A Mini-Course in The Philosophy of Aristotle

These mini-courses study the growth of philosophy after its emergence in the early Greek Schools, and traces the development of philosophic thought from Socrates to its relatively full expression in the magnificent synthesis of Aristotle in the 4th century B.C. Also discussed is the retrogression of philosophy after Aristotle. Part I discusses the philosophy of Socrates and Plato. Part II discusses the philosophy of Aristotle. Part III discusses the course of philosophy after Aristotle.

Part II of The Development of Philosophy is divided into five Sections:
•Section 1: Aristotle
•Section 2: Logic
•Section 3: Physics
•Section 4: Metaphysics
•Section 5: Ethics

Section 1: Aristotle

Aristotle was born in 384 B.C. at Stagira (and hence he is called “The Stagirite”) in ancient Chalcis. His was perhaps the finest mind, in natural gifts, that the world has ever known. For twenty years he was a pupil of Plato, carrying on meanwhile his private researches in philosophy and in physical science. He had an interest in biological study, and it is likely that he did some dissecting under the eye of his father, Nichomachus, who was court-physician to the king of Macedon. Aristotle spent some time in travel, and afterwards he was tutor to the young Alexander whom the world was to know as “the Great.” Then he set up as a teacher in Athens. His pupils about him, he lectured as they all walked slowly up and down the shaded walks of the Lyceum of Apollo. And thus his school came to be known as “the peripatetics,” a name derived from the Greek perpatein “to walk about.” After a dozen years of teaching, Aristotle incurred the displeasure of the politicians, for he had acquired too much influence with the young men of Athens to be a safe person to have about. He quietly slipped away, and died a natural death in Euboea in 322. B.C. when he was sixty-two years of age.

We have some of Aristotle’s writings, although certain critics think these are but notes taken by his more gifted pupils. No such masterful style appears in these works as graces the writings of Plato. If Aristotle really wrote them, he did not take the time to edit them and set them in finished order. Yet, for all that, these writings are among the most precious pages that the world possesses.

We group the writings of Aristotle under four heads: Logic (the Organon, or, as he called it, Analytic); Physics; Metaphysics; Ethics.

Section 2: Logic

Logic is the science of correctness in the human knowing-process. For thinking must be correct if it is to lead one securely to knowledge that is true and certain. Today we distinguish in Logic a twofold science: one, the science of correct thinking, of legitimate procedure in reasoning; we call this Formal Logic or Dialectics; the other, the science of truth and certitude as achievable by thinking, that is, by reasoning; we call this Major Logic or Criteriology. Aristotle, with perfect scientific acumen, assigned the study of truth and certitude to metaphysics.

Aristotle invented the science of Formal Logic or Analytic, and he developed it into a rounded and relatively perfect thing. Of few men and of few achievements may such a statement be made.

The mind has three major operations: it directly knows things (that is, it grasps essences in an abstract manner); it compares its findings and judges their agreements and disagreements (that is, it pronounces upon what it knows); finally, it works out further judgments by reasoning upon judgments already formed. The first of these operations is called apprehending; the second, judging; the third, reasoning. The purpose of Formal Logic or Dialectics (or of Analytic) is to discern the mode of procedure which the mind must follow to insure a reliable result; it is to discern the “laws of thinking”; it is to know hoe and wherein the three operations, and especially the last (i.e. reasoning), are legitimate and justified.

Aristotle analyzed the mental processes with enlightened accuracy. Discerning the fact that the mind, by its native power, rises from the findings of the senses to reality that lies beyond sense-grasp, and abstracts from the individual character of sense-objects to know things in universal, he goes on to set forth and prove the existence of three grades of mental abstraction, the physical, the mathematical, the metaphysical. These three grades or degrees of mental abstraction are important in themselves and also as the proper bases of the classification of the sciences which deal with extramental reality.

