• §6. Category Theory
• The multivocity of "being" at the end of §5 is important for Aristotle's category theory.

Of things said without combination, each signifies either: (i) a substance (ousia); (ii) a quantity; (iii) a quality; (iv) a relative; (v) where; (vi) when; (vii) being in a position; (viii) having; (ix) acting upon; or (x) a being affected. (Cat. 1b25–27)

• what does the philosophical category theorist categorize?
• his examples make reasonably clear that he means to categorize the basic kinds of beings there may be.
  
• he starts the Categories speaking of things said "in combination" and things said "without combination": it looks as if he is talking about language:
• A thing said "in combination":
  
• Man runs.
• things said ‘without combination’:
• Man
• Runs
• But he is not speaking about language (at least so I think, pretty strongly)
  
• ‘Man runs’ is truth-evaluable, whereas neither ‘man’ nor ‘runs’ is.
  
• Things said without combination signify entities:
• sufficiently complex to be what makes the sentence ‘Man runs’ true, that is a man and is running
• below the level of truth-making, so, e.g., an entity man, taken by itself, and an action running, taken by itself, are not true or false by themselves
  
• If that is correct, the entities categorized by the categories are the sorts of basic beings that fall below the level of truth-makers, or facts.
  
• Such beings evidently contribute, so to speak, to the facticity of facts, just as, in their linguistic analogues, nouns and verbs, things said ‘without combination’, contribute to the truth-evaluability of simple assertions.
  
• If it is a fact that Socrates is pale, then the basic beings in view are Socrates and being pale.
  
• the first is a substance and the second is a quality, says Aristotle.
• these beings may be basic without being absolutely simple. After all, Socrates is made up of all manner of parts—arms and legs, organs and bones, molecules and atoms, and so on down. He is not absolutely simple.
  
• The theory of categories in total recognizes ten sorts of extra-linguistic basic beings:

• Category	Illustration
  Substance	man, horse
  Quality	white, grammatical
  Quantity	two-feet long
  Relative	double, slave
  Place	in the market
  Time	yesterday, tomorrow
  Position	lying, sitting
  Having	has shoes on
  Acting Upon	cutting, burning
  Being Affected	being cut, being burnt

• Surely meant to be exhaustive and irreducible:
  
• exhaustive: there are no further sorts of basic entities
  
• irreducible: none of these can be eliminated as being simply part of another
• BUT Aristotle offers no discussion of whether they really are exhaustive and irreducible
  
• Aristotle has slightly different lists of what look like categories here and there outside of the Categories.
  
• Kant praised A. for category theory, but criticized him for essentially brain-storming it instead of building and defending it systematically (Critique of Pure Reason, A81/B107). According to Kant, Aristotle's categories are groundless.
  
• Aristotle himself mainly tends to justify the theory of categories by putting it to work in his various philosophical investigations. It is not so much explicitly defended as functionally defended: it works...
  
• Example: time:
• Aristotle poses a simple question: does time exist?
  
• Yes, ‘time is the measure of motion with respect to the before and after’ (Phys. 219b1–2).
  
• time does exist, because it is an entity in the category of quantity
• like all items in any non-substance category, it exists in a dependent sort of way:
• just as if there were no lines there would be no length,
  
• so if there were no change there would be no time.
  
•  questions of existence are, at root, questions about category membership.
  
• Example: substance:
• If we ask whether qualities or quantities exist, Aristotle will answer in the affirmative, but then point out also that as dependent entities they do not exist in the independent manner of substances.
  
• Aristotle contends that all other things are either said-of primary substances, which are their subjects, or are in them as subjects.
• If there were no primary substances, it would be impossible for anything else to exist. (Cat. 2b5–6)
• the theory of categories spans his entire career and serves as a kind of scaffolding for much of his philosophical theorizing, ranging from metaphysics and philosophy of nature to psychology and value theory.
• but it is not entirely in harmony with everything he says: he may have developed his ideas over time. Categories is often considered early, with no great basis.
  

• §7. The Four Causal Account of Explanatory Adequacy
• Aristotle expects the explanations he seeks to meet certain criteria of adequacy. He takes care to state his criteria
  

One way in which cause is spoken of is that out of which a thing comes to be and which persists, e.g. the bronze of the statue, the silver of the bowl, and the genera of which the bronze and the silver are species.
In another way cause is spoken of as the form or the pattern, i.e. what is mentioned in the account (logos) belonging to the essence and its genera, e.g. the cause of an octave is a ratio of 2:1, or number more generally, as well as the parts mentioned in the account (logos).
Further, the primary source of the change and rest is spoken of as a cause, e.g. the man who deliberated is a cause, the father is the cause of the child, and generally the maker is the cause of what is made and what brings about change is a cause of what is changed.
Further, the end (telos) is spoken of as a cause. This is that for the sake of which (hou heneka) a thing is done, e.g. health is the cause of walking about. ‘Why is he walking about?’ We say: ‘To be healthy’— and, having said that, we think we have indicated the cause.
(Phys. 194b23–35)  

• example he proposes in Physics ii 3:
• A bronze statue:
• what is it?
• what is it made of?
• what brought it about?
• what is it for?
  
