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From the Greek τ εξτ τφυσικκά (what comes after the physical) and the Latin metaphysica (after or beyond the physical), ontology, first philosophy, theology, wisdom, the philosophical science having as object being as being (τò ν[symbol omitted]ν, whence "ontology"), or the study of the meaning, structure, and principles of whatever is and inasmuch as it is or exists. In its material object, or the number of things it studies, metaphysics is all-inclusive, extending to everything and every aspect of whatever is or can exist, whether of a material, sensible, physical nature or of a higher, nonmaterial nature (from which extension to the most perfect and divine it is called "first philosophy" or "theology"). Nevertheless, metaphysics retains its distinctive point of vision, or formal object, inasmuch as it is concerned with things as beings, that is, according to the relation that any thing or aspect of things has to existence, rather than to one of the particular aspects treated in the other sciences. The unity of this point of view, centered on what is most fundamental to all reality, enables metaphysics to investigate the way in which the many are interrelated to the one in some form of real unity. Further, since things are reflected in knowledge, it enables metaphysics to order and evaluate the various types of speculative and practical knowledge (whence the term "wisdom").

The etymological derivation of metaphysics has been explained generally, though, it seems, erroneously, according to the theory of J. G. Buhle (1763 to 1821): from the fact that Andronicus of Rhodes (1st century b.c.) placed the treatises of Aristotle on this subject after the Physics for lack of any proper position in his scheme of the first complete edition of Aristotle's works. However, the name has been traced with probability by H. Reimer to Eudemus of Rhodes (3d century b.c.), the first editor of Aristotle's works, for whom it reflected not only that the subject matter in some sense transcends the physical aspect of things, but also the corresponding Aristotelian concern for the order of learning as proceeding from the more immediately sensible to the transcendent.

This article considers metaphysics in two parts. The first is concerned with its history, and the second with its elaboration as a science.

History of Metaphysics

Metaphysical thought arises from the wonder generated by the tension between the characteristics of things experienced as multiple, individual, and contingent on the one hand and those of truth as one, universal, and necessary on the other. The history of metaphysics is constituted by man's progressing toward a more penetrating mode of vision (formal subject) and the correlative intrinsic and extrinsic principles that enable him to understand both the many as constituting one order of reality and the one truth in its multiple realizations.

Primitive Origins. That man's mind is naturally metaphysical is indicated by the vision of reality as a whole and the concern for explanation manifested in the ancient myths (see myth and mythology). In Greece these were summarized in the Theogony of Hesiod, which stated the parts of the universe in the anthropomorphic form of the gods, unifying them in a genetic series and identifying in Eros an active principle for their interrelation. To attain a more precise view of this unity, it was necessary to supersede the anthropomorphic and symbolic form of the myths in order to attain a more explicit identification of their intellectual content and its source. This step was accomplished in concrete and personal terms by the Hebrews and in abstract terms by the Hindus and others in the East and by the Greeks in the West.

The Jews, from their earliest history to the Babylonian Exile in the 6th century b.c., under the tutelage of divine providence came to see that persons and things, however many, were one in their common dependence on God or, more exactly, in their dependence on a common God. "I am the first and I am the last; there is no God but me" [Is 44.6]. This unity in things was paralleled in the intentional order, where individuals by their fundamental response of mind and heart related themselves and their world to God. The repetition of this relation in concrete terms for single types of things ("who made the heavens in wisdom, who spread out the earth upon the waters "Ps 135.56) manifests the need for a more abstract type of thought capable of identifying the proper extension and comprehension of the unifying relation to God.

The Oriental mind did carry metaphysical thought to the abstract and speculative level. hinduism in its scriptures, the upanishads, expressed a decisive appreciation of unity through the one impersonal substance, Brahman or Ātman, as the intimate reality of all things. However, fatally underestimating the world of experience as an illusion and source of suffering, it placed the road to wisdom in an ascetical and mystical science of withdrawal from activity and in a movement upward into natural contemplation of God as a prelude to reabsorption into Ātman. In the 6th century b.c., buddhism, having reduced all to empty phenomena in flux, held the supreme science to be one of deliverance from existence as such into the total indetermination called nirvĀna.

