The Origins of the Problem of the Unity of Form

THE ORIGINS OF THE PROBLEM OF THE UNITY OF FORM T HE philosophical problem with which we are here concerned may briefly be formulated thus: Whether in one and the same: individual, remaining essentially one, there are many substantial forms or only one. A concrete thing of matter and form, the crvvoA.ov, is one essence and one nature, but it possesses several perfections and activities. It is, in fact, a body, corpus, and it is such and such a body, a stone or a tree or a horse. A tree is a body, but it is a determinate body, quite different from a stone or a horse; besides being a corporeal thing, it is also a living thing. Now, as Boethius has it, it is the form that confers on matter the actual being: omne esse ex forma est.1 A substantial form imparts an essential perfection, and an accidental form a relative or qualified perfection. Assuming that substantial form is the determining principle of a composite being, the difficulty arises of how to account for the various essential perfections of an individual. Does one substantial form give one perfection only, so that we have to look for as many substantial forms as there are perfections and activities; or does a single form suffice to determine the thing in its own nature, thus endowing it with all its perfections and activities? A stone is a corporeal thing as much as a piece of iron, and man is as much a living being as a tree or a horse; but as a horse possesses some perfections which a tree has not, for example, sensitive life, so man, besides having nutritive and sense powers, is also endowed with an intellective soul. The whole point of the discussion, therefore, comes to this: Is a man-let us say man, for it was in connection with the human soul that the vexed question was first stated-a living 1 Boethius, De trinitate, c. 2 (The Theological Tractates, ed. H. F. Stewart and E. K. Rand. London, 1926, p. 8; PL 64, 1250 B). 257 258 DANIEL A. CALLUS being by virtue of a distinct nutritive soul, an animal through a distinct sensitive soul, and finally rational by an intellective soul; or does he owe to one single substantial form, the intellective soul, not only his being a man, or rational, but also his being an animal, a living thing, and a corporal substance? If with Aristotle one holds (i) that prime matter is a completely passive potency without any actuality of its own whatever ; (ii) that privation is the disappearance of the previous form, and, consequently, has no part at all in the composition of the substance; and (iii) that substantial form is absolutely the first determining principle, which makes the thing to be what it is, the only root of actuality, unity and perfection of the thing; then, consistent with his stated principles, the conclusion forced upon us is that in one and the same individual there can be but one single substantial form: other forms, that come after the first, are simply accidental and not substantial forms. Since the thing is already constituted in its own being, they cannot give substantial being, but exclusively accidental or qualified being; they do not confer upon the concrete thing its own definite and specific kind of being, e. g., man, but only a qualified or relative state of being, for example, of being fair or dark, big or small, and the like. On the other hand, if one contends (i) that primary matter is not absolutely passive and potential, but possesses in itself some actuality, no matter how incomplete or imperfect it may be: an incohatio formae, or any active power; (ii) that privation does not mean the complete disappearance of the previous form, so that matter is not stripped of all precedent forms in the process of becoming; or (iii) that substantial form either meets with some actuality in prime matter or does not determine the composite wholly and entirely, but only partially; from all this it will necessarily follow that there are in one and the same individual plurality of forms. Briefly...