• in asking these questions we are seeking knowledge of the statue's four causes (aitia):
  
• formal
• material
• efficient
• final
• when we have identified these four causes, we have satisfied a reasonable demand for explanatory adequacy.
• In Physics ii 3, Aristotle makes twin claims about this four-causal schema: (i) that citing all four causes is necessary for adequacy in explanation; and (ii) that these four causes are sufficient for adequacy in explanation.
  
• Why necessary?
• not all phenomena admit of all four causes.
  
• coincidences lack final causes
• If a debtor is on his way to the market to buy milk and she runs into her creditor, who is on his way to the same market to buy bread, then she may agree to pay the money owed immediately. Although resulting in a wanted outcome, their meeting was not for the sake of settling the debt; nor indeed was their meeting for the sake of anything at all. It was a simple co-incidence. Hence, it lacks a final cause.
  
• mathematical abstractions lack material causes
  
• a triangle existing as an object of thought independent of any material realization will trivially lack a material cause.
• thus all four are not always necessary, but ordinarily, leaving one out leaves out a necessary part of an adequate explanation: so it's a sort of default to have all 4 rather than really being necessary.
• Why sufficient?
  
• The sufficiency claim is exceptionless
• But one might specify the material cause more or less proximately, by specifying the character of the matter more or less precisely.
  
• my arm is flesh and bone and sinew, but it is also carbon and hydrogen, but it is also electrons and protons: the flesh and bones and sinews are more proximately my arm.
  
• Not just any level of generality suffices.
• He means to insist that there is no fifth kind of cause: he challenges his readers to identify a kind of cause which qualifies as a sort distinct from the four mentioned. (Phys. 195a4–5).
• He thinks he can argue forcefully for the four causes as real explanatory factors, that is, as features which must be cited not merely because they make for satisfying explanations, but because they are genuinely operative causal factors, the omission of which renders any putative explanation objectively incomplete and so inadequate.
• some scholars have come to understand them more as becauses than as causes—that is, as explanations rather than as causes narrowly construed
• such judgments reflect an antecedent commitment to one or another view of causation and explanation—that causation relates events rather than propositions; that explanations are inquiry-relative; that causation is extensional and explanation intensional; that explanations must adhere to some manner of nomic-deductive model, whereas causes need not; or that causes must be prior in time to their effects, while explanations, especially intentional explanations, may appeal to states of affairs posterior in time to the actions they explain.
• Generally, Aristotle does not respect these sorts of commitments: his approach to aitia may be regarded as blurring the canons of causation and explanation. It is not clear how aware he is of that, whether he would consider it a problem, or how he would respond.
  

• §8. Hylomorphism
• matter (hulê) and form (eidos or morphê).
  
• Hylomorphism =df ordinary objects are composites of matter and form.
• "=df" means "is defined as"
  
• "ordinary objects" refers to such things as statues and houses, horses and humans.
  
• Hylomorphism holds that no such object is metaphysically simple, but rather comprises two distinct metaphysical elements, one formal and one material.
• formulated originally to handle various puzzles about change.
  
• A. insists all change involves at least two factors: something persisting and something gained or lost.
  
• Thus, when Socrates goes to the beach and comes away sun-tanned, something continues to exist, namely Socrates, even while something is lost, his pallor, and something else gained, his tan.
  
• This is a change in the category of quality, whence the common locution ‘qualitative change’.
  
• in whatever category a change occurs, something is lost and something gained within that category, even while something else, a substance, remains in existence, as the subject of that change.
  
• substances too can come into or go out of existence; and these are changes in the category of substance.
  
• in the case of the generation of a statue, the bronze persists, but it comes to acquire a new form, a substantial rather than accidental form.
  
• matter and form come to be paired by Aristotle with another fundamental distinction, that between potentiality and actuality.
  
• the bronze is potentially a statue, but it is an actual statue when and only when it is informed with the form of a statue.
  
• before being made into a statue, the bronze was potentially many things, but it was not potentially butter or a beach ball.
  