Greek Philosophy. The Greeks, in initiating their own speculative unification in the 6th century, b.c., possessed a firm appreciation of the reality of their world and a growing awareness of the value of intellectual clarity. Hence, their first steps were scientific in character, based on the evidence of the external senses and concluding in correlative terms that all was but particular states of water (Thales, c. 640 to 550) or other similar elements. Even here their concern opened beyond the merely physical to the metaphysical problem of overall unity, as is reflected in Anaximander's (c. 611 to 546) further reasoning to the "boundless" as beyond the diverse elements, unborn, all-encompassing, all-governing, and even divine [W. Jaeger, The Theology of the Early Greek Philosophers, tr. E. S. Robinson (Oxford 1947) 2436]. pythagoras (c. 580 to 500), in holding all to be numbers, attained a second level of evidence corresponding to the internal senses. Finally, parmenides arrived at the third, uniquely intellectual, and metaphysical appreciation of the real in its own proper term, being. "Being is; for To Be is possible, and Nothingness is not possible," [figure 6, K. Freeman, Ancilla to the Pre-Socratic Philosophers (Cambridge, Massachusetts 1957) 43]. Since being could differ only by nonbeing, or nothing, Parmenides denied anything other than the one absolutely perfect and unchanging sphere. This gave being the meaning of identity or what can be thought (figure 3, ibid. ; figure 2, 42), contrasting with the position of heraclitus (540 to 475) that all was becoming. This contrast reflected the attainment by Greek philosophy of the properly metaphysical: the real as suchthe explicit search for its internal and external principles and, in their terms, for the relation between the multiplicity manifested by experience and the unity appreciated by the mind. This search occupied the golden age of Greek philosophy.

plato (429 to 348) concluded from the fact of multiple beings to a principle of limitation or nonbeing as a "not-that-being" (Soph. 259A), and from the similarity among beings to something one or absolute in which the multiple participate as limited imitations. However, the combination of the Parmenidean meaning of being as intelligible identity with the Socratic method led to the transfer of reality from the multiple to that which the multiple imitate, the transcendent formal unities as Ideas to be contemplated and hierarchically ordered under the supreme Idea of the Good or the One (Republic 509). Man's highest calling and wisdom must then be to tend with all his powers, including the affective, to an ever clearer appreciation of the Ideas as the basis for guiding his actions (Symp. ).

aristotle (384 to 322), while retaining the goal of intellectual clarity and classically developing the division and structure of the sciences, initiated a more active understanding of form, based on a realist appreciation of the form of matter in changing things. This led him to forms separated from matter, which were not only objects of contemplation but themselves living, acting, knowing, and ultimately "the knowing on knowing" (νόησις νοήσεως νόησις Meta. 1074b 34). Related to this new level of reality was the distinct science of metaphysics, which in comparison to physics is both higher in dignity, because concerned with the unchanging, immaterial, and divine being, and broader in content, because concerned with being as being and hence all being (Meta. 1003a 201004a 1, 1025b 11026a 33). Aristotle, it seems, never perfectly conciliated the two understandings of metaphysics because his insight into being was not sufficient to allow for an understanding of the way in which the highest being could be the cause of being, as being in all beings. Despite the active understanding of form within the perspective of being as identity, form, and essence, the Parmenidean problem of the one and the many remained insoluble in these terms. This is seen from the limited attention given by the Greeks to the best manifestation of the simple affirmation of being, the person as a free and creative center in time and as capable of individual immortality. (see greek philosophy.)

