Aristotle's Metaphysics

Form, Matter and Identity

Jeremy Kirby

• Publisher: Continuum
• Year: 2011
• Print ISBN: 9781441154613
• eBook ISBN: 9781441101990
• Edition: 1
• Topic: Philosophy
• Subtopic: Ancient & Classical Philosophy

Aristotle maintains that biological organisms are compounds of matter and form and that compounds that have the same form are individuated by their matter. According to Aristotle, an object that undergoes change is an object that undergoes a change in form, i.e. form is imposed upon something material in nature. Aristotle therefore identifies organisms according to their matter and essential forms, forms that are arguably essential to an object's existence.
Jeremy Kirby addresses a difficulty in Aristotle's metaphysics, namely the possibility that two organisms of the same species might share the same matter. If they share the same form, as Aristotle seems to suggest, then they seem to share that which they cannot, their identity. By taking into account Aristotle's views on the soul, its relation to living matter, and his rejection of the possibility of resurrection, Kirby reconstructs an answer to this problem and shows how Aristotle relies on some of the central themes in his system in order to resist this unwelcome result that his metaphysics might suggest.

Chapter 1
Matters of Individuation

Matters of Change

In the Physics, I.7, Aristotle attempts to steer a middle course between two unwelcome alternatives: either that which comes to be comes to be from being, and, thus, already is, or, that which comes to be comes to be out of nonbeing. Aristotle’s approach to this difficulty involves a distinction between form and matter. We can explain how a statue comes into existence by noticing that at one point in time the sculptor has a mere lump of material with which to work. When the work has been completed, a form has been imposed upon the sculptor’s material. The lump of clay undergoes the transition from not being a statue, while lacking the form, to the state of being a statue, once the work of the artist is complete. Consider, then, the fifth premise of the Eleatic Puzzle:

(5) If it comes to be from what is not, then it comes to be from nothing.

One might interpret Aristotle as maintaining that the premise is ambiguous between two interpretations:

(5a) If it comes to be from what is not such-and-such, then it comes to be from nothing.

(5b) If it comes to be from what is not in existence, then it comes to be from nothing.

The latter premise amounts to very little. If we assume that our candidate for change will come to be from what is not in existence, and what is not in existence is nothing, then (5b) simply says that whatever comes into being from nothing comes into being from nothing. The former premise, while a little less vacuous, appears, however, to be false. For we might take, in the antecedent of this conditional, the term “it” to refer to a statue of Percales. And we may suppose that the statue comes to be such-and-such a statue from a mere lump of bronze, which, needless to say, is not such-and-such. But this is not to say that the statue comes to be from nothing. On the contrary, the lump of bronze is something (191a7–12):

The underlying nature can be known by an analogy. For as the bronze is to the statue, the wood to the bed, or the matter and the formless before receiving form to anything which has form, so is the underlying nature to substance, i.e. the “this” or existent.

In this same way, Aristotle is led to analyze those substances with which he is most concerned: biological organisms (190a31–b5):

Things are said to come to be in different ways. In some cases we do not use the expression “come to be”, but “come to be so-and-so”. Only substances are said to come to be without qualification. Now in all cases other than substance it is plain that there must be something underlying, namely, that which becomes. For when a thing comes to be of such a quantity or quality or in such a relation, time, or place, a subject is always presupposed, since substance alone is not predicated of another subject, but everything else of substance. But that substances too, and anything that can be said to be without qualification, come to be from some underlying thing, will appear on examination. For we find in every case something that underlies from which proceeds that which comes to be; for instance, animals and plants from seed.

Thus, Aristotle’s use of matter, as substrate, and form, as a way that the substrate is modified, plays an integral role in his analysis of change. Indeed, Aristotle’s technical term for matter, hulê, does not appear in the works that are typically thought to precede the Physics. And, for this reason, some scholars believe that Aristotle includes matter in his ontology as a result of his having grappled with the analysis of change.

Matters of Difference

Matter, however, seems to account for more than that which underlies change. On the traditional view, Aristotle also believes that matter accounts for numerical difference. In the Metaphysics, VII.8, he maintains that two organisms of the same species will be compounds of matter and form, which are different in virtue of their matter, but the same in terms of their form. Aristotle’s comments here, and elsewhere, have suggested to some scholars that he takes matter to be a principium individuationis, or a principle of individuation. Other scholars, however, are weary of the interpretive costs of attributing this view to Aristotle.

A fair amount hinges on this exegetical issue. For if Aristotle does not take matter to be that which is responsible for the numerical difference that obtains between Socrates and Callias, then it would seem that we may jettison HI:

HI Hylo-Difference: Cospecific substances are numerically
different in virtue of their matter.

