Cosmology. — From its Greek etymology (kosmos world; logos, knowledge or science) the word cosmology means the science of the world. It ought, therefore, to include in its scope the study of the whole material universe: that is to say, of inorganic substances, of plants, of animals, and of man himself. But, as a matter of fact, the wide range indicated by the etymology of the word has been narrowed in the actual meaning. In our day cosmology is a branch of philosophical study, and therefore excludes from its investigation whatever forms the object of the natural sciences. While the sciences of physics and biology seek the proximate causes of corporal phenomena, the laws that govern them, and the wonderful harmony resulting there from, cosmology aims to discover the deeper and remoter causes which neither observation nor experiment immediately reveals. This special purpose restricts in many ways the field of cosmology. There is another limitation not less important. Man's unique position in the universe makes him the object of a special philosophical study, viz. psychology, or anthropology; and, in consequence, that portion of the corporeal world with which these sciences deal has been cut off from the domain of cosmology properly so called.
There is a tendency at present to restrict the field still further; and limit it to what is known as inorganic creation. Psychology being by its very definition the study of human life considered in its first principle and in the totality of its phenomena, its investigations ought to comprise, it would seem, the threefold life of man, vegetative, animal, and rational. And, indeed, the inter-dependence of these three lives in the one living human being appears to justify the enlargement demanded nowadays by many authors of note for the psychological field. Hence for those who accept this view, cosmology has nothing to do with organic life but is reduced to "a philosophical study of the inorganic world". Such, in our opinion, is the best definition that can be given. At the same time it should be remarked that many philosophers still favor a broader definition, which would include not only the mineral kingdom but also living things considered in a general way. In German-speaking countries cosmology, as a rule, is known as Naturphilosophie, i.e. philosophy of nature.
Under this name, philosophers usually understand a study of the universe along the lines of one of the foregoing definitions. Scientists, on the other hand, give a more scientific turn to this philosophy of nature, transforming it into a sort of general physics with an occasional excursion into the realm of sensitive and intellectual life. A notable instance is the work of Prof. Ostwald, "Vorlesungen fiber Naturphilosophie" (Leipzig, 1902).
I. ORIGIN OF COSMOLOGY
The word itself is of recent origin. It was first used by Wolff when, in 1730, he entitled one of his works "Cosmologia Generalis" (Frankfort and Leipzig). In this treatise the author studies especially the laws of motion, the relations that exist among things in nature, the contingency of the universe, the harmony of nature, the necessity of postulating a God to explain the origin of the cosmos and its manifestation of purpose. Because of the advance the natural sciences were then making, Wolff omitted from his philosophic study of nature the purely scientific portion which till then had been closely allied with it. The cosmology of the ancients and especially of Aristotle was simply a branch of physics. The "Physics" of Aristotle treats of corporeal beings in as far as they are subject to motion. The work is divided into two parts: (I) General physics, which embraces the general principles governing corporeal being. It treats of local motion and its various kinds; the origin of substantial compounds; changes in quality; changes in quantity by increase and decrease; and changes arising from motion in place, on which Aristotle hinges our notions of the infinite, of time, and of space. (2) Special physics which deals with the various classes of beings: terrestrial bodies, celestial bodies, and man. It is the first part of this work that comes nearest to what we mean by cosmology. The Schoolmen of the Middle Ages, as a rule, follow the path marked out for them by Aristotle. Cosmological subjects, properly so called, have no reserved place in philosophical study, and are generally treated as a part of physics. In our own time, philosophers employ the words "cosmology" and "philosophy of nature" to designate the philosophic study of the corporeal world.