Apprehending supplies the mind with elemental knowledge, that is, ideas or concepts which are the mental representations of essences. Then the mind goes to its proper work of judging, pronouncing, recognizing truths, connecting subject-idea and predicate-idea. Judging is the fundamental thought-process. The operation called reasoning is but a series of judgings, connected, related, leading to a final of judging and pronouncing some agreement, — that is, bringing together some subject and some predicate, — or disagreement, — that is, denying some predicate of some subject. In a word, reasoning is a roundabout way of arriving at a judgment which is not immediate manifest to the mind. Judging is the basic, the essential process of thinking.

Now, in judging, the mind pronounces on the agreement or disagreement of ideas or concepts; the mind associates or dissevers a predicate-idea and a subject-idea; the mind affirms or denies a predicate of a subject. Thus judging is predicating. Aristotle discerns five ways in which predicating takes place; every judgment is necessarily made according to one of these five ways. The Five Modes of Predicating are called the predicables (in Greek, categoremata). These are: Genus, Species, Difference, Property or Attribute, and Accident. To explain and illustrate:

(a) Genus — When the mind predicates one idea of another (applies predicate-idea to subject-idea) in such wise that the predicate expresses that part of the essence of the subject which the subject has in common with other things from which it is none the less essentially distinguished, the predicate-idea is called the genus of the subject-idea, and the judging or predicating is called generic. Thus, in the judgment, “Man is animal,” the predicate-idea “animal” expresses part of the essence “man,” but not all of that essence for man is more than animal; the predicate-idea expresses that part of the essence “man” which man has in common with other things, namely, non-rational animal beings.

(b) Species — When the mind predicates one idea of another (i.e., predicate of subject) in such wise that the predicate expresses or defines the entire essence of the subject perfectly and exclusively, the predicate-idea is the species of the subject-idea, and the judging or predicating is called specific. Thus, in the judgment, “Man is rational animal,” the predicate-idea expresses completely, perfectly, and exclusively the essence of the subject-idea. This predicate applies to no other subject. The predicate is the species of the subject.

(c) Difference — When the mind applies predicate-idea to subject-idea in such wise that the predicate expresses that part of the essence of the subject which marks the subject off from other things with which it has a common genus, the predicate is called the difference (or the ultimate difference or the specific difference) of the subject. Thus, in the judgment “Man is rational,” the predicate-idea expresses what distinguishes the subject-idea from another idea which has with it a common genus, that is, from non-rational animal. The judging or predicating here is called differential.

(d) Property or Attribute — When the mind applies predicate-idea to subject-idea in such wise that the predicate expresses what belongs to the subject by natural necessity but is no constituent element or part of its essence, the predicate is called the property or the attribute of the subject, and the judging or predicating is called proper. Thus, in the judgment, “Man is a-being-that-can-laugh” the predicate-idea expresses what belongs by nature to the subject although it is no part of the essence of the subject.

(e) Accident — When the mind applies predicate-idea to subject-idea in such wise that the predicate expresses what may belong to the subject, although this is no part of the essence of the subject, nor does it follow naturally upon the nature of the subject by any necessity, the predicate is called the accident of the subject, and the judging or predicating is called accidental. Thus, in the judgment, “Man is a-being-that-can-read” the predicate-idea expresses what may happen to be true of the subject, but is not necessarily so.

Notice carefully that the predicables are modes of judging in the mind. They are in no wise classifications of things. Nor are they, strictly speaking, classifications of ideas. They are modes or ways in which one idea may apply to, or be predicated of, another.

Now, the things or realities which are represented in the mind by ideas, are classified, according to their intelligibility or reference to the mind, under ten heads called the predicamentals or the categories (in Greek, categoriai). Aristotle resolved all knowable things into these ten supreme genera or master classes. There are, indeed, certain points of fact that the mind can consider which do not directly fall under any of the categories or predicamentals; these things are called pre-predicamentals and post-predicamentals. Yet, indirectly, or analogously, everything to which the mind of man can turn its attention is ascribable to one of the ten categories. Literally, they are classifications of understandable finite being; yet, by analogy, even the infinite Being is viewed as pertaining to the first of the categories or predicamentals. To determine these classes, and so to construct a workable plan for the philosopher whose task is the deep investigation of reality, Aristotle reasoned out a list of the basic questions that the mind must ask in its effort to know all that can be known of anything. These questions are ten and only ten. Two thousand years and more of incessant testing have proved beyond quibble that none of the questions is superfluous and that no additional questions need be asked, or, indeed, can be asked. The answers to the ten fundamental questions are the categories or the predicamentals. Notice carefully that the predicamentals are not merely a list of things, but a list of the supreme classes of things as understandable. Questions and categories are these:





1. What (is the thing itself)?  Substance or one of Nine Accidents

2. How much?  Accident of Quantity

3. What sort?   Accident of Quality

4. In what comparison or reference?   Accident of Relation

5. What doing?   Accident of Action

6. What undergoing?   Accident of Passion

7. Where?   Accident of Place

8. When?   Accident of Time

9. In what position or attitude?  Accident of Posture or Position

10. With what externals or vesture?  Accident of Habit

As we have seen, judging is the basic thought-process. But judgment is very often balked by insufficient clarity of knowledge (or, more precisely, of ideas or concepts), and it becomes necessary to reason out the judgment. Two ideas may not, in themselves, be so clear in the mind that it can say that they are in agreement or disagreement. In this case, the mind uses a third idea which is known in its reference to the original two, and through the medium of this common third idea the relation (of agreement or disagreement) of the original two ideas may be recognized. Such is the process of reasoning. And its expression (in the mind, or outwardly in speech or writing or other sign) takes the shape of what is called a syllogism.

A judgment is expressed (mentally or verbally) in a proposition. A syllogism consists of three propositions or expressed judgments. The first two (which express the relations of two ideas to a common third) are called premisses. The last (which expresses the relation of the original two ideas, known by their relations to the common third idea) is called the conclusion. Here we have a syllogism:

First or major premiss: Every tree is a plant

Second or minor premiss: The oak is a tree

Conclusion or consequent: Therefore, the oak is a plant

Reasoning is the syllogism and the syllogism is reasoning. Those shallow critics who scoff at the syllogism, are forced to express their scoffing in syllogisms. For this is the way the mind works, and there can be no quarrel with it. This is its nature. This is its fixed mode of action. There is no other way to think things out. A man might as well quarrel with the structure and action of his feet, and expect them to hear or speak, as to find fault with the “mental triangulation,” that is, the syllogism, by which the mind works out truths that are not immediately evident.

Reasoning is either deductive or inductive. When (as in the example just given) the reasoning process or syllogism proceeds from a general or universal truth to a particular or individual application or expression of it, the process is deductive reasoning or simply deduction. The principle (i.e., the basic guiding truth) of deduction is this: Whatever is true of all members of a class is true of each member; whatever is to be denied of all is to be denied of each. When the reasoning process or syllogism proceeds from individual instances to general or universal conclusion, the process is inductive reasoning or simply induction. The principle of induction is this: Whatever is true of each member of a class is true of all members; whatever is to be denied of each is to be denied of all. Deduction and induction are complementary, not opposed, methods of reasoning. The nature of the investigation and the state of the mind’s information to begin with, indicate which method is to be used.

Since induction is the only instrument available to the laboratory scientist, it has come to be called “the scientific method.” Yet the whole purpose and drive of this method is to arrive at general or universal truths which will enable the investigator to deduce conclusions. If induction is used to determine the nature of water, and it is discovered that water is H20, then deduction is thereafter used to determine that if the stuff under consideration is water it is necessarily H20.

Students whose knowledge of the history of philosophy is inadequate have hit upon Roger Bacon, a philosopher of the 13th century, as the inaugurator of the inductive method, especially when it is smugly called “the scientific method.” Yet Aristotle made notable use of the inductive method.

Section 3: Physics

The term “physics” means, as a department of philosophy, the philosophical science of mobile or changeable being. It is not to be confused with the experimental science of physics which the name usually indicates in our day. Physics here is a department of philosophy; it seeks ultimate causes and reasons. It is the philosophy of the universe of bodily things around us. It is Natural Philosophy.

Aristotle accepts the reality of change or “becoming.” Thus he opposes the fantastic and unreal theory of the Eleatics. Now, the most manifest sort of change or movement is found in the bodily world around us, of which we are a part. Thus Aristotle’s physics deals primarily with the cosmological question, the question of the root-constitution, and the activities, of bodily things. Since man is bodily, despite the fact that his most important element is spiritual, he falls under the consideration of Aristotelian physics; thus we have also here a discussion of the psychological question, the question of life and living bodies.

A body, lifeless or living, is bodily. All bodies are at one in this point, no matter how great their essential differences in other respects. And bodies do differ essentially. There is an essential difference between the body called a boy and the body called a dog; between the body called a tree and the body called a rock. As bodies they are at one; each is as truly body as the others. But they are not the same essential kind of body. Aristotle teaches that the identity of all bodies in bodiliness is owing to the fact that all bodies have a substratum of primal matter. And each body is constituted in its essential kind, each is made an-existing-boy-of-this-specific-sort, by its substantial form or substantifying determinateness, — for “form” is not to be taken lightly as a word meaning mere shape or outline or something accidental; it is here substantial form. An existing body is ultimately (i.e., philosophically) explained as the substantial union of primal matter with substantial form. This doctrine came to be known as hylemorphism (sometimes spelled hylomorphism), a term which derives from the Greek hyle “matter,” and morphe “form.”

Primal matter (or, as it is more commonly called, prime matter) is the wholly passive substantial substrate of all existing bodies. It has no proper existence of its own. It exists only in existing bodies, that is, in bodies in-formed by substantial form. Prime matter is a substance, but not a complete substance; it requires the co-substance called substantial form to give it existence in existing bodies. Prime matter is the most imperfect of things; it has no determinateness at all (for determinateness is a “form,” substantial or accidental); it is “form-less” in itself. It might be called the substantial capacity for bodily existence, but it is not an independently existing capacity. A body comes into actuality, into real existence, when substantial form in-forms (or is fused with) prime matter. And (after first creation) this prime matter already existed in another body or other bodies before becoming substantially fused with the present substantial form.

Thus prime matter is not a kind of bodily stuff (for kind is a form); it is not an existing mass of matter out of which bodies emerge in determinate individuality under action of the substantial form. It is wholly potential (i.e., aptitudinal; a capacity), and it is described as “pure potentiality.” This potentiality is actualized (i.e., made an existing body) by substantial form, and the substantial unit of matter-and-form is an existing body. The identity of all bodies in bodiliness is owing to prime matter (not actively but passively); the essential differentiation of bodies is due to their respective substantial forms.

Substantial form is the actuating, substantifying, principle of a body. It is the substantial constituent principle which makes a body exist in its essential kind. Substantial form is a substance, — that is, it is a reality suited to exist itself and not to be merely the mark of something else; it is no mere accident, — that is, a reality unsuited to exist in itself and suited to exist as the mark of something else. But substantial form (unless it be spiritual) is not a complete substance; it requires the co-substance called prime matter with which to fuse substantially to constitute an existing body. And yet, it does not stand to prime matter as something separate; for it does not (unless it be spiritual) exist by itself, nor does prime matter exist by itself. The two exist in substantial union; both are partial or incomplete substances; together in substantial fusion or unity they constitute a complete substance; that is, an existing bodily substance.

When a body is substantially changed, — as food, for example, is changed when it is turned into the very substance of the being that digests and absorbs it, — the old substance is not annihilated and a new substance created. Prime matter, in-formed as one body, loses the substantial form of that body, and instantly without lapse of time, is in-formed by a new substantial form. The instantaneous cessation of the old form is called “corruption”; the simultaneous emergence of the new form is called “generation”; or, more precisely, the former substance ceases to be or “corrupts,” and the new substance appears or “is generated.” Corruption and generation are but two views of the one instantaneous substantial change: the corruption of one body is the generation of another or other, and the generation of one body is the corruption of another or others.