Having done so, the Puzzle of Composition might be sidestepped. If matter is not that which is responsible for the numerical difference of Socrates and Callias, one might wonder why SH, the claim that organisms are to be identified with their matter and form, ought to be accepted. For if the form of Socrates and Callias really is numerically identical, one cannot hope to identify Socrates with his form, as one might as easily, thereby, identify Callias. (We will later consider the merits of denying that the form in question is a universal.) In this way, the matter of Socrates and Callias would seem to be the only means for providing the requisite uniqueness for identifying organisms with their matter and form. Of course, one might be willing to part ways with SH as well, but then it seems unclear what Aristotle’s hylomorphism amounts to. Furthermore, if matter is to be considered the principle of individuation, this is prima facie evidence for thinking that Aristotle might reject HM, the claim that the matter of one substance may become that of another. For if matter, in some sense of the term, is that which really individuates Socrates and Callias, then the matter of one could not become the matter of the other.

Identity, Diversity, and Unity

Individuation and predication

One might think of the following text, from Metaphysics V.6, as fairly supportive of the view that Aristotle does think of matter as the principle of individuation (1016b32–5):

Again some things are one in number (eti de ta men kat’ arithmon estin hen), others in species (ta de kat’ eidos), others in genus (ta de kata genos), others by analogy (ta de kat’ anologian); in number those whose matter is one, in species those whose formula is one, in genus those to which the same figure of predication applies, by analogy those which are related as a third thing to a forth.

While it looks as if Aristotle is here explicitly maintaining that matter is that which individuates, saying in effect that things are one in number when they are one in matter, there is some reason for caution. One source of confusion has been the tendency to confuse the relation of numerical sameness with that of unity or wholeness. In fact, Professor Łukasiewicz and Professor Anscombe, in interpreting Aristotle’s metaphysics, were thought to disagree over the “source of individuality,” the former taking the side of form, the latter that of matter, until Sir Karl Popper demonstrated that Łukasiewicz was treating a part-whole question, while Anscombe was taking up that of numerical sameness and difference.¹ Perhaps it is with this in mind that some scholars believe that Aristotle is not saying that matter is that in virtue of which things are numerically different, but that a continuous whole, or unitary object, is simply continuous with its matter.²

For example, when one says that the Northern Hemisphere and the Southern Hemisphere of a planet, make one object, or are one in number, one is discussing the way in which continuous parts make up one object or whole. And this part-whole relationship is different in kind from the relation to which we refer when, for example, we say that Hesperus and Phosphorus are one in number. For the terms “Hesperus” and “Phosphorus” name the same entity, namely, Venus, while “Northern” and “Southern” do not name the same entity, even though they may refer to different parts of the same entity.

In this way, it is possible that when Aristotle says “things are one in number whose matter is one,” he might be thought to mean that things like planets are one thing, rather than two, since their parts, say the Northern and Southern Hemispheres, are one, or continuous, in terms of their matter. He need not be saying, so runs the argument, that things such as Hesperus are numerically identical to Phospherus, that is Hesperus = Phospherus, in virtue of the fact that the relata have the same material nature. And if it is the former relation that Aristotle has in mind, we need not take the above text as evidence for the claim that Aristotle takes matter to be the principle of individuation.

There are, however, certain difficulties that face such an interpretation. For suppose we take Aristotle to be committed to the following claim:

(1) That, and only that, which is one is continuous in matter.

Aristotle will have to say that if something is one, it is continuous in terms of its matter, and if something is continuous in terms of its matter, it will be one. Two people shaking hands, however, might be thought to be continuous in matter (or we may suppose that their skin bonds together, is surgically conjoined, or, even, that the individuals are Siamese twins), but we are loath to say that they are one person. Furthermore, we may countenance things that are one but not continuous in their matter. A deck of cards is not continuous in terms of its matter, when it has been dealt in a game of Texas Hold’em, but surely the deck still exists.³

And the difficulties do not end here. As S. Marc Cohen has argued, there are two ways of interpreting (1):

(2) x is one individual if, and only if, x’s matter is continuous.

(3) x and y together make up a single individual, if, and only if, the matter of x is continuous with the matter of y.

If one could establish that (2) is the correct interpretation, then it would be somewhat more difficult to argue with the claim that the above text does not support the view that matter is the principle of individuation. And while it may seem plausible in isolation, it is difficult to square, or so it seems to me, with the actual passage. Aristotle is concerned in this chapter, as all will agree, with distinguishing oneness in number from oneness with respect to genus, form, and analogy. Thus, (2) and (3), where F is a formal, generic, analogical, or, let us say, arithmetical, predicate, have the form of (4) and (5) respectively:

(4) x is one in respect F.