Cosmology is the natural complement of the special sciences. It begins where they leave off, and its domain is quite distinct from theirs. The scientist determines the immediate cause of the phenomena observed in the mineral or the organic world: he formulates their laws, and builds these into a synthesis with the help of certain general theories, such as those of light, of heat, and of electricity. The cosmologist, on the other hand, seeks the ultimate causes, not of this or that class of beings or of phenomena, but of the whole material universe. He inquires into the constituent nature of corporeal beings, their destiny, and their first cause. It is clear that these larger problems are quite beyond the range and purpose of the various sciences, each of which is by its method confined to its own particular subject. Nevertheless, cosmology must borrow, and borrow largely, from the data of science, since the causes which it studies are not directly perceptible; they can be known only through phenomena which are their more or less faithful manifestations. It is on these that cosmology must rest in order to pass upward from cause to cause till the ultimate cause is reached. Since, then, it is the role of the natural sciences to analyze and classify the properties and phenomena of nature, cosmology is obliged to draw very freely upon those sciences and to neglect none of their definitive results. In a word, the cosmological method is essentially a posteriori. Descartes and his school followed a different, even an opposite, course. Being a mathematician above all else, he applies to cosmology the principles of mathematics, and as mathematics sets out from the simplest propositions and travels along the road of deduction to the most complex truths, so Descartes, starting from extension as the primordial and universal property of matter, in fact its very essence, ends by ascribing to all bodies in nature what-ever extension implies and by eliminating from them whatever it excludes. This a priori method, being essentially deductive is anti-scientific; and is based, moreover, on a false supposition, since extension is only one of the many properties of matter, not its essence. As Leibniz pointed out, extension presupposes something extended, just as a repetition presupposes something to be repeated. Philosophers, therefore, have almost entirely abandoned this method; with the exception perhaps of the Idealistic Pantheists of whom we shall speak presently.
III. DIVISION OF COSMOLOGY
Cosmology, as most philosophers understand it, has a threefold problem to solve: Whence this corporeal world? What is it? Why is it? Hence its three parts, concerned respectively with (I) the primordial efficient cause of the cosmos; (2) its actual constituent causes; (3) its final cause.
A. The first cause of the material universe
Geology, go back as it may and as far as it may in the scientific history of the earth, must ever remain face to face with a fact that calls for explanation, viz. the existence of matter itself. Even if it could decisively prove Laplace's hypothesis, according to which all portions of this universe, earth, sun, and the whole stellar system, originally made up a single nebular mass, there would still remain the very reasonable question, whence came this mass and what was its origin? Now this is precisely the question cosmology asks; and in seeking the answer it has given rise to many systems which can always be brought under one of the following headings: (a) Monism; (b) the theory of Transitive Emanation; (c) Creationism. (a) The Monist theory is that all beings in the world are but one and the same necessary and eternal substance having within itself the sufficient reason of its existence; while the seeming diversity of things and their attributes, are but the various manifestations and evolutions of this single substance. Pantheism identifies the world with the Divine Being. This Being is ceaselessly in process of evolution; which, however, in no wise disturbs the universal identity of things. The Pantheist is either an Idealist or a Realist according to the view he takes of the nature and character of the original substance. If that substance is real he is styled a Realist, and such were Erigena, Amalric, David of Dinant, Giordano Bruno, and Spinoza. But if the original substance is something ideal, e.g. the Ego, the Absolute, the Concept, he is styled an Idealist, and such were Hegel, Schelling, and Fichte. Kraus and Tiberghien support the Pantheistic view: God is in the world and the world is in God, although they are not identical. Schopenhauer devised a form of Pantheism which is known as Panthelism. According to his view the motive force of the whole universe is a single blind will. Hartmann goes a step farther and says the world is but the constant evolution of the unconscious: hence the name Panhylism. Modern Materialists, such as Buchner, Hackel, Baruch, as well as the old Greek Atomists, Leucippus, Democritus, and Epicurus, consider all the activities of the universe as so many purely material phenomena arising from one necessary and eternal substance. Lastly, according to the supporters of the Immanent Emanation theory, the Divine Being develops within itself so that it is continually identifying itself with the beings it evolves, or that come forth from it, just as the grub maintains its substantial identity throughout its transformation into chrysalis and butterfly. It is clear that such a theory hardly differs from Pantheism.
