Materialism may be defined as that system of philosophy which considers matter as the fundamental principle of all things, and consequently denies absolutely the independence and autonomy of the spirit. It is sometimes considered as synonymous with Naturalism, yet this is erroneous, for there is a difference between the notions of nature and matter. It is also called by some Sensualism, which is more correct, yet only expresses one of the characteristics of the theory of materialism. In a more extended sense, the expression materialism is made to signify the whole of the practical results which, consciously or unconsciously, flow from such philosophy, and whose final object, although sometimes restrained by considerations of prudence or expediency, is sensual enjoyment in its fullest sense.
Materialism, strictly viewed, is the doctrine that all spirit, so called, is material in its substance, and is subject to the laws which govern the composition of material particles and the activity of material forces. Strictly construed, it is a psychological doctrine or theory; but, as it implies certain philosophical assumptions or principles, it makes a place for itself in the domain of speculative philosophy. Its assumptions and conclusions are also fundamental to theology. If its positions are tenable, theology is impossible. If the human soul is but another name for an aggregation of material particles, it cannot exist when these particles are sundered. Although it is conceivable that these particles may be so minute as not necessarily to be disturbed by the dissolution of the larger particles which constitute the body, yet this is too improbable to relieve the materialistic theory from the charge of being inconsistent with the possibility of a future life. The moral relations of the soul must be entirely inconsistent with its subjection to the laws whichs govern matter ands its activities, and these moral relations give to theology — certainly to Christian theology — all its interest. If the assumptions of materialism are correct, there can be no intelligent and personal Creator. Creation itself is inconceivable, and therefore impossible.
A significant fact, which strikes one at first on the study of the history of materialism, is that it never appears as a power among the masses in the early stages of civilization. On the contrary, we find that in all nations a more or less perfect spiritual contemplation of nature forms the first step towards religious consciousness. This fact is a sufficient answer in itself to the assertion that materialism is the original and true form of human consciousness. On the other hand, we find materialism spreading among the masses in the nations which have attained the culminating point of their civilization. It becomes, then, the premonitory sign of their downfall, being already an evidence of their moral and spiritual decay.
The materialistic theory was in some sense sanctioned by those earlier Greek philosophers who referred the origin of all things — the spirit of man included — to some attenuated form of matter, as water, air, or fire. From these rude speculations philosophy emerged by successive efforts, till in the Socratic school the soul of man was held to be distinct in its essence from matter, to be superior to matter, and indestructible by the dissolution of the body. The Socratic school also emphasized the doctrine that mind has infused order into the universe. The Platonic philosophy enforced these doctrines with glowing appeals to the nobler sentiments, and embellished them with a great variety of mythological representations. Aristotle, more cautious and exact in his statements, asserted for the higher forms of intellectual activity an essence distinct from matter. The philosophers of the Epicurean school were avowed materialists. They taught explicitly and earnestly the doctrine that what is called the soul is composed of atoms, and must necessarily be dissipated at death. The universe itself likewise consists of atoms, and all its phenomena are the results of fortuitous combinations of atoms. Sensation, intelligence, and desire are the effects of the action and reaction of the atoms within and the atoms without the body. These doctrines are elaborately set forth by the celebrated Lucretius (B.C. 95-44) in his poem De rerum natura. The Atomic Materialism of Epicurus, and the Imaginative and Rational Spiritualism of Plato and Aristotle, separated the Greek philosophers into two leading divisions, with various unimportant subordinate sections. Among the Jews, the Sadducees denied thlat there was either angel or spirit, or existence after death; but there is no evidence that they supported these doctrines by any philosophical materialistic theories. The Christian philosophy was necessarily antimaterialistic. With the revival of learning and of the ancient philosophies, the Epicurean materialism found many adherents, against whose influence the pronounced. spiritualism of Descartes furnished a positive and most efficient check. Hobbes was the opponent of Descartes, and all his conceptions of the soul and of the laws of its activity are materialistic, reducing all spiritual phenomena to bodily motions. Spinoza made spiritual beings to be modes of the universal substance which is Gods — every spiritual operation being the necessary counterpart of some materialistic phenomenon. But the rise of the mechanical or new philosophy of nature, to which Descartes incidentally contributed, and which Sir Isaac Newton so triumphantly established, had no little influence in developing the materialism of modern philosophy. The speculations of Locke indirectly furthered this tendency; although, with Descartes, he asserted the authority of consciousness for the reality of spiritual phenomena. But still he contended, as against Descartes, that no man has the right to affirm that God could not endow matter with the capacity to think. The free-thinking Deists of England, who called themselves the disciples of Locke, were in many cases materialists, and advanced their speculations against the possibility of a separate existence of the soul in connection with their attacks upon the Christian doctrine of to resurrection. There were few advocates of philosophical materialism among the English writers of the 18th century. David Hartley (1704-1757) made many phenomena of the soul to depend on vibrations of the brain, but expressly denied the inference that the soul is material in its substance. Joseph Priestley (1733-1804) was led, in the course of his speculations, to assert that the soul is nothing but the organized body, and that this doctrine is essential to the rational acceptance of the Christian system (Disquisitions relating to Matter and Spirit, Lond, 1777, 2 vols. 8vo). In France the influence of the spiritualistic doctrines of Descartes was gradually displaced in the schools by the system of Condillac, which found its logical termination in the extreme materialism of La Mettrie (1709-1751). L'Homme machine; Histoire naturelle de l'ame, and of baron Holbach (1723-1789), Systeme de la Narture, in which all spiritual essence and activity are resolved into matter and motion. Here the Encyclopaedists Diderot (q.v.) and D'Alembert (q.v.) deserve special mention; nor should the noted Helvetius (q.v.) be forgotten.
