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Categories of Being


The categories of being are defined variously as the most general predicates expressive of real being or as pure conceptions of the understanding. The most important and influential doctrines on the categories are those of aristotle and kant. Since Aristotle's elaboration of a doctrine of categories is prior to Kant's and may well have been the first (see Plato, Soph. 254B, for a possible adumbration), it is granted priority of exposition here.

The Greek term κατγορίαι, meaning predicates, links the doctrine of categories with the proposition. This simple fact has been the cause of a number of different views on the origin and nature of the doctrine of categories in Aristotle. Some have maintained that the doctrine arose from a consideration of grammar; others that it is a logical doctrine that came to have ontological import; others that, originally an ontological doctrine, it came to be expressed in logical terminology. Since there was no developed grammar in the relevant sense for Aristotle to rely on and since the doctrine of categories makes distinctions where grammar would not and does not honor possible grammatical distinctions, the first view is implausible. The other views involve a problem that, as applied to Aristotle, is often anachronistic. For when it is asked whether the doctrine of categories is logical or metaphysical, it is not always clear whether the question turns on the meaning these adjectives might have had for Aristotle or on the meaning they have today. Yet, even when restricted to the Aristotelian perspective, one cannot always grasp the precise import of a given statement about the categories. If the categories are predicates and genera, it is not the case that every predicate falls within a category. Indeed, Aristotle broaches the problems of metaphysics by way of the categories, thereby indicating that the categories are not a list of just any uses of being, but are rather the highest genera predicable of real being as opposed to accidental being. Therefore, if the categories, since they are genera, are logical, they are logical relations that attach to real being. In short, they are not classifications derived from language simply, but classifications found in language expressive of real being.

Aristotle's treatise on categories. Although its authenticity has been questioned, most scholars now accept the Categories as the work of Aristotle. This treatise prefaces the actual listing of the supreme genera with a number of distinctions that indicate what the author intends to do. First it notes that some verbal expressions are complex while others are incomplex. A complex verbal expression is one that admits of truth or falsity; for example, "The man runs." Incomplex expressions are neither true nor false and can be components of complex expressions. Examples of incomplex expressions are "man" and "runs." The categories themselves are incomplex expressions.

Aristotle then distinguishes being predicable of a subject and being present in a subject. To be present in a subject means to pertain to the subject accidentally and not essentially; thus what is present in a subject in this sense is not part of the subject's quiddity. The author adds that what is present in a subject is incapable of existence apart from a subject. What is predicable of a subject, on the other hand, means whatever can be said of a subject whether essentially or accidentally. Predicability involves universality and on this assumption, Aristotle divides things themselves as follows: (1) Some things are predicable of a subject but are never present in a subject; the author has in mind universal expressions of what a thing is, such as "man". (2) Some things are present in a subject but are never predicable of a subject; such are singular accidents, for example, a particular whiteness.(3) Some things are both predicable of a subject and present in a subject; these are accidents considered universally, for example, whiteness. (4) Finally, some things are neither present in a subject nor predicable of a subject; for example, the individual man or the individual horse.

Substances are precisely things of this fourth kind. Aristotle calls such singular entities first substances; second substances are all predicates that can be affirmed essentially of first substances, that is, things falling in the first class. Examples of second substance, accordingly, are: man, horse, animal, living organism and finally, substance itself.

If man can be predicated of Socrates and animal can be predicated of man, then animal can be predicated of Socrates. This observation indicates that a hierarchy of predicates can be found that will end ultimately with such terms as substance.

Aristotle then lists his categories: "Incomplex expressions signify either substance, quantity, quality, relation, place, time, situation, condition, action or passion" (Cat. 1b, 2527). Aristotle offers the following examples of things of which these are predicated as supreme genera: of substance, man or horse; of quantity, two inches long; of quality, white and grammatical; of relation, double, half and greater; of place, in the market, in school; of time, last year and yesterday; of situation, lying and sitting; of condition, shod and armed; of action, to lance, to cauterize; of passion, to be lanced, to be cauterized. Such expressions are neither true nor false, although true or false expressions are composed from them.