(b) In the Transitive Emanation theory all beings issue from the Divine Substance much in the same way as new fruits appear on the parent tree without changing its substance and without diminishing its productive power. (c) Creationism is the view held by the generality of spiritualistic philosophers. The universe through its endless transformations reveals its contingency: that is to say, its existence is not a necessity: therefore it must have received its existence from some other being. This first cause must be a necessary and independent one, unless we admit an infinite series of dependent causes and so leave unsolved the problem of the world's existence. God has, therefore, drawn all things from nothingness by the free act of His Almighty Will; in a word, He has made them out of nothing, since any other explanation, e.g. Emanationism, which implies a real intrinsic change in God, is incompatible with the immutability, necessity, and absolute perfection of the Divine Being.
B. The constituent causes of the world
The composition of corporeal beings is also the subject of much discussion. There are actually four systems of note, each promising to solve this delicate problem: Mechanism; Hylomorphism (the Scholastic system); Dynamic Atomism; and Dynamism proper.
The characteristic tendency of Mechanism, i.e. of the mechanical theory, is to disregard all qualitative difference in natural phenomena and to emphasize their quantitative differences. That is to say, in this system the constituent matter of all corporeal beings is everywhere the same and is essentially homogeneous; all the forces animating it are of the same nature; they are simply modes of local motion. Furthermore, there is no internal principle of finality; in the world everything is determined by mechanical laws. To explain all cosmic phenomena, nothing is needed but mass and motion; so that all the differences observable between corporeal beings are merely differences in the amount of matter and motion. Mechanism appeals especially to the law of the correlation of forces in nature and of the mechanical equivalent of heat. Heat, we know, does work; but it consumes itself in proportion to its own activity. In like manner mechanical causes produce heat and grow weaker in proportion to the intensity of their effect. So it is with all corporeal energy; one form may be substituted for another, but the quantity of the new force will be always equivalent to the quantity of the force that has disappeared. Having in this way identified mechanical force with motion, the holders of this theory felt authorized to unify all forces and reduce them to local motion; and it was then an easy step to consider substance as homogeneous since its only use is to serve as a background for phenomena. Other arguments are drawn from chemistry, especially from the facts of isomerism, polymerism, and allotropism.
The mechanical theory is of ancient origin. Amongst its earliest partisans were Thales, Anaximander, and Heraclitus, whose chief concern was to prove the derivation of the world from one simple primitive substance. Empedocles, however, held out for four elements—air, earth, water, fire. But Democritus, and later Epicurus, suppressed this distinction between the elements, proclaimed the essential homogeneity of matter, and referred the variety of natural phenomena to differences of motion. After the time of Epicurus (270 B.C.), this system disappeared from philosophical thought for eighteen centuries. Restored by Descartes, it soon won the favor of most scientists, and it is still dominant in scientific research. The Cartesian philosophy was a restatement of the two basic principles of the old theory, the homogeneity of nature and the reduction of all forces to terms of motion; but it got new vigour by contact with the natural sciences, especially physics and chemistry; hence the name Atomism (q. v.) by which it is usually known. It should, however, be noted that there are two Atomisms, the one purely chemical, the other philosophical. According to the former all simple bodies are made up of atoms, i.e. of particles so small that no chemical force known to us can divide them, but which have all the properties of visible bodies. Atoms form groups of two or four or sometimes more; these small tenacious groups, known as chemical molecules coalesce in physical molecules, and from these in turn are built up the material bodies we see around us. The material body thus results from a progressive aggregation of molecules, and the very smallest portion of it that is endowed with the properties of the compound contains many atoms of various species, since by definition the compound results from the union of numerous elements. On this atomic theory, independent as such of all philosophical systems, was grafted during the last century that philosophical Atomism which, while ascribing to all atoms the same nature, differentiates them only by varying amounts of mass and motion.
