The Notion of Efficient Cause in the Secunda Via

THE NOTION OF EFFICIENT CAUSE IN THE SECUNDA VIA MUCH OF THE literature on Thomas's secunda via, both that produced by his friends and that produced by his enemies, seems to proceed on the assumption that " efficient cause " is for Thomas a univocal notion and one that is ~asily grasped. A close reading of the texts, however, reveals that it is, on the contrary, a quite complex sort of idea involving some very precise distinctions which the unwary reader is apt to overlook. In the fifth book of his Commentary on the Metaphysics, St. Thomas notes, with apparent approvaV that Avicenna distinguished four modes of efficient causality: perficiens, disponens , adjuvans, and consilians.2 The perfecting cause is that which effects the ultimate perfection, that which induces (inducit ) the substantial form in natural things or the artificial form in artifacts. The disposing cause 3 is that which does not itself induce the form which is the end of the action but only prepares the matter which is to receive the form.4 The assisting cause is one which acts, not for its own end, in producing a form but for the end of the principal cause, as one who aids the king in battle acts for the king's purpose. 1 That he does approve Avicenna's analysis is evident from the fact that he uses it in his Commentary on the Physics, Book II, lect. 5, without qualifying it as being the interpretation of another. 2 Expositio in Metaphysicorum, lib. 5, lect. ~. 3 In his commentary on the second book of the Physics, Thomas calls this the causa praeparans. • St. Thomas cites as an example of a disposing cause one who hews wood and stone for a house. Such a cause, however, is not properly said to be an efficient cause with respect to the house; but, if the disposing cause induces into the matter the ultimate disposition upon which the form necessarily follows, then magis tamen proprie erit efjiciens. It is as a disposing cause, Thomas says, that man generates his offspring. V Meta., lect. ~. 754 EFFICIENT CAUSE IN THE" SECUNDA VIA" 755 This last mode, adjuvans, is the disposition a secondary cause has to a first cause, for secondary causes in any per se order of causes always act for the end of the first in the order. A counseling cause, finally, supplies the .end and form of the action to be performed.5 Such is the bearing of the first agent per intellecturn to every secondary agent, for the first intelligent efficient cause in any per se series supplies to all in the series the end and form of the action, just as the architect of a ship supplies the end and the form of the action to those who build the ship. To these four modes of causality, Thomas continues, one can reduce everything which makes something to be in some way (quicquid facit aliquid quocumque modo esse) ,6 whether this be according to the substantial esse of a thing or according to its accidental esse, as is the case in all motion. Not only, therefore, is that which makes something a cause of what is made (esse substantiale), but also whatever changes another is the cause of the changed being (esse accidentale) . Any or all of these four modes, then, may enter into our definition of efficient cause. In the Summa theologiaes when St. Thomas treats of God as efficient cause of the universe, he does not begin, as a theologian is entitled to begin, with the biblical account of creation . Rather, he begins with what is sensible and intelligible in the universe, analyses it in light of certain metaphysical principles, and concludes to the existence of a first efficient cause, quam omnes Deum nominant.7 This secunda via, expounded so summarily in the second question of the Summa, can be broken down into a number of propositions, each of which must be investigated thoroughly if the cogency of the argument is to be examined: (1) In sensible things there is an order of efficient causes. (2) It is impossible that this order of efficient causes should preceed to infinity. (8) There must • Cf...