Christianity. Christian thought presented the context for a penetrating insight into the act of being by underlining these very notions: in its distinguishing person from nature in the doctrine of the Trinity, and then in its heightening the appreciation of the created person's affirmation of self as gift in a response of love to the divine redemptive invitation to become sons, brothers, and heirs; and in its distinguishing creation from the Trinitarian processions, thus distinguishing form from the most formal effect of creation, the existence ("to be," or esse ) according to which a being is (the perfection of all perfections). The history of metaphysics in the Middle Ages consists in the major developments made possible by this more penetrating appreciation of being and evoked by the elaboration of the resultant theologies. These developments were made first on a more Platonic basis by St. augustine (354 to 430) and his school through St. bonaventure (1231 to 74), and then with an increasing addition of the Aristotelian systemization and realism by way of Arabian philosophy, culminating in the major syntheses of St. thomas aquinas (1224 to 1274), John duns scotus (c. 1274 to 1308), and others (see below).

Modern Era. Modern and contemporary metaphysics, finding the realistic metaphysics of being of the classical Christian philosophies of the Middle Ages already negated in the conceptualist philosophy of william of ockham (c. 1349) and his followers, proceeded to develop its metaphysics from the subject as manifested by the cogito of R. descartes (1596 to 1650). For the deleterious results, extending even to the negation of the possibility of metaphysics as a science, see metaphysics, validity of. Within this context, however, such classical rationalists as B. spinoza (1632 to 1677) and G. W. leibniz (1646 to 1727) contributed importantly to working out a logically deductive pattern of ideas; the schemata of the critical philosophy of I. Kant (1724 to 1804) and the dialectical sequences of G. W. F. hegel (1770 to 1831) further expressed reality's organic and developing character. Without realistic foundations, these philosophies inevitably progressed from positing that being is met in consciousness to idealism, holding that being is consciousness.

Contemporary metaphysics has sought to identify a place and a topic for metaphysical investigation that will be without presuppositions in order to allow the human mind most authentically to attain the real. In the transcendental phenomenology of E. husserl (1859 to 1938), philosophy is concerned with the knower and is directed toward grasping the world-constituting consciousness as such, rather than as one thing among many, because to grasp fully the possibilities of consciousness would be to grasp adequately being itself. For M. Heidegger (18891976), on the contrary, philosophy seeks the meaning of "to be" rather than of man, though the place of philosophical investigation is man in the world with others, the place in which "to be" has meaning for him. (see existential metaphysics and existentialism for a discussion of the existential emphasis in recent Thomistic thought and in contemporary forms of existentialism.) Together, the rationalistic and existentialistic developments of modern times have achieved a more reflective appreciation of man's grasp of being and of its personal dimension.

The Science of Metaphysics

The history of metaphysics manifests a universal striving of the human mind to clarify its appreciation of reality as a unified whole. To do this effectively, the mind must pass beyond the simple constatation of a unified reality to the discovery of its causes by means of science (scientia), the discursive process leading to the perfect knowledge of its subject by discovering its causes and attributes (Thomas Aquinas, In meta., proem.; In 1 anal. post. 2.3). As the attributes are related to the subject through the middle term, which is the real definition of the quiddity of the subject (In 2 anal. post. 1.9), the subject is not only the term concerning which knowledge is sought but also the source and norm of the scientific knowledge that concerns it. It was the diversity of meanings historically attributed to being (identity, substance, "to be") as the subject that lay at the root of the various forms of metaphysics noted above; and if a metaphysics is to be a study of reality itself as act or as a relation to existence, it can be so only if this be the nature of its proper subject.