• form =df that which makes some matter which is potentially F actually F
• matter =df that which persists and which is, for some range of Fs, potentially F
• in Physics i 7 and 8, we have the following simple argument for matter and form:
  
• (1) a necessary condition of there being change is the existence of matter and form;
  
• (2) there is change;
  
• hence (3) there are matter and form.
  
• The second premise is a phainomenon accepted without further defense.
  
• The first premise is justified by the thought that since there is no generation ex nihilo, in every instance of change something persists while something else is gained or lost. In substantial generation or destruction, a substantial form is gained or lost; in mere accidental change, the form gained or lost is itself accidental. Since these two ways of changing exhaust the kinds of change there are, in every instance of change there are two factors present. These are matter and form.
• matter and form are mind-independent features of the world and must, therefore, be mentioned in any full explanation of its workings.

• §9. Aristotelian Teleology
• "teleology" is the idea that things have purposes, goals, ends that they are moving towards unless blocked
  
• The efficient cause requires a word or two first: Aristotle observes that nothing potential can bring itself into actuality without the agency of an actually operative efficient cause. Since what is potential is always in potentiality relative to some range of actualities, and nothing becomes actual of its own accord—no pile of bricks, for instance, spontaneously organizes itself into a house or a wall—an actually operative agent is required for every instance of change. This is the efficient cause. These sorts of considerations also incline Aristotle to speak of the priority of actuality over potentiality: potentialities are made actual by actualities, and indeed are always potentialities for some actuality or other. The operation of some actuality upon some potentiality is an instance of efficient causation.
• The final cause, the one that is invoked by "teleology," is quite controversial and difficult.
• easy cases: computers and can-openers are devices dedicated to the execution of certain tasks, and both their formal and material features will be explained by appeal to their functions.  we give them their functions. their functions are their purposes. they exist and are what they are only if they perform their function. All tools are functionally defined.
  
• more difficult: nature exhibits teleology without design. living organisms not only have parts which require teleological explanation— for instance, kidneys are for purifying the blood and teeth are for tearing and chewing food—but whole organisms, human beings and other animals, also have final causes.
• organisms have final causes, but were not designed. He thus denies that a necessary condition of x's having a final cause is x's being designed.
• most (not all) objections to Aristotle's final cause are stupid: any number of mind-numbing examples exist
  
• in the 19th century, German scholar Zeller was able to say with perfect accuracy that ‘The most important feature of the Aristotelian teleology is the fact that it is neither anthropocentric nor is it due to the actions of a creator existing outside the world or even of a mere arranger of the world, but is always thought of as immanent in nature’ (1883, §48).
• Aristotle offers two sorts of defenses of non-intentional teleology in nature, the first of which is replete with difficulty. He claims in Physics ii 8:

For these [viz. teeth and all other parts of natural beings] and all other natural things come about as they do either always or for the most part, whereas nothing which comes about due to chance or spontaneity comes about always or for the most part. … If, then, these are either the result of coincidence or for the sake of something, and they cannot be the result of coincidence or spontaneity, it follows that they must be for the sake of something. Moreover, even those making these sorts of claims [viz. that everything comes to be by necessity] will agree that such things are natural. Therefore, that for the sake of which is present among things which come to be and exist by nature. (Phys. 198b32–199a8)

• The argument here seems problematic.
• Aristotle seems to introduce as a phainomenon that nature exhibits regularity: humans tend to have teeth arranged in a predictable sort of way, with incisors in the front and molars in the back.
  
• He then seems to contend, as an exhaustive and exclusive disjunction, that things happen either by chance or for the sake of something
• Aristotle is himself aware of one sort of counterexample to this view and is indeed keen to point it out himself:
  
• bile is regularly and predictably yellow, its being yellow is neither due simply to chance nor for the sake of anything. Aristotle in fact mentions many such counterexamples (Part. An. 676b16–677b10, Gen. An. 778a29-b6).
  
• It seems to follow, then, short of ascribing a straight contradiction to him, either that he is not correctly represented as we have interpreted this argument or that he simply changed his mind about the grounds of teleology. Taking up the first alternative, one possibility is that Aristotle is not really trying to argue for teleology from the ground up in Physics ii 8, but is taking it as already established that there are teleological causes, and restricting himself to observing that many natural phenomena, namely those which occur always or for the most part, are good candidates for admitting of teleological explanation.
• this is a bit more detailed than is usual at this stage in our exploration of Aristotle, but it is useful, because it illustrates that Aristotle often needs our charity. We can catch him out in an apparent mistake, but if we think about it, and help him a little, he may have a very good point that is not a mistake at all...
  