Unless a substantial form be spiritual, it is said to be “educed from the potentiality of matter” when a body is generated; and it is said to be “reduced to the potentiality of matter” when a body is corrupted. Prime matter is the bridge, so to speak, which supports substantial change. It is “in potentiality” (or has the capacity) for union with any substantial form that can make it an existing body; when this potentiality is actualized, the form is said to emerge or to be educed from the potentiality of matter. And when a body “corrupts,” that is, loses its substantial form to gain another or other, the ceasing substantial form falls back, so to speak, into the aptitude of matter to have such a form; it is “reduced to the potentiality of matter.”

Prime matter and substantial form are ultimate constituent principle of bodies. Bodies, said Aristotle, are proximately reduced (or analyzed into) certain elements; these are four: air, earth, water, fire. These proximate elements of bodies, by their varied unions, make up the different kinds of bodies we find about us here on earth. But the elements (air, earth, fire, water) are themselves bodies, and are constituted ultimately by prime matter and substantial form. Aristotle’s “elements” are, of course, now known to be inadequate. But the discovery of such proximate elements is the task of laboratory science, not of philosophy.

Aristotle though that the heavenly bodies are made of a purer and superior kind of material than that which enters the constitution of earthly bodies; he thought that the heavenly bodies are naturally incorruptible. The earth, in his opinion, is the most imperfect of bodies, and naturally tends to corrupt, that is, to undergo substantial change. Aristotle held that matter has been produced or caused; it is not self-existent; but he believed it has been produced from eternity.

Aristotle taught, and rightly, that the human soul is the substantial form of the living human being. Indeed, the life-principle (or psyche) is the substantial form of every living body, plant, animal, man. He discerned the fact that man has the activities of plant, of animal, and of reasoning creature; yet he taught that man has but one soul, and that this is the rational soul. Whether Aristotle held that the soul is truly spiritual and immortal is a matter of dispute. It is certain, however, that he denied the pre-existence of souls.

Section 4: Metaphysics

The word metaphysics is not Aristotle’s own. It was used by Andronicus of Rhodes (about 70 B.C.) as a label for those works of Aristotle which were arranged to follow after his treatises on physics; for the Greek meta means “after.” Metaphysics deals with reality, not as limited to this nature (physis) or that, but as viewed apart from material limitations. Its proper scope includes spiritual being and also all being in so far as it can be considered as free from every material determinant and restriction, from all that makes it this or that class or kind. Thus metaphysics does come “after” (or reaches beyond) the more special studies in philosophy which consider (a) material being, as physics does, or (b) logical being, as logic does, or (c) moral being, as ethics does. Metaphysics is the science of non-material real being. It is no airy or imaginative philosophizing about abstractions that no one can understand; it is not something “away up in the air”; it is the deepest philosophy of reality; it is the very heart of philosophy.

The basic idea of metaphysics is that of being (ens in Latin; on in Greek). In this idea all others are rooted, for every idea is the idea of some thing, that is, of some being. Anything that can be thought of as existing in the order of reality, independently of the creatural mind, is real being. Anything that can be thought of as existing in the mind and dependently on the mind (such as, subject, predicate, species — as predicable) is rational or logical being. Anything that can be known in reference to the law which marks the boundary between right and wrong, is moralbeing. Now, logical being and moral being have place and value only in a world of real being. And it is with this world of real being, universally and most penetratingly considered, that metaphysics deals.

The idea of being (and of real being) is transcendental. That is, it soars over the fences of classification. For the idea of being is the idea of being as such, and knows not kinds or sorts.Every being is being, and even the distinction that marks off one class of thing from another is being.

Still the meaning of being is not precisely the same in all references. God is a being, man is a being, a tree is a being, the color of a rose is a being, the distinction between man and tree is a being. But God is infinite, self-existent, necessary being. Creatures are not necessary beings; they are contingent beings, that is they are produced beings and as such are dependent or contingent upon their causes. Of contingent beings, some are substantial (man, tree, rose); some are accidental (color of a rose). Hence, while all things are beings (and real beings in so far as they are existible in the extramental universe) all things are not identical in possessing every implication of the term being. The philosopher expresses this truth in some such way as this: The transcendental idea of being does not apply to its inferiors or subjects (that is, to the things it designates or denotes) in a univocal manner (that is, in precisely the same sense in each case), nor in an equivocal manner (that is, in a manner utterly different and unrelated in any two cases), but in an analogous manner (that is, in a manner partly identical and partly different in various cases). In a word, while all conceivable things are beings, there are classifications of beings on the score of necessity, contingency, substantiality, accidence.