Initiation of the Science. As there is nothing in the intellect that was not first in the senses, the realistic character of scientific knowledge immediately implies two levels of abstraction, of subjects, and hence of speculative sciences: physics abstracting from individual matter and proceeding on the evidence from the external senses to study things as expressed by qualities, and mathematics abstracting from common sensible matter and proceeding on the evidence of the internal senses to study things as quantified (see sciences, classifications of). Being, as a third level of formal subject prescinding from all matter, has been proposed on various bases: (1) a simple dissociation based on the mind's recognition that being and material are not equivalent, even though no special evidence for this be given; (2) a gradual process of removing the various specifications from being till there remains only a univocal "not nothing" of minimal significance; and (3) a separation of being as esse based outside the natural order on the common Judeo-Christian revelation of God as "I am who am" (Ex 3.14). Whatever be said about the distinctive value or problems of these approaches, the perfection of metaphysics as a distinct human science seems to require: first, that its subject, whose real definition is the middle term in the discursive process of metaphysics, be drawn from material things, the quiddity of which is the proper object of the human intellect (In Boeth. de Trin. 5.4); second, that the separation of a distinct meaning for being from material being be validated by the witness of actually existing nonmaterial beings (In 4 Meta. 5.593).

This fact of nonmaterial reality has been reflected constantly by man's commonsense appreciation of a power that transcends man; of the human person as a unique subject of justice, love, and freedom; and of his many social and artistic expressions. Although all these manifest a level of nonmaterial reality untouched by the sciences of the first two degrees of abstraction, the initiation of the science of metaphysics itself is better supported by the full strength of the scientific knowledge. Phenomenological investigations have usefully reflected on man as the crossroads where the flesh assumes the spirit and the spirit becomes incarnate; but the attainment of being as act is most amply founded on natural beings experienced as existing on as broad a base as can be provided by the following combination of all the nonmetaphysical sciences.

Aristotle's classical statement of the structure of the science of physics leads to the nonmaterial after identifying form and matter as changing being's intrinsic principles. However, this composition is shown in the Physics (books 7 and 8) to manifest a dependence for its ultimate explanation on something nonmaterial. Though, in physics, this can be described only in such negative and relative terms as "not material," "not changing," "not spatial," and "not temporal," physics does establish the existence of the nonmaterial as presupposed for whatever reality is had by physical substances and their accidents. In Aristotle's De anima and in his other psychological writings, the nonmaterial character of man's acts of intellection and volition are seen to manifest the nonmaterial character of his substantial form, or soul (see soul, human; spirit). Here, the extensive recent insights concerning human consciousness and freedom and the related significance of all dimensions of man and the universe give further indication of the reality and significance of the nonmaterial. Again, exemplary causality,, in relation to the speculative science of mathematics and its principles, allows the reality of the mathematical to manifest a higher and nonmaterial reality. Finally, in the practical order, the investigation of the end, or goal, required to open the full scope of man's free activity is seen as the contemplation of something transcending the material. Hence, as the human mind establishes the scientific processes by which it extends its knowledge with a controlled certainty and necessity to the various dimensions of reality, it becomes increasingly aware of the reality of the nonmaterial.

By this fact of immaterial reality, the mind is enabled to make the negative judgment of separation that the real is not necessarily material. It can also conclude that what makes the real to be real, the real precisely as real, is not materialthough, of course, many real beings are really material (In Boeth. de Trin. 5.3, 4, and ad 5). By this negative judgment the mind removes a restriction to its understanding of things. Hence, whereas previously, having attained all things through the senses, it spoke of reality precisely as sensible, it is now able to speak of these distinctively according to that by which they are real. The mind also knows that real is not simply a more general term for what had previously been stated more specifically. Because it knows that there are some things that exist but are not material, it knows that to speak of things precisely as real is to express them in a way that is more fundamental and penetrating than are any of their prior modes of attainment.

From the above, it can be seen that the common notion of being (being as being, being in general), which is the subject of the science of metaphysics, is expressed by "what is," for being affirms in act "what" is and of whatever kind, and does so by the "to be," which, as the actuality of all determinations of kind or nature, is the most formal element in being. Together the "what," or essence, and the "is," or "to be," or existence, express the notion of being (see being; essence and existence; potency and act).