• Perhaps he has a broader sort of motivation for teleology
• animals other than man make things using neither craft nor on the basis of inquiry nor by deliberation. This is in fact a source of puzzlement for those who wonder whether it is by reason or by some other faculty that these creatures work—spiders, ants and the like. Advancing bit by bit in this same direction it becomes apparent that even in plants features conducive to an end occur—leaves, for example, grow in order to provide shade for the fruit. If then it is both by nature and for an end that the swallow makes its nest and the spider its web, and plants grow leaves for the sake of the fruit and send their roots down rather than up for the sake of nourishment, it is plain that this kind of cause is operative in things which come to be and are by nature.
  
• Since nature is twofold, as matter and as form, the form is the end, and since all other things are for sake of the end, the form must be the cause in the sense of that for the sake of which. (Phys. 199a20–32)
• But perhaps all that talk of spiders and ants and plants doing things for some end is just imprecise and lax. We might yet demand that all such language be assiduously reduced to some non-teleological idiom when we are being scientifically strict and empirically serious
• we would first need to survey the explanatory costs and benefits of our attempting to do so. Aristotle considers and rejects some views hostile to teleology in Physics ii 8 and Generation and Corruption i.[22]

• §10. Substance
• Aristotle insists upon the primacy of primary substance in his Categories.
  
• star instances of primary substance are familiar living beings like Socrates or an individual horse (Cat. 2a11014).
  
• with the advent of hylomorphism, these primary substances are revealed to be metaphysical complexes
• now we have three potential candidates for primary substance: form, matter, and the compound of matter and form.
  
• which is the primary substance?
  
• The compound: we say that Socrates lives in Athens, not that his matter lives in Athens.
  
• The matter: it underlies the compound and in this way seems a more basic subject than the compound, at least in the sense that it can exist before and after it does.
  
• The form: the matter is nothing definite at all until enformed; so, perhaps form, as determining what the compound is, has the best claim on substantiality.
• Aristotle settles on form (Met. vii 17).
  
• He expects a substance to be, as he says, some particular thing (tode ti), but also to be something knowable, some essence or other.
  
• These criteria seem to pull in different directions:
• the first in favor of particular substances, as the primary substances of the Categories had been particulars
• the second in favor of universals as substances, because they alone are knowable.
  
• many scholars have concluded that Aristotle adopts a third way forward: form is both knowable and particular. This matter, however, remains very acutely disputed.
• Aristotle prefers form in virtue of its role in generation and diachronic persistence.
  
• When a statue is generated, or when a new animal comes into being, something persists, namely the matter, which comes to realize the substantial form in question.
  
• But the matter does not by itself provide the identity conditions for the new substance.
  
• the matter is merely potentially some F until such time as it is made actually F by the presence of an F form.
  
• the matter can be replenished, and is replenished in the case of all organisms, and so seems to be form-dependent for its own diachronic identity conditions.
  
• For these reasons, Aristotle thinks of the form as prior to the matter, and thus more fundamental.
  
• Further, in Metaphysics vii 17 Aristotle offers a suggestive argument to the effect that matter alone cannot be substance.
  
• Let the various bits of matter belonging to Socrates be labeled as a, b, c, …, n.
  
• Consistent with the non-existence of Socrates is the existence of a, b, c, …, n, since these elements exist when they are spread from here to Alpha Centauri,
  
• but if that happens, of course, Socrates no longer exists.
  
• Heading in the other direction, Socrates can exist without just these elements, since he may exist when some one of a, b, c, …, n is replaced or goes out of existence.
  
• So, in addition to his material elements, insists Aristotle, Socrates is also something else, something more (heteron ti; Met. 1041b19–20).
  
• This something more is form, which is ‘not an element…but a primary cause of a thing's being what it is’ (Met. 1041b28–30).
  
• The cause of a thing's being the actual thing it is, as we have seen, is form.
  
• Hence, concludes Aristotle, as the source of being and unity, form is substance.
• Feel free to entertain the following question: suppose your form is made up of formal parts A, B, C, ..., N: would you exist without some of them? Maybe: in that case, form as the cause of a thing's being a thing (in this case you being you) is vulnerable to the same objections as matter. So Aristotle needs to explain why parts of a form are not like material parts, or somehow meet this objection in another way.
  
• many questions remain. For example, is form best understood as universal or particular? (that is, is there a form of you that is peculiar to you and shared by no other human, or is your human form the same as every other human's form) However that issue is to be resolved, what is the relation of form to the compound and to matter? If form is substance, then what is the fate of these other two candidates? Are they also substances,  to a lesser degree? It seems odd to conclude that they are nothing at all, or that the compound in particular is nothing in actuality; yet it is difficult to contend that they might belong to some category other than substance.