Categories and real being. Aristotle's intention in enumerating these ten highest predicates or supreme genera is not made explicit in the Categories, as it is elsewhere. That he was not merely classifying all possible predicates is evident enough from the Metaphysics (1017a, 71017b, 9). Acutely aware of the variety of uses and meanings of "is" and "being," Aristotle emphasizes that not every use of these terms is relevant to the science of being as being. Some uses do not purport to assert that what is said "to be" exists independently of human knowledge. Yet even when interest is confined to real being, "being" and "is" do not have a unique sense. "On the other hand, the varieties of essential being are indicated by the categories; for in as many ways as there are categories, may things be said to be. Since predication asserts sometimes what a thing is, sometimes of what sort, sometimes how much, sometimes in what relation, sometimes in what process of doing or undergoing, sometimes where, sometimes when, it follows that these are all the ways of being" (1017a, 2227; tr. Hope).

In an effort to understand the things that are, man arrives at knowledge that expresses itself in such propositions as "Socrates is man," "Socrates is seated," "Socrates is five feet tall." Predicates attributed to such entities as Socrates are not all of a piece, however, though some (for example, "man," "animal" and "living thing") are related as more and less general. To say of Socrates that he is seated is not an expression of what Socrates is essentially, but of something "present in him." Since for a thing to be is for it to be something or other and what it is said to be relates to it, either essentially or accidentally, the categories are the logical arrangement of predicates expressive of modes of real being.

Logic vs. ontology. Is Aristotle's teaching on the categories a logical or metaphysical doctrine? To be a substance or an accident is a mode of real being; the names of the supreme genera, like the names of subordinate genera and of the ultimate species, are not logical terms. Moreover, Aristotle speaks of the categories of being. On the other hand, to be a predicate is no more an ontological characteristic than to be a genus, species or difference and yet these terms figure prominently in the elaboration of the doctrine (see predicables).

Such considerations have led a significant number of scholars to say of the doctrine of categories that it lies in the shadowy region between logic and ontology. Perhaps it is more accurate to say that what is categorized is real being, but that to be categorized, to be a genus or species, is to take on a logical relation. If it is generally true that logical relations attach to real things because of our way of knowing them, the apparently anomalous character of the categories also furnishes a general view of the nature of the logical. There is nothing merely logical about being a substance, but to say of substance that it is a supreme genus is to relate the content of one concept to the meanings of a number of predicates subordinate to it, and like it, expressive of the natures of things like Socrates and Alcibiades. To say of substance that it is a category, then, is like saying of horse that it is a species; in both cases one is asserting of something real a kind of predicability that is consequent upon man's abstractive manner of knowing real things (see abstraction).

The reluctance to call the doctrine of categories logical is based on the recognition that substance, quantity, quality, etc., signify modes of real being; the reluctance to call the doctrine ontological is based on the recognition that the ascending series of predicates, man-animal-living substance, does not answer to any real division in the thing of which all these terms are predicated. Moreover, it would be fallacious to argue as follows: Substance is a supreme genus; man is a substance; therefore, man is a supreme genus. For real being to fall into the schema of the categories, it must be universal, but universality and predicability are not ontological characteristics. Therefore the correct conclusion is this: only real being falls under the categories; but, in order to be in a category, real being must be considered as the subject of such logical relations as predicability, genus and so forth.

Kantian categories. Kant arrives at his categories, which are principles of pure or a priori synthesis on the part of the understanding, by a consideration of classes of judgment (Kritik der reinen Vernunft ). These classes are more reminiscent of Aristotle's On Interpretation than of his Categories, for they involve the comparison of propositions with respect to their quantity, quality and modality, together with the notion of simple and complex propositions. Kant suggests that, if one abstracts from the content of judgments and concentrates on their form alone, he finds that the function of thought in a judgment can be brought under four headings: quantity, quality, relation and modality. Each heading comprises three "moments." With respect to quantity, judgments are universal, particular or singular; with respect to quality, they are affirmative, negative or infinite; with respect to relation, they are categorical, hypothetical or disjunctive; with respect to modality, they are problematical, assertorical or apodictical. Kant gives at this point a hint as to why he has called these trichotomies moments. Speaking of modalities of judgment, Kant says that problematical judgments are those in which an affirmation is accepted as merely possible; in assertorical judgments the affirmation is regarded as true; in the apodictical it is regarded as necessary. In a note he suggests that it is as if thought were in the first instance a function of understanding, in the second of judgment and in the third of reasoning.

