Substantial change (Lat. generatio simpliciter ) or absolute becoming (Lat. fieri absolute, fieri simpliciter ) is the passage in a subject from absolute nonbeing to being that is substance. This passage is necessarily produced in the indivisible instant in which a substance both comes to be and exists in itself. For example, when Socrates becomes man, in contrast to his becoming pale or suntanned, there is no time or instant in which Socrates himself begins to exist and yet does not already exist. As a substance, he does not admit of being more or less. He can, however, be more or less pale or suntanned, and become so through a becoming that, unlike substantial change, is motion in the strict sense, successive and measured by time. Because substantial change is a change between contradictories (being and nonbeing), wherein there is no intermediary, it is not simply a change according to place, or according to quality, or according to quantity, or merely some combination of these. Such changes affect an already existing substance only in some respect and not absolutely. There is always, however, a motion in the strict sense that precedes the instantaneous generation of a substance and terminates at the moment of generation. And in every substantial change there is involved not only the absolute generation of a substance that did not exist before, but also the absolute corruption of a substance that did exist before. The change of quality of this preceding composite of subject and substantial form, called alteration, terminates (1) at an ultimate qualitative disposition incompatible with the preceding substance,(2) at the corruption of this substance, and (3) at the production of the substance that now comes to be absolutely—and terminates at all three in the same instant.
Terminological Distinctions. The following distinctions of meaning in the use of the expression "absolute becoming" are indispensable for understanding substantial change, for sometimes the word "absolute" refers to the becoming itself, sometimes to the term of the becoming, and sometimes to both.
"Absolute becoming" can mean: (1) becoming in the strict sense, which is a motion, measured by time, such as "being in the process of whitening"; (2) becoming, again in the strict sense, but attributed to a substance, such as Socrates, as to its term but before this term is attained; (3) becoming that is according to contradictories and therefore instantaneous, whether in the order of acci dent or that of substance; (4) the becoming of a substance, such as Socrates, where the term signifies both the alteration that precedes Socrates and his instantaneous becoming; or (5) the instantaneous becoming of an absolute being, which is called "becoming" with respect to the preceding movement of alteration, and "absolute" by reason of that which comes to be, namely a being absolutely or a substance.
The permanent subject required for becoming as such—something that the earliest philosophers acknowledged—is called matter, by analogy with that "from which" and "out of which" artificial objects are made, as a table is made out of wood, and is regarded as a potency in relation to the act or form acquired in becoming. This subject, common to both terms of the becoming and permanent throughout it, must be part of the substance generated, and must have been part of the substance now corrupted. This is necessary if the substance now generated, say Socrates, is truly to have come to be according to what he is absolutely, and is not merely to have become pale or suntanned, either of which requires that he himself already have come to be and, now existing, can become this or that.
Greek Problematic. The difficulty of accounting for the difference between substantial change and accidental change, and of accounting for the sensibly evident multiplicity and variety of things in the world and the unity and unchangeableness that things have in the mind, finds its first expression in ancient Greece. The pre-Socratic philosophers puzzled over the problem of the one and the many, seeking to account for changes in a way that yet allowed for unchanging knowledge. Driven to extreme positions in their quest for a truth that proved unexpectedly difficult, some, like parmenides of Elea (515–440 b.c.), argued that true knowledge and science must be possible, that only being that is one is real, but that change is an illusion. Others, like Cratylus of Ephesus (5th century b.c.), a disciple of heraclitus the Obscure (530–470 b.c.), argued that being was the illusion, change the only reality, and hence true knowledge and science were impossible. Further attempts to reconcile these extreme views proved unsatisfactory. The skepticism of the sophists finally provoked a sincere new effort to resolve the dilemma and preserve the truths already attained.
Socrates's arguments with the Sophists and Plato's further development of theory and reflective thinking prepared the way for a flowering of logic in the thought of Aristotle. Aristotle's solution was that there is a permanent subject of the forms that succeed each other in change, and that this subject is a potency that lacks at first the form of the composite produced at the end of the change. In substantial change, the subject must be a pure potency in itself lacking any form, but able to be the subject of any form it lacks. A substance, then, does not come to be from sheer nothing, but from being in potency (not being in act). It thus becomes possible to have true knowledge and science even of changeable things by knowing their necessary principles, causes, and elements; material individuals themselves, however, are known in sensation and remain perishable in time.
Although Aristotle's solution to the problem of being and becoming is conclusive, it is by no means a conclusion of man's perennial pursuit of wisdom to satisfy his wonder. Nor do later philosophers always accept it as the foundation of further research and explanation.
Medieval and Modern Thought. In the Middle Ages, Aristotle's most famous commentator, St. thomas aquinas, imparted a new momentum to the reintroduction of Aristotle's teachings into the stream of Western thought. He affirmed again the dependence of knowledge in the order of learning on experience of the sensible world, reiterated the principles enunciated by Aristotle, and elaborated upon them in arguing against the Platonist view of reality that placed the primary emphasis on a priori forms of human thought. The ancient dilemma of being and becoming, of the noetic problem of the one and the many, found further controversial expression in the rationalistic thought of descartes and his followers in the rise of British empiricism. Kant's critical idealism sought anew to resolve the same basic problem by distinguishing between things in themselves and their "appearances in sensuous representation" or a priori intellectual formation. The Platonist view persevered, only to be countered by continued insistence from empiricists upon the reality of changing phenomena to the exclusion of intellectual certainty.
The German idealist philosopher, hegel, meditating on the paradox of instantaneous becoming and substantial change, denied that it was a paradox, and affirmed the identity of being or substance in thought with its contradictory opposite, nonbeing or nothing. He regarded the very antithesis of reason as the only reasonable principle to hold; contradiction itself was the source of all being and becoming.
Problems from Modern Science. The rapid development of natural science and experimental method, of modern physics and atomic theory, presented new difficulties. Real substantial differences and substantial changes in the world first seemed to give way to differences merely in atomic or nuclear structure of basically unchanging but rearrangeable fundamental particles. But these protons, electrons, neutrons, and other newly discovered or manufactured particles themselves soon exhibited the capacity to be transformed.
Nuclear isomerism, which refers to atomic nuclei with the same mass and charge but with different nuclear properties such as observably different half-lives, pointed to differences between isomers of the same element that might qualify as "accidental" in terms of Aristotelian principles. The destruction of chemical bonds between molecular atoms due to isomeric transitions characterized by energy emission, or to other radioactive transformations, pointed to changes that might be "substantial" or "accidental." But to think of such changes as occurring on the microscopic level of the atomic and subatomic worlds, where unimaginable waves and particles dissolve one into the other, leads to the use of ambiguous and misleading language. Ordinary terminology becomes equivocal when thus transferred to the context of modern physics and chemistry.
In their employment of measurement to get at the quantitative aspects of things, and in their mathematical formulation of results, the concrete branches of modern science necessarily abstract from the basic problem and its solution. However important are the problems the experimental sciences attempt to resolve, the philosophical problem of substantial change lies outside the scope of their direct concern. And whether physical substances are made of protons and electrons or of the elements of the ancients, perennial philosophy still regards substances as capable of coming to be from being in potency, and not from being in act, and as existing in themselves and not in something else. It holds, moreover, that some certain knowledge of their nature and properties can be had in terms of their necessary principles, causes, and elements.
See Also: atomism; hylomorphism; hylosystemism; matter and form.
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