In more recent times, materialism has been both metaphysical and physiological. Metaphysical materialism has resulted in some cases by logical deduction, or, rather, a logical tendency, from the idealistic assumption that matter and spirit are identical. The argument which seeks to make matter and spirit one, lends plausibility to the conclusion that it is indifferent whether matter should be resolved into spirit, or spirit resolved into matter. The extreme idealism of some of the German schools has prepared the way for the materialism with which they would seem to have had the least possible sympathy. The real pantheism of Spinoza and the logical pantheism of Hegel have furnished axioms and a method, which have been applied in the service of materialism. It is in physiology, however, that modem materialism has found its most efficient ally. Physiology has renewed the previously-exploded doctrine of vibrations, which again has found confirmation in that view of the correlation of forces which resolves every agency of nature into some mode of motion. If heat, and light and electricity are but modes of motion, why not nervous activity? and if nervous activity, why not vital energy? and if vital energy, why not spiritual judgments and emotions? This argument has been urged with great earnestness and pertinacity by certain physiologists both of the German and English schools. Conpicuous among them are Carl Vogt, Physiologische Briefe fur Gebildete; Kohler-Glaube und Wissenschafj, 1855; J. Moleschott, Physiologie des Stoffwechsels; Der Kreislau' des Lebens, etc.; Louis Buchner, Kraft und Stoff (1855); Natur u. Geist, etc.; Hackel, NaturlichScrhsoyfungsgeschichte; Ueber die Entstchungq und den Staunzbau des Menschengeschlechts, etc. T. H. Huxley, On the Physical Bases of Life, edit. 1868 (compare J. H. Sterling, As regards Protoplasnm, etc., edit. 1869-72), and H. Maudsley, Physiology and Pathology of the Hlumanz Miind (Lond. and N.Y. 1867), approximate to the same opinions among the English. Alexander Bain (The Senses and the Intellect, Lond. 1855, 1864); The Emotions and the Will, 2d ed. 1865; Mental and Moral Science, Lond. 1867) sympathizes with these tendencies, treating the soul in the main as though it were but a capacity in the nervous system for special functions which obey physiological laws. The doctrine of evolution by natural selection in the struggle for existence, which has been derived by the celebrated Darwin from a limited cycle of physiological facts, and extended by him to explain the production of all complex forms of being, inorganic and organic, is materialistic in its assumptions and its conclusions, even if neither of these are recognized or confessed by its advocates. The metaphysical doctrine of development by successive processes of differentiation and integration, which has been hardened into an axiom by Herbert Spencer, and applied to the explanation of all forms of being, and even of the primal truths of metaphysical science itself, can lead to no other than a materialistic psychology. The doctrine of unconscious cerebration, which is taught more or less explicitly by Dr. W. 1B. Carpenter and other eminent physiologists, though not necessarily involving the materialistic hypothesis, is yet materialistic in its tendencies and associations. The positive school of Comte teaches directly that the brain is the only substance of the soul, and that what are usually called spiritual activities are simply biological phenomena. J. S. Mill, though not avowedly a materialist, follows Hume in reducing matter and mind to idealistic formulae, which, as conceived by him, are not distinguishable from physiological phenomena or products.