Another explanation of the material world is offered by Dynamism. If Mechanism attributes extension to matter and complete passivity to corporeal substances, Dynamism sees in the world only simple forces, unextended, yet essentially active. There is nothing strange in the antithesis of these two systems. The Dynamism of Leibniz—it was he who propounded it—was but a reaction against the Mechanism of Descartes. To these two matrix-ideas of unextended, active forces the majority of Dynamists add the principle of actio in distans. They soon found out that points without extension can touch only by completely merging the one with the other, and on their own hypothesis the points in contact would amount to nothing more than a mathematical point which could never give us even the illusion of apparent extension. To avoid this pitfall, the Dynamists bethought them of considering all bodies as aggregates of force unextended indeed but separated by intervals from one another. Conceived by Leibniz, who held the monads to be dowered with an immanent activity, this system has been amended and modernized by Father Boscovich, Kant, Father Palmieri, Father Carbonelle, Hirn, and Father Leroy. On the whole it has found few supporters; scientists as a rule prefer the mechanical view. It would seem, however, that a reaction towards it has set in since the discovery of the radio-activity of matter. The property manifested by a considerable number of bodies of emitting at ordinary temperatures a seemingly inexhaustible quantity of electric rays suggests the idea that matter is a focus of energy which tends to diffuse itself in space. But in point of fact there are only two arguments in favor of Dynamism. One is drawn from the difficulties of grasping the concept of extension; the other from the fact that all we know of matter comes to us through its action on our organs of sense; hence the inference that force is the only thing existing apart from ourselves.
Between these two extremes stands the Scholastic theory, known as Hylomorphism, or theory of matter and form (GKIX,t, matter; pop/n, form), also as the Aristotelean theory, and later as the Thomistic theory from the name of its principal defender in the Middle Ages. Aristotle (384-322 B.C.), who was its author, gave it a large place in his treatises on physics and on metaphysics. It was discussed during centuries in the Peripatetic and neo-Platonic schools and in the schools of Constantinople and Athens; but from the sixth century to the twelfth, though its essential principles survived, it was an insignificant factor in philosophic thought. An exception, however, must be made in favor of Avicenna in the East (980-1037) and of Averroes in Spain (1126-1198), both famous commentators on the Aristotelean encyclopedia. In the thirteenth century, the Golden Age of Scholasticism, the system was restored, thanks to a number of Latin translations, and its long-forgotten treasures were brought to light by daring prospectors, such as Alexander of Hales, Albertus Magnus, St. Thomas Aquinas, St. Bonaventure, and Henry of Ghent. During the fourteenth and fifteenth centuries the cosmological theory, and indeed the whole Scholastic system, suffered a decline which lasted till the nineteenth century, though during the interval it found ardent supporters in some of the religious orders. The restoration movement began about the middle of the nineteenth century with the works of Kleutgen (1811-1883); Sanseverino (1811-1865), and Liberatore (1810-1892); but it was especially owing to the impulse given it by the famous Encyclical of Leo XIII, "Aeterni Patris" (1879), that Scholasticism regained its place of honor beside the great modern systems.
The Scholastic theory can be summed up in the following propositions: (I) Bodies both elementary and compound have an essential unity; they differ specifically, and are by their very nature extended; (2) they possess powers or energies both passive and active which spring from their substantial nature and are inseparable from it; (3) they have an immanent tendency toward certain special ends to be realized by the exercise of their native energies. The basic principle of this cosmology is that of immanent finality. The corporeal world is a masterpiece of order and harmony. In spite of ceaseless transformations, every species of body, simple and composite alike, reappears again and again with its characteristic properties to further the well-being of the individual and of the universe as a whole. Now this constant and harmonious cooperation of innumerable causes acting under conditions the most diverse can only be explained, say the Scholastics, by admitting in the material agents themselves fixed and permanent principles of order. The universe must therefore be composed of specific natures, i.e. of beings which by their constitution and properties are really adapted to the ends they have to attain. Substance and its distinctive energies form a whole which is completely subordinated to its appointed destiny; so that if serious alterations, such as chemical combinations, succeed in affecting these properties and in marring the harmony that ought to exist between them and their substantial base, the being so affected must put on a new nature in harmony with its new state. There takes place, in other words, what the Scholastics call a substantial trans-formation. But this implies that an essential portion of the original being must persist throughout the change, and be carried over into the final result, otherwise transformation would involve the annihilation of the first being and the production of the second out of nothing. On the other hand, if we hold that during the process the being in question does not lose its own specific difference in exchange for another, it would be illogical to speak of a transformation, since a change which preserves the substantial integrity of the being can never have as its result the production of a new being. All bodies, then, that are subject to such a change must contain, in spite of their unity, two constituent principles. The one is a specifying or determining principle whence spring the actuality and distinguishing marks of the body itself; and it is this principle which is born and dies at every step in the deeper transformations of matter. It is called substantial form. The other, the indeterminate complement of this, is the substratum which receives the various essential forms; and it is called first matter. These are the fundamental ideas in the Scholastic theory.
