See the whole doctrine in Aristotle de Ánim, where the θρεπτικὴ ψυχὴ is treated as exactly equivalent to θρεπτικὴ δύναμις.
It deserves notice that the parts of nature which Aristotle regards as representing evidence of design, are the Uniformities: the phenomena in so far as reducible to law. Τύχη and τὸ αὐτομάτον satisfy him as explanations of the variable element in phenomena, but their occurring according to a fixed rule can only, to his conceptions, be accounted for by an Intelligent Will. The common, or what may be called the instinctive, religious interpretation of nature, is the reverse of this. The events in which men spontaneously see the hand of a supernatural being, are those which can not, as they think, be reduced to a physical law. What they can distinctly connect with physical causes, and especially what they can predict, though of course ascribed to an Author of Nature, if they already recognize such an author, might be conceived, they think, to arise from a blind fatality, and in any case do not appear to them to bear so obviously the mark of a divine will. And this distinction has been countenanced by eminent writers on Natural Theology, in particular by Dr. Chalmers, who thinks that though design is present everywhere, the irresistible evidence of it is to be found not in the laws of nature but in the collocations, i.e., in the part of nature in which it is impossible to trace any law.
A few properties of dead matter might, he thinks, conceivably account for the regular and invariable succession of effects and causes; but that the different kinds of matter have been so placed as to promote beneficent ends, is what he regards as the proof of a Divine Providence. Mr. Baden Powell, in his Essay entitled “Philosophy of Creation,” has returned to the point of view of Aristotle and the ancients, and vigorously re-asserts the doctrine that the indication of design in the universe is not special adaptations, but Uniformity and Law, these being the evidences of mind, and not what appears to us to be a provision for our uses. While I decline to express any opinion here on this vexata quæstio, I ought not to mention Mr. Powell’s volume without the acknowledgment due to the philosophic spirit which pervades generally the three Essays composing it, forming in the case of one of them (the “Unity of Worlds”) an honorable contrast with the other dissertations, so far as they have come under my notice, which have appeared on either side of that controversy.
In the words of Fontenelle, another celebrated Cartesian, “les philosophes aussi bien que le peuple avaient cru que l’me et le corps agissaient réellement et physiquement l’un sur l’autre. Descartes vint, qui prouva que leur nature ne permettait point cette sorte de communication véritable, et qu’ils n’en pouvaient avoir qu’une apparente, dont Dieu était le Médiateur.”—(Œuvres de Fontenelle, ed. 1767, tom. v., p. 534.)
Chapter VI. On The Composition Of Causes.
I omit, for simplicity, to take into account the effect, in this latter case, of the diminution of pressure, in diminishing the flow of water through the drain; which evidently in no way affects the truth or applicability of the principle, since when the two causes act simultaneously the conditions of that diminution of pressure do not arise.