(5) x is one with y in respect F.

However, (5), as Cohen points out, is a superior candidate to (4). For several Bekker lines earlier, 1016a24–7, Aristotle has just said the following:

Things are called one whose genus is one though distinguished by opposite differentiae; and these are called one because the genus which underlies the differentiae is one (e.g. horse, man, and dog are something one because all are animals).

Taking the reading represented by (4), then, requires us to take Aristotle’s point to be, for example, not that Equus caballus is one in genus with Canis familiaris, i.e. that both belong to the same genus, for that would involve a two-place predicate. Instead we would have to read Aristotle as simply asserting:

(6) Equus caballus is one in respect of genus.

But (6) is a strange locution. Why would someone state, of any given species, that it belongs to one genus? Why should one expect otherwise? Nobody would expect Equus caballus to belong to two genera. So it is better to understand the predicate in question to be of the two-place variety, as it is in (5), rather than the monadic predicate, as in (4). And if we take the subject of the paragraph to be treating two-place predicates rather than one-place predicates, the more consonant reading would be illustrated by the following:

(7) Tully is one with Cicero if, and only if, the matter of Cicero is identical with that of Tully.

Put another way, identity is expressed in terms of a two-place predicate: x is identical to y, where x might be the inventor of bifocals and y is Ben Franklin. Oneness, in contrast, is expressed in terms of a one-place predicate: x is one, or, the inventor of bifocals was one [individual]. But when Aristotle says that Socrates and Callias are one in form, as their account is one, he is making use of a two-place predicate. As a result, we should expect that in the passage in question, Aristotle is not simply talking about oneness. In particular, we may take him to be making use of a two-place predicate, in connection with the phrase “in number whose matter is one.” And if this is the case, we may understand him to be making the claim that substances of the same species are one, in the sense of being identical, whose matter is one.

One might counter that it is anachronistic to read Aristotle as being mindful of sentence-schemata, such as “x is one” or “x and y are one,” or that he is simply not in this passage concerned with such schemata.⁴ But the fact remains that reading Aristotle in these terms requires reading Aristotle as, at best, overlooking the distinction in question, and, at worst, as speaking equivocally. The traditional view, which reads Aristotle as upholding the view that matter is the principle of individuation, in contrast, need not visit this result on Aristotle.

The Zeta-eight passage

Another locus classicus for the traditional interpretation, to which we may turn our attention, is a passage that we have already encountered. This is the passage, we may call it the Zeta-eight passage, wherein Aristotle says explicitly that Socrates and Callias are distinguished in terms of their matter (1034a5–8):

And when we have the whole such and such a form in this flesh and in these bones, this is Callias or Socrates; and they are different in virtue of their matter (heteron dia tên hulên), for that is different, but the same in form, for their form is indivisible (atomon).

While this passage appears straightforwardly as evidence for the traditional view, those who would resist the received interpretation have sought to maintain that Aristotle is not, as it were, talking about what it is that makes Socrates and Callias different, but, rather, how one determines that Socrates and Callias are different. William Charlton, for example, says the following:

There is, I claim, nothing in this passage or its context to show that Aristotle is considering … [w]hat in the nature of specifically identical individuals makes them numerically distinct … rather than … how we tell one individual from another.⁵

Support for this claim is marshaled from Metaphysics X.9, we may call this the Iota-Nine Passage, where Aristotle seems to argue that qualitative differences do not make things different in species (1058b1–11):

And since one element is formula and one is matter, contrarieties which are in the formula make a difference in species, but those which are in the compound material thing do not make one. Therefore, whiteness in man, or blackness, does not make one, nor is there a difference in species between the white man and the black man, not even if each of them is denoted by one word. For man plays the part of matter, and matter does not make a difference; for it does not make individual men species of men, though the flesh and bones of which this man and that man consist are other. The compound thing is other, but not other in species, because in the formula there is contrariety. And this is the ultimate indivisible kind (atomon). Callias is formula together with matter; white man, then, is also, because Callias is a white man; man then is white only incidentally.

Charlton, if I understand correctly, believes that Aristotle, in this text, is saying that matter does not account for any metaphysical difference. The differences between a pale and a dark individual are incidental. That which underwrites the qualitative difference is a difference in material nature. As such, these differences are contingent, and unable to do the metaphysical work of individu...

Table of contents

• Cover Page
• Title Page
• Copyright Page
• Dedication Page
• Contents
• Introduction
• 1. Matters of Individuation
• 2. Resurrection and Entrapment
• 3. Aristotle on Composition and the Puzzle of Unity
• 4. Particularities and the Puzzle of Composition
• Conclusion
• Notes
• Bibliography
• Index