As a system it is not at every point the direct anti-thesis of the two other systems outlined above. It is true that, while Mechanism claims that the proper-ties of bodies are nothing but local motion, the Scholastics admit the existence of qualities properly so called in all bodies, i.e. accidental determinations, fixed and destined for action. These properties are generated with the new substance; they cling to it indissolubly during its existence and they are its natural manifestation. But, on the other hand, the Scholastics concede to the mechanical theory that local motion plays a large part in the world, that it is the accompaniment and the measure of every exertion of material force. Hence they give Mechanism credit for assigning a quantitative value to the phenomena of nature by measuring the movement proportionate to each; while, on their side, they explain the activity at work in each case by taking into account the qualitative elements as well as the kinetic. Again, with the mechanical theory the Scholastic recognizes in every corporeal being an essential principle of passivity, of inertia, divisibility, and extension—in a word, of all the properties so highly prized by Mechanism; this principle is first matter. But the Scholastic theory adds a substantial form, i.e. a determining principle and a root-cause of the activities and peculiar tendencies displayed by each individual body.
A similar partial agreement exists between Scholasticism and Dynamism. In the hylomorphic constitution of bodies the dynamic element has a preponderating role, represented by the substantial form; but since the corporeal being does not appear to be a source of energy pure and simple, the dynamic element is joined with first matter, of which passivity and extension are the natural outcome.
4. Dynamic Atomism
A fourth and last system is called Dynamic Atomism. The only real difference between it and Mechanism lies in the fact that it attributes to bodies forces distinct from local motion; but at the same time it maintains that they are purely mechanical forces. Matter, it asserts, is homogeneous and the atom incapable of transformation. This theory, proposed by Martin and Tongiorgi, and upheld nowadays by certain scientists, is a transition between the mechanical and the Scholastic system. Its partisans, in fact, are persuaded that a theory which denies the reality of qualitative energies inherent in matter and reduces them to local motion thereby makes the true explanation of natural phenomena impossible and hands over the universe to the whims of chance. Some Dynamists, therefore, to meet the obvious requirements of order in the world, seek in substance itself the reasons of its secondary principles of activity. But in this hypothesis it seems rather hard not to admit, as the Scholastics maintain, that diversity of substance is the only explanation of the constancy observed in the accidental differences of things.
C. The final cause of the material universe
The last problem that cosmology attempts to solve is that of the final cause. It is intimately bound up with that of the first cause. Materialists like Hackel and Buchner, who refuse to see in the universe a plan or a purpose, can assign no goal to cosmic evolution. In their opinion, just as the world, during its eternal past, has undergone countless variations in form, so during its eternal future it is destined to ceaseless change. The laws of mechanics, the chance encounter of atoms and molecules, the capricious play of natural forces following no preconceived aim, will determine the number, nature, and form of the states through which matter is to pass. Pantheists and all who identify God with matter share as a rule the same view. For them the condition of the world is but the fatal result of purposeless evolution; so that the world is its own end, or rather is itself the term of its existence and activity.
Those who believe in the existence of a personal God can never admit that an all-wise being created without a purpose. And since a perfect and independent being can have no other than himself as the final aim of his action, it follows that the ultimate end of creation is to manifest the glory of the Creator, man being the intermediary, and, as it were, the high-priest of the material world. The welfare of man himself is the secondary purpose of creation. According to St. Thomas the world is a vast hierarchy of which inorganic matter is the base and man the summit. The mineral order ministers to the vegetable and this in turn to the animal, while man finds in all these the satisfaction of his needs and the adornment of his earthly life. Above all he finds in the material universe and in the service it renders him a means of rising to perfect happiness in the possession of God.