Out of the root-idea of being Aristotle draws certain self-evident truths or “first principles.” The truly first “first principle” in the order of all thought and knowledge is called the principle of contradiction. Now, a principle is a source, in any sense; and a source of knowledge and thought is a guiding truth. The basic guiding truth is this: that a thing cannot be, at one and the same time and under the same aspect, both existent and non-existent. This is the principle of contradiction. It emerges from the idea of being when it is considered as something which cannot simultaneously be nothing. Unless this principle be acknowledged (and it is perforce acknowledged even by those who try to doubt or deny it), all thought and all expression of thought become impossible. For if this principle be fallacious, the very word “fallacious” might also mean “true.”

Out of the principle of contradiction come other self-evident principles, such as the principle of identity and difference (“What is, is; what is not, is not”), and the principle of the excluded middle state (“A thing either is or is not; there is nothing midway or neutral between being and non-being”).

In his metaphysics Aristotle also considers being as cause, being as effect, being as one or in unity; being as true; being as good; being as predicamental (i.e., classified in the categories); being as actual (or existing); being as potential (i.e., capable or apt for existing).

Being as actual (or being in actu) is existing being. Being as potential (or being in potentia) is existible being. A thing is actually what it is; a thing is potentially what it may become. The potentiality of a being is either sheer possibility, and then the being is objectively potential; or the potentiality is the capacity of an existing thing to realize its capabilities which actually exist, and then we have subjective potentiality. A boy is actually a boy; potentially he is a grown man, and this potentiality resides in the boy as in its subject; here we have subjective potentiality. Again, the boy is potentially President of the United States; this is objective potentiality or sheer possibility, for there is not in the boy any natural or arranged direction or drive tending towards such an end.

The more actuality a thing has, the more perfect it is. For the more it is actual the more it is, and the more, so to speak, it has. In other words, the greater the actuality of a thing, the less is its capacity for being perfected. Still more briefly, the greater the actuality, the less the potentiality. Now, as reason sees, there must a a First Being that is entirely actual, with no perfectibility or potentiality about it. Thus Pure Actuality is a name and a definition of God. At the other end of the scale of perfection is unmixed potentiality or pure potentiality; this is a definition of prime matter.

Aristotle indicates that God is the final cause of the universe (that is, the end or goal of all things), and he uses this truth to show further that God is also the first effecting or producing cause of things. Aristotle mentions creatural causes (or secondary causes), and notable among these are certain “separate intelligences” (which we might call spirits or angels) who have change of the heavenly bodies.

Our sketch of Aristotle’s metaphysics is a very thin sketch indeed; in the nature of things, it cannot be complete or very detailed even as far as it goes. It is presented merely to give the student a general grasp of the scope and character of the science of metaphysics, and to afford him or her some opportunity of appreciating the notable work achieved by Aristotle in rounding that science into acceptable form.

Section 5: Ethics

The Greek word ethos which gives us the term ethics is the same in meaning as the Latin mos (stem mor-) which gives us the term morals. It means that which is characteristic of man.Now, the real characteristic of man, his hallmark so to say, is found in the fact that he can act freely, self-directingly, and responsibly. In a word, the distinctive mark of human activity is this: it comes from a free-will. Thus ethics is the science of “free-will actions.”

Now, free-will actions will lie in line with reason or will conflict with reason; they will, in other words, fit harmoniously with the purpose for which man exists, and for which free-will is given to him, or they will clash with that purpose. Accordingly, such actions will be right and good, or they will be wrong and evil. Ethics, therefore, deals with the morality of freely-willed human conduct.