From the foundation and mode of separation of being, it is also clear that the resulting notion is not a univocal least common denominator, whose differences have been progressively removed; rather, it actually includes the reality of all such differences precisely as real, even if only implicitly. At the same time, the notion of being is not equivocal (nominalism), lacking in any common significance in its application to the many different things. On the contrary, the notion of being is analogical; that is, it includes within itself the differences by which beings are really distinct one from anotherit is different simply in its application to distinct things while at the same time it has a certain similarity in its significance when applied to each of them (see analogy).

Elaboration of the Science. After it is seen that the subject of metaphysics is being, and that its mode is analogical, the first and necessary phase of the science of metaphysics is to identify the properties of its subject, thus unfolding its meaning. These properties could not be really distinct from being in its transcendence; rather, they express explicitly what already is implicit, but actual, in being itself (De ver. 1.1). They include unity, truth, goodness, and beauty. By unity being is identified as indivisible within itself, that is, as not shared with what it is not or with nonbeing and, by implication, as divided from all other beings (see unity). Being in its identity is able to be present in the intellect, and hence to be true (see all truth ). Being, as an intelligible identity, is also able to be related to the will, and hence to be good (see good). All of these are drawn together in the property of beauty, which is being inasmuch as it pleases when seen (see beauty). Parallel to these transcendental properties, and expressive of them in the form of judgments of being as possessing these properties, are the first principles of being (see first principles). To being as one, there correspond the principle of contradiction: being is not nonbeing; and the principle of identity: being is being, or being is itself. To being as true, there corresponds the principle of sufficient reason. Finally, to being as the transcendent good, there corresponds the principle of finality. Once the subject of metaphysics has been attained, these properties and principles can be discovered by an analytic process reflecting on the significance of what it means to be. In fact, Parmenides made notable accomplishments in this phase of metaphysics, even though he maintained that there could be but one being.

In order to go further into the science of metaphysics and to discover the intrinsic principles of its subject and the external relationship between beings, it is necessary to introduce the more synthetic phase of metaphysical method, wherein the mind returns to the experiential order and its evidence for a plurality of beings. This evidence, understood in terms of being as being and its property of unity, poses the problem of the one and many for the first time in direct metaphysical terms. This, indeed, includes two problems: first, how there can be more than one being or how being can be limited and, second, how these many beings, while differing one from another, can still be similar as beings.

The limitation of being opens to the mind the reality of a limiting principle that is not existence, but is inside the being, forming a unity with the existence to which it is related as potency to act. As allowing the mind to attain an insight into the internal structure of multiple and, hence, finite being, this reflection is of the greatest moment for the development of the science of metaphysics; in it, Aquinas achieved his synthesis of Christian platonism and aristotelianism. This discovery concerning internal structure is paralleled by another concerning extrinsic relations; this springs from the second problem, concerning the way in which the many can be similar as beings, and yet distinct from one another. This, together with the problem of the actuation of the potency, opens the path for the mind to Absolute Being, the cause of the subject of metaphysics. The essence of this Being is Its existence, a Subsistent Existence and pure act in which all multiple beings participate precisely as being, or according to their relation to existence. Thus is established a unity between all beings such that the absolute unity identified by Parmenides as characteristic of being is not destroyed but rather is opened out to a subordinate realm of multiple and participating beings (see participation).

In similar cycles the problem of the one and the many considered synthetically yields evidence of new unities. These are either unities of a specific kind among the multiple beings that lead to knowledge of the actpotency structure of form and matter within essence and further to the Divine Mind for the ultimate explanation of specific unities; or they are unities of many accidents as acts of the one substance, laying the foundation for a further union between beings by causality. Hence, the science of metaphysics gradually unfolds by a process of analysis and synthesis wherein it elaborates the internal principles and the external causes of its subject, being as being, and comes to understand all things in the light of these.

Characteristics. Such a metaphysics is supreme in universality, intellectuality, and certitude. (In Meta., proem.). The distinctive universality is had, first, according to comprehension, for the formal subject of the science is the most fundamental value of all, the relation to existence; second, according to extension, for, studying things as beings, the science is transcendent in its concerns, extending to every being and aspect of being; and finally, according to dignity, inasmuch as it carries the mind even to the divine in its search for the cause of its subject.

