XI.

WHY THE PHYSICAL SYSTEM IS SO CALLED.

WHY (it may be asked) is this system to be called the Physical System, and not the Scholastic System, or the System of Matter and Form?

We cannot call it Scholastic, In the first place that name would not indicate its nature, but only its history; and historically it should rather be called Aristotelian or Peripatetic. Secondly it is well, known that, although the Scholastics, generally speaking, agreed about the principal points of philosophy, they differed not a little on other points, especially after Luther had brought into contempt, with the teaching of St. Thomas and Aristotle, not only scholastic Theology but scholastic philosophy also and Descartes had set himself, by means of a little mechanical motion, to infuse new life into the dead and forgotten system of Epicurus. A man professing himself to be a scholastic may be accused of all the opinions put forth as scholastic of any sort, even in the experimental order, for the purpose of refuting and ridiculing and raising wearisome controversies. Thirdly, some people would carry the dispute from philosophy into history, trying to show that the system here defended was wrongly ascribed to the scholastics. Altogether the name would be unadviseable.

Shall we call it then the system of Matter and Form, or of Materialism and Formalism, as including the Mechanic and Dynamic systems, to each of which belongs one of those names? By no means. The Mechanic System is not strictly a system of Materialism; for that Consists in negation of Forms, and has as many degrees as there are degrees of forms. In the first degree form is denied of inanimate substances. In the second it is denied of vegetating things. In the third it is denied of brutes. In the fourth it is denied of man. That system only which admits in all nature nothing more than matter and mechanical motion is absolute Materialism but a very great number of those who profess the Mechanic system are a long way from that, though the passage from one degree to the other is not difficult.

Descartes himself and his most faithful disciples never went beyond the third degree, turning brutes into machines. His recent followers restrict their denial of form to plants, which they take to be machines, and to things without life, which they suppose to consist in a collection of inert atoms. Moreover materia prima, as we have shown, is quite different from the said atoms. As to the dynamic system, what have its forces to do with substantial forms? Those forces are supposed to subsist in mathematical points, whereas substantial forms make corporeal substances, representing, in various ways, the Divine archetypal ideas; and are not in mathematical points, but in extended matter informed. Since then materia prima is not a principle admitted by the Mechanic system, nor is Form admitted by the Dynamic system, consequently the Physical system cannot be the union of the two. Some have said, when treating of the Physical system, that the Physical Sciences, not satisfied with what is given to them by the one or the other of the above mentioned systems, require what is given by both together. But this they said, considering the thing in the abstract and by analogy, not in the concrete and properly for the physical sciences, demanding a principle of extension and a principle of activity, are not to be satisfied with inert atoms and mere forces. Therefore the Physical system, as here explained, cannot be called a system of either Materialism or Formalism, but requires a more appropriate name of its own.

"Anyhow," it will be said, "you have no right to call it Physical. By giving it that name you affirm it to be requisite for the natural sciences commonly called physical, and you exclude all the others invented and defended by philosophers." But we cannot help excluding them. We have shown that Mechanic and Dynamic are names not suitable to the Physical Sciences; and therefore, since all the other systems are reducible to the Mechanic and Dynamic, the system that we are defending has a right to be called the Physical system.

Moreover that name marks the essence of the thing meant, and thus distinguishes it clearly from every other. For the word phusikos means natural: and the word nature means the sum of corporeal substances as having an inner principle of operation. Therefore those inner principles, which the corporeal substances have, are called physical or natural laws. But, as we said before, a corporeal substance is called a nature, because matter is therein united to a substantial form which is its first principle of operation: and therefore the name of "Physical" serves to point out that the system, so called, requires in substances the two-fold principle, material and formal, which constitutes the essence of the same.

"According to the Philosopher," (V. Metaph.) says St. Thomas, "the word nature was first given to signify the generation of living things, which is called birth. And, because such generation is from an intrinsic principle, the name was further understood to mean the inner principle of every motion whatsoever. And so is nature defined in the second Book of Physics. And because this principle is both formal and material, both the matter and the form are commonly called the nature of the thing. And because the essence of everything whatsoever is completed by the form, the essence, which is signified by the definition, is commonly called its nature."^{1}

The word Physical then, marks what is proper to the system before us, distinguishing it essentially from every other: and therefore that name is appropriately given to it. In the next chapter we shall have to consider the system relatively.

{1} P. i. Q xxix. a. 1 ad 4.