Modern Physics and Hylomorphism

If modern physics reveals anything, it is that the old atomism is dead. Physicists have begun to realize that we just can't explain things in a reductionistic way anymore. Modern physics has actually helped to "de-materialize" the material world. If by matter we think of extension, then it can be said that the material world is more immaterial than material. It is the immaterial principle that makes a thing to be what it is, not little atomic billiard balls. To really understand this, we have to learn to disregard our imagination. We cannot "picture" potency and act, and so we cannot "picture" the ultimate constitution of matter. We have to learn to "think" these principles. Modern physics tends to support this hylomorphic requirement. Let me quote Heisenberg rather extensively. He writes:

What is an elementary particle? We say, for instance, simply "a neutron" but we can give no well-defined picture and what we mean by the word. We can use several pictures and describe it once as a particle, once as a wave or as a wave packet. But we know that none of these descriptions is accurate. Certainly the neutron has no color, no smell, no taste. In this respect it resembles the atom of Greek philosophy. But even the other qualities are taken from the elementary particle, at least to some extent; the concepts of geometry and kinematics, like shape or motion in space, cannot be applied to it consistently. If one wants to give an accurate description of the elementary particle--and here the emphasis is on the word "accurate"--the only thing which can be written down as description is a probability function. But then one sees that not even the quality of being (if that may be called a "quality") belongs to what is described. It is a possibility for being or a tendency for being. Therefore, the elementary particle of modern physics is still far more abstract than the atom of the Greeks, and it is by this very property more consistent as a clue for explaining the behavior of matter.[1]

The term "quality of being" should not be taken too literally. It is likely that he employs this term to refer to some concrete "thing" that can be measured. But a tendency for being, or potentiality, is not nothing. Concerning this potentiality, Heisenberg writes:

Besides the three fundamental building stones of matter - electron, proton, and neutron - new elementary particles have been found which can be created in these processes of highest energies and disappear again after a short time. The new particles have similar properties as the old ones except for their instability. Even the most stable ones have lifetimes of roughly only a millionth part of a second, and the lifetimes of others are even a thousand times smaller....

These results seem at first sight to lead away from the idea of the unity of matter, since the number of fundamental units of matter seems to have again increased to values comparable to the number of different chemical elements. But this would not be a proper interpretation. The experiments have at the same time shown that the particles can be created from other particles or simply from the kinetic energy of such particles, and they can again disintegrate into other particles. Actually the experiments have shown the complete mutability of matter. All the elementary particles can, at sufficiently high energies, be transmuted into other particles, or they can simply be created from kinetic energy and can be annihilated into energy, for instance, into radiation. Therefore, we have here actually the final proof for the unity of matter. All the elementary particles are made of the same substance (see end for comment on this term), which we may call energy or universal matter; they are just different forms in which matter can appear.

If we compare this situation with the Aristotelian concepts of matter and form, we can say that the matter of Aristotle, which is mere "potentia", should be compared to our concept of energy, which gets into "actuality" by means of the form, when the elementary particle is created.

Modern physics is of course not satisfied with only qualitative description of the fundamental structure of matter; it must try on the basis of careful experimental investigations to get a mathematical formulation of those natural laws that determine the "forms" of matter, the elementary particles and their forces (note: the elementary particles don't do the "forming"). A clear distinction between matter and force can no longer be made in this part of physics, since each elementary particle not only is producing some forces and is acted upon by forces, but it is at the same time representing a certain field of force. The quantum-theoretical dualism of waves and particles makes the same entity appear both as matter and as force....[2]

We should not take his use of the word "substance" too literally when he maintains that "all elementary particles are made of the same substance". In Aristotelian thinking, potency is not substance, but the potential principle of substance. If "universal matter" corresponds to Aristotle's prime matter or "potentia", as Heisenberg suggests, then we have to remember that universal matter is not substance but "substratum".[3]

In a similar way in quantum theory all the classical concepts are, when applied to the atom, just as well and just as little defined as the "temperature of the atom"; they are correlated with statistical expectations; only in rare cases may the expectation become the equivalent of certainty. Again, as in classical thermodynamics, it is difficult to call the expectation objective. One might perhaps call it an objective tendency or possibility, a "potentia in the sense of Aristotelian philosophy. In fact, I believe that the language actually used by physicists when they speak about atomic events produces in their minds similar notions as the concept "potentia". So the physicists have gradually become accustomed to considering the electronic orbits, etc., not a reality but rather as a kind of "potentia". The language has already adjusted itself, at least to some extent, to this true situation. But it is not a precise language in which one could use the normal logical patterns; it is a language that produces pictures in our minds, but together with them the notion that the pictures have only a vague connection with reality, that they represent only a tendency toward reality (emphasis mine).[4]

In the experiments about atomic events we have to do with things and facts, with phenomena that are just as real as any phenomena in daily life. But the atoms or the elementary particles themselves are not as real; they form a world of potentialities or possibilities rather than one of things or facts.[5]

Now "potentia", in the Aristotelian framework, is entirely real. It is real only as realized by act or form. It cannot exist apart from form; for then it would be actually nothing. It cannot exist independent of form anymore than a block of wood could exist independent of an accidental shape. Form realizes, that is, makes real or actualizes prime matter. Also, when atoms belong to a higher unity, such as water, or an even higher unity such as a plant or animal, the prime matter is not to be conceived of as the prime matter of the atoms. The atoms of the elements have changed, that is, they have ceased to be "what they are" (contrary to Empedocles). They have transformed. The plant is one thing, not many atoms. In the plant, the elements have become living. The atoms of the various elements no longer behave in the same way. They act differently, and so they are different. They belong to a higher form. They have become parts of a unified living organism (in this case, a plant). The prime matter is that of the plant as a whole. The plant as a whole is a composite of potency and act, or matter and form. In the plant, the oxygen atom, for example, has transformed. It's prime matter has acquired another form, namely that of the plant. It has ceased to be oxygen (an inanimate element) and is now only virtually present in the plant.

¹Werner Heisenberg, Physics and Philosophy. The Revolution in Modern Science (New York: Harper, 1962), 70.

⁴Physics and Philosophy, 180-81. Cf. Nick Herbert Quantum Reality, 40, 90, 124. "But matter is unknowable of itself." Aristotle, Metaph., Z 10,1036a8-9. "--all things produced either by nature or art have matter; for each of them is capable both of being and of not being, and this capacity is matter in each." Z 7,1032a20-22. Oxford trans. See also Q 7, 1049a27-28.