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 CAUSE

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CAUSE

He holds that the world is eternal; but, in virtue of his fundamental principle that no potentiality can pre- cede actuality, he makes it a participative eternity. Hence the material and the formal causes that together go to make up the world are created, or more properly, eternally concreated. From this funda- mental principle of the priority of actuality over potentiality. Aristotle proves also t ho fact "of the existence of God as the first moving cause. As each effect of a process is now to be reckoned an actuality that was before no more than potential, and postu- lates a moving cause in order that it should have come into being as the term of a motion, so all things in the world, taken together, necessitate an absolutely first cause of the same nature. This first moving cause must, on Aristotle's principle, be an absolute actual- ity, since, were it not entirely in act, it could not be t he moving cause of all t lungs nor keep them eternally in motion. Similarly, it must be pure form, or poOs, with no admixture of matter, since this would import a limitation of its actuality. Thus did Aristotle raise and answer the question of causality, dividing causes into four classes, and indicating the nature of the causal influx with which each contributes towards the production of their common effect. For, according to this theory, all tiie four causes, taken together, are really the cause of any given physical effect.

The teaching of Aristotle is that which substan- tially passed current in the medieval schools. With certain important modifications concerning the eternity of the material cause, the substantiality of certain formal causes of material entities, and* the determination of the final cause, the fourfold division was handed on to the Christian teachers of patristic and scholastic times. As Aristotle had developed and improved the doctrine of Plato with regard to inherent substantial forms, so the leaders of Christian thought, guided in their work by the light of revelation and the teaching of the Church, perfected the philosophical teaching of Aristotle. It is not. indeed, advanced that the Christian philosophy of this period was merely theological; but it is contended that certain purely philosophical truths, verifiable in and by philosophy, were obtained as a result of the impetus given to meta- physical research by the dogmas of revelation. This is not the place for enlarging upon such a topic except in so far as it is directly pertinent to the question of causes; anil it is principally in other matters that the contention obtains. Still, at least in the three cases to which allusion has just been made, it is true that speculation was helped forward on the right lines by the teaching of the Church. The truth of the con- tention is patent. In the patristic period, particu- larly in the works of St. Augustine, who was a Plato- nist rather than an Aristotelean, and in the scholastic Period, the foremost representative of which is St. Thomas Aquinas, the doctrine of the four causes of being is set forth in connexion with t he modifications noted. The theory of causality, as held and taught in the Middle Ages, and as taught in the schools to-day, will in this section be exhibited in some detail.

"The ancient philosophers came to the knowledge of truth by degrees and slowly ", writes St. Thomas. " For at first, being as it were less cultivated, they did not recognize any beings other than sensible bodies. And those of them who acknowledged movement in them only admitted movement as to accidents, as in rarity and density, aggregation and disgregation. And, supposing that the substance of bodies was uncreated, they assigned certain causes for accidental changesof this kind, as, forexample, friendship, strife, intellect .or something of this nature. Proceeding, they distinguished intellectually between the substantial form and the matter, which they considered as un- created; and they perceived that substantial transmu- tation takes place in bodies with respect to their sub- stantial forms." (SummaTheologica, Q. xliv, a. 1,2.)

The last sentence of this passage gives the basis of the Scholastic doctrine with regard to causes. "Consider", a Scholastic would say, "a substantial change — that is to say, a change in which one sub- stance, made known to the understanding by its qualities, ceases to be what it was in the instant A, and becomes, in the instant B, another substance. In order that such a change should be possible, four things are necessary: namely, (1) the thing that is changed; (2) the term, or manner of being, or essence, that is induced in that which is changed; (3) the active agent that produces the change, or accom- plishes the existence of the new term, manner of being, or essence; and (4) the motive, or reason why this latter acts. There is also, though it cannot be reckoned as a cause, the terminus a quo, or the original determinative of the thing changed, which passes out of being with the advent of the newly induced term. These four necessary things, since they produce the final result by a mutual action and interaction, in which they give being to it considered as result, arc its causes. They are to be discovered, moreover, wher- ever and whenever any change takes place, not only in substantial, but also in accidental, changes, or mere changes of qualities." Consider the two cases, the one of accidental, the other of substantial, change. A cube of wax is moulded by the hand into a sphere. The wax, as permanent substratum of the change of figure, is considered to be the matter, or material cause. The spherical figure supervening upon that of the cubical, is the induced formal cause. The moulder, or fashioner of the sphere, is the efficient cause. The final cause is to be sought for in the inten- tion of the moulder. The substance of the wax remains throughout the entire process of the mould- ing. It is affected only accidentally by the operation. Consequently the example is one of accidental change, and gives us no more than an accidental formal cause. But in cases of substantial change, such as, for example, the electrolysis of water, the induced formal cause is a substantial one; and, more- over, since the substance of the water does not remain after the change has taken place, the material cause cannot be other than a subject, or permanent substratum, that is neither water nor oxygen and hydrogen taken together. In such a case, it is called primordial, or first matter, and is conceived as being a subject potential to information by any and all formal causes. It is a potentiality, but. as a perma- nent substratum, or determinable entity, is capable of receiving new substantial determinations in the place of that which actually denominates it. It cannot exist alone, but exists only as informed, or actuated by a formal cause. It is no! eternal, but created, or, more properly, concreated with substan- tial form.

The material cause, as presented in the Scholastic system of philosophy, fulfils the conditions of a cause as given above. It gives being to the effect, since without it this could neither exist nor come into be- ing. Though it is conceived a> an essentially incom- plete subject, as a merely passive potentiality, it is distinguished from the complete effect, to the be- coming and being of which it contributes. The diversity of primordial matter from the forms which actuate it is exhibited by the consideration that there is an essential distinction between the subject of change and the states, modifications, or determined natures from which and towards which the change is conceived as acting. Hence primordial matter is reasonably held to be a reality, belonging reduc- tively to the category of substance, and determinable to even- kind of corporeal substance by reason of its essential ordination to the reception of a form. Quantity is said to be a coneequenl of material sub- stances by reason of the matter entering into their physical composition; and by matter, as quantified,