming. If there is to be becoming at all, Aristotle commonsensically insists, there must not only be something which comes into being and something which becomes it, i.e., form and matter respectively, but also something which, by working on the matter, makes a certain form come to be out of the matter. Thus, by working on the building materials the builder makes the form of a house come to be out of this material. Nor is it sufficient to define an efficient cause simply as that which actualizes a given potentiality in a thing. For while it is true that the builder qua building is actualizing the form of a house which exists in a potential way in the building materials, still, the potentiality of the builder to build is itself actualized by the final cause according to Aristotle.3 In • See Physics, 194b 11. fl9-81. • Aristotle holds that the final cause is the cause of the causality of the efficient cause...