A second characteristic of metaphysics is its supreme intellectuality. Intellectuality is a mode according to which all is comprehended in one simple act and idea that attains the full truth of manifold beings and their principles. The human mind, proceeding abstractively, approaches this ideal imperfectly, but truly, to the degree that it is able to unify its knowledge of all things in one formal subject, through which it attains a uniquely simple, immediate, and comprehensive intellectual knowledge (In Boeth. de Trin. 6.1.3 ad 1). This special intellectuality is had by metaphysics inasmuch as its formal subject is being, the common object of the intellect and the source from which its principles are derived immediately and its conclusions most directly. Hence, if difficult of attainment, metaphysics has a most profound proportion to the human intellect, with its actual and possible openness to being.

The third characteristic of metaphysics as a science follows from the above. This is its special objective certitude, which derives from its subject and from its reasoning processes, as founded and verified in the first and most evident of all principles, the principle of contradiction.

Fourth, as the science that is most perfectly universal, intellectual, and certain, metaphysics takes on the character of natural wisdom. For if the wise man, as Aristotle describes him, must have universal and difficult knowledge, greater than ordinary certitude, and a capacity to identify causes, to seek knowledge for its own sake, and to be able to rule others, then metaphysics fulfills this necessity. It is the most universal science, extending even to what most transcends the human mind; yet it has the greatest certitude and commitment because concerned with being itself; and finally, because it knows the principles of all being, it is able to rule and direct the sciences that are concerned with particular types of beings. Metaphysics, therefore, stands at the culmination of man's knowledge; it derives from a negative judgment based on evidence from all the sciences, and, as a potential whole, it is present in the exercise of all other intellectual virtues, wherein it is but partially expressed. Since it uses other sciences to enlarge its knowledge, its ordering function in their regard is part of the work of wisdom itself.

Thus metaphysics takes on a supreme human value."The ultimate perfection which the soul can attain, therefore, is, according to the philosophers, to have delineated in it the entire order and causes of the universe. This they hold to be the ultimate end of man. We, however, hold that it consists in the vision of God" (De ver. 2.2).

See Also: wisdom; theology, natural;christian philosophy; philosophy.

Bibliography: c. fabro, La nozione metafisica di partecipazione secondo S. Tommaso d'Aquino (2d ed. Turin 1950); Participation et causalité selon S. Thomas d'Aquin (Louvain 1961). j. definance, Être et agir dans la philosophie de saint Thomas (Paris 1945). É. h. gilson, Being and Some Philosophers (2d ed. Toronto 1952). t. c. o'brien, Metaphysics and the Existence of God (Washington 1960). l. j. eslick, "What Is the Starting Point of Metaphysics?" The Modern Schoolman 34 (1957) 24763. l. b. geiger, "Abstraction et séparation d'après S. Thomas," Revue des sciences philosophiques et théologiques 31 (1947) 340. a. mansion, "Philosophie première, philosophie seconde et métaphysique chez Aristotle," Revue philosophique de Louvain 56 (1958) 165221. r.w. schmidt, "L'emploi de la séparation en métaphysique," ibid., 58 (1960) 37393. j. d. robert, "La métaphysique, science distincte de toute autre discipline philosophique, selon saint Thomas d'Aquin," Divus Thomas 3d series 50 (1947) 20622. v. e. smith, "The Prime Mover: Physical and Metaphysical Considerations," American Catholic Philosophical Association. Proceedings of the Annual Meeting 28 (1954) 7894. h. heiner, "Die Entstetehung und ursprungliche Bedeutung des Namens Metaphysik," Zeitschrift für philosophische Forschung 8 (1954) 21037. t. andoŌ, Metaphysics: A Critical Survey of Its Meaning (The Hague 1963). g. gusdorf, Mythe et métaphysique (Paris 1953).

[g. f. mclean]

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