Kant connects what he chooses to call categories with these divisions of the form of judgments: by a category he means a pure conception of the understanding applicable a priori to objects of intuition. Since the table of judgments exhausts the function of the understanding, one should be able to arrive at an exhaustive enumeration of categories. The categories of quantity are unity, plurality, totality; those of quality are reality, negation and limitation; the categories of relation are substance and accident, cause and effect and reciprocity between agent and patient; those of modality the pairs: possibilityimpossibility, existence-nonexistence, necessity-contingency. The function of the categories is to render the manifold of sensuous intuition conceivable; they are, so to speak, the a priori patterns of understanding that constitute the objectivity of objects. Kant compares his own results with Aristotle's and observes that the Greek philosopher, not having a guiding principle, hit upon his categories in a haphazard and adventitious manner.

Criticism of the categories. Kant's doctrine of categories is neither the same sort as Aristotle's, as he misleadingly suggests, nor a relevant criticism of the earlier doctrine. The term category functions so differently in these authors that no direct comparison of the two lists of categories is illuminating. One must rather go to the most general presuppositions of Aristotelian and Kantian philosophy. Depending on which basic option one prefers, one of these doctrines will be regarded as hopelessly wrongheaded; in more sanguine moments, one will doubtless find some remote glimmer of plausibility in the other view, though not think of it as a doctrine of categories.

Difficulties of much the same kind arise when one turns to contemporary discussions of categories that are influenced by the theory of types (see antinomy). Such discussions often suggest that Aristotle intended to formulate a general theory of types of predicate, and find, of course, that the Aristotelian categories are woefully inadequate. Here, too, the initial impression that wholly opposed views are being juxtaposed soon gives way to the thought that the views may after all be complementary. Such an irenic moment is achieved, however, at the expense of any genuinely common meaning of the term category, since agreements are not reached under the aegis of what either side would be willing to call categories.

The main complaint of J. S. mill against the Aristotelian categories was that they left out of account such realities as man's feelings. One is tempted to see as akin to Mill's more recent suggestions that, since the categories are classifications of things and man is not a thing, "existentials," or categories of human being, must be devised.

The fate of the Aristotelian doctrine of categories depends on one's ability to resist the anachronistic impulse to see what adumbrations of familiar procedures can be discovered in Aristotle and to regain the more basic kind of thinking underlying science and logic that permeates Aristotelian philosophy. From a variety of quarters, notably from phenomenology, philosophers are being urged to recognize the continuing and fundamental validity of a knowledge that requires taking the knower into account. Perhaps it is only by heeding these suggestions that one can grasp the nature of the Aristotelian categories.

See Also: substance; accident; quantity; quality; relation; place; situation (situs); action and passion; time.

Bibliography: l. m. de rijk, The Place of Categories of Being in Aristotle's Philosophy (Assen, Netherlands 1952). m. scheu, The Categories of Being in Aristotle and St. Thomas (Catholic University of America, Philos. Stud. 88; Washington 1944). r. j. blackwell, "The Methodological Function of Categories in Aristotle," The New Scholasticism, 31 (1957) 526537. j. a. oesterle, Logic, the Art of Defining and Reasoning (2d ed., Englewood Cliffs, N.J.1963). l. de raeymaeker, The Philosophy of Being, tr., e. h. ziegelmeyer (St. Louis 1954). r. e. mccall, The Reality of Substance (Catholic University of America, Philos. Stud. 168; Washington 1956). g. ryle, "Categories," Logic and Language, ed., a. g. n. flew (2d series; New York 1953) 6581. e. freeman, The Categories of Charles Peirce (Chicago 1934).

[r. m. mcinerny]

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