The end an purpose of man’s existence, and the end and purpose to which all his deliberate action ought to be directed, is the good, that is, the boundless good. In the achieving of that good, man is to find the completion of himself, the filling up of every rational tendency and appetency; and this will be his beatitude, his happiness. For the achieving of the boundless good (the summum bonum) and beatitude man must seek to know and love truth and to act in conformity with it. In particular, man must rightly know and appreciate his own character and place and duty as man. An important item in this knowledge is the fact that man is by nature a social being; he lives with others of his kind and has rights and duties in their regard. Man is inclined towards conjugal society or marriage; he requires civil society or the State. As to the form of government in the State, times, circumstances, and temperaments will be the determinants. There is also a master-and-slave society which is useful (and perhaps necessary, Aristotle seems to say) but which does not involve slave-ownership. Master and slave should be friends; slaves must never be subjected to cruel treatment.

Aristotle’s ethics is not a perfect moral science. He omits the necessary eternal sanctions for the moral law. He wrongly supposes that the mastery of slaves is a good, and perhaps a naturally necessary thing. But he is worlds ahead of Plato in his clear discernment that the State is the instrument of the citizens, not their owner. He rightly holds that some civil rule (i.e., the State) is naturally required by men living in society, but that its form is for the citizens to determine.

Summary of Part II of The Development of Philosophy

We have outlined, in Part II, the philosophy of Aristotle, prince of philosophers.

We have seen that Aristotle is the inventor of Logic and have noticed that he also rounded this science into completeness.

In Physics, we have seen the matter-and-form doctrine, known as hylomorphism, as Aristotle’s philosophy of the bodily world. No more acceptable theory of matter (that is, cosmology) has as yet been formulated.

Aristotle was, of course, very deficient in point of experimental physics. His times did not afford the opportunities and the instruments for accurate physical and chemical research.

He assumed as his hypothesis in the matter of experimental science the doctrine of Empedocles on the “four elements,” and so did all philosophers and scientists up to the Middle Ages.

Still, Aristotle’s philosophy of matter is not to be undervalued because of his inadequate knowledge of experimental physics; philosophy does not depend upon the laboratory, even though it uses the findings of science for telling illustration and for direction in its investigations.

Aristotle was not, after all, directly or deeply concerned with the proximate principles of bodies; his was a philosophic quest; he sought ultimate principles.

And the Aristotelian cosmology, while often challenged and questioned, has managed to outlive all objections and objectors; it has held its own for over two thousand years.

Hylomorphism may not be the last word in the philosophy of bodies; it may come to suffer modification and even essential change.

It leaves things to explain, it is not without many difficulties; but its difficulties and deficiencies are neither so many nor so baffling as those involved in the several theories of matter which have tried to supplant it.

In metaphysics Aristotle is on undebatable ground; here true philosophy suffers neither doubt nor hesitation.

We have seen that metaphysics is the philosophical science of non-material real being.

We have noticed the first principles involved in the very concept or idea of being, and we have seen that these principles are the indemonstrable but necessary and indubitable truths upon which all knowledge and all the sciences ultimately depend.

We have discussed the doctrine of actuality and potentiality in being.

In our brief consideration of Aristotle’s ethics we have noted his doctrine of man’s purpose in existence and of the means available for the achievement of that purpose.

We have seen that Aristotle taught, with perfect truth, that man is, by his very nature, a social being; that he is in natural need of civil society or the State; that the State is not the owner of the citizens nor the end for which they exist.

Our vocabulary of philosophical terms and phrases has been enriched as we learned the meaning of:

  • apprehending
  • judging
  • reasoning (or inference)
  • idea (or concept)
  • judgment
  • syllogism
  • deduction
  • induction
  • the predicables (genus, species, difference, property, accident)
  • the predicamentals or categories (substance and the nine accidents)
  • being
  • real being
  • logical being
  • moral being
  • inferiors of an idea
  • transcendental idea
  • univocal predication
  • equivocal predication
  • analogous predication
  • principle
  • first principle
  • actuality
  • potentiality
  • matter
  • form
  • prime matter
  • substantial form
  • hylomorphism