According to the materialistic philosophy, as developed by whatever writer, but especially in its once popular form of Epicureanism, the perception of our senses is the only source of all human knowledge. The remembrance of many previous perceptions of the same nature gives rise to general views, and the comparison of these to judgments. Ethics are thus but the doctrine of happiness, and its highest maxim: Seek joy, avoid pain! Yet Epicurus sought to give a certain moral tendency to this fundamental axiom of his system, by declaring every pleasure objectionable which is followed by a greater unpleasantness, and every pain is desirable which is followed by a greater pleasure; according to which principle freedom from care and insensibility to bodily pain become the highest aim of man. See Lutterbeck, Neutestamentliche Lehrbegrinle (Mainz, 1852), 1:38-58; H. Ritter, Gesch. d. Philosophie; Fries, Gesch. d. Philosophie, vol. 1. SEE EPICIUREAN PHILOSOPHY. In Boston a paper entitled The Investigator is now published in the interests of materialism. The German-Americans are also quite active in this work. They have two papers — the Pionier (Boston) and the Neue Zeit (New York). The editor of the former, Karl Heinzen, is frequently before the public all over the country to press the interests of his abominable work. Recently Dr. G. C. Hiebeling published a pamphlet entitled Naturwissenschaft gegen Philosophic (New York, Schmidt, 1871, 12mo) to controvert Hurtmann's Philosophy of the Unknown.
The defects of the materialistic hypothesis are manifold. It considers only the similarities, and overlooks the differences of two classes of actual phenomena. Through its overweening desire of unity, it becomes one-sided and imperfect in all its conceptions and conclusions, and fails to do justice to the peculiarities of spiritual experiences, which are as real as the more obtrusive and palpable phenomena of matter. Moreover, it fails to discern that the intellectual and moral functions not only have a right to be recognized in their full import, but that they have a certain supremacy and authority over all others, inasmuch as the agent which knows must furnish the principles and axioms which all science assumes and on which all science must rest. If the soul is only a function of matter, then to know is one of the functions of matter. It follows that the authority of knowledge itself may be as changeable and uncertain as the changes of form, the varieties of motion, the manifold chemical combinations, or the more or less complex developments of which matter is capable. The materialistic hypothesis not only overlooks and does injustice to the facts which are open to common apprehension, but it is a suicidal theory, which destroys, by its own positions and its method, the very foundations on which any science can stand — even the scientific theory of materialism itself. SEE SOUL.
Literature. — Lange (Frdr. A.), Gesch. des Materialismus, etc. (Iserlohn, 1867, 8vo); Schaller, Leib. u. Seele (3d. ed. 1858); Wagner, Kanmpf um die Seele (1857); Frauenstadt, Der Materialismus; Fabri (Dr. Friedrich), Briefe gegene den Materialisnmus (Stuttg. 1856; 2d ed. 1864, 8vo; comp. Bibl. Sac. 1865, p. 525); Janet, The Materialism of the Present Day (a critique of Dr. Buchner, Lond. and N. Y. 1866, 12mo); Lotze, Medicinische (Leipsic, 1852); also his Mikrokosmus (Leipsic, 1856); Ulrici, Gott und die Natur (Leipsic, 1862); also his Gott und der Mensch (Leipsic, 1866); Fichte, Zur Seelenfr(sqge (Leipsic, 1859); Seelenfoitdauer, etc. (Leipsic, 1867); Psychologie (Leipsic, 1864); Trendelenburg, in the Denkschriften d. K. A kad. (1849); also Hist. Beitriye (1855); Jahr, Die wvichtigsten Zeitfragen; Die Natur, der slenschengeist und sein Gottesbe.grif (Leipsic, 1869, 8vo); Weiss (Dr. L.), Anti-Materialisnzus; Vortrgye aus dens Gebiete der Philosophie (Berlin, 1869, 1871, 2 vols. 8vo); Hagenbach, Hist. of Doctrines, 2:222, 475; Pearson, On Infidelity; Farrar, Crit. Hist. of Free Thought; Buckle, Hist. of Civilization; Mansel, Limits of Religious Thought, Lect. v; Porter, Humnan Intellect, p. 18 sq.; Liddon, Our Lord's Divinity, p. 451; Cudworth, Intellectual Systems of the Universe; Leckey, Hist. of Rationalism; Hamilton, Discussions; Fichte, in the Zeitschr.f. die Philosophie, 1860; Christ. Exam. 1859 (Nov.); North Brit. Rev. 1860 (Nov.); Amer. Presb. Rev. 1869, p. 193; 1872, p. 194; Bibl. Sac. 1860, p. 201; 1865 (July); Theol. Eclect. 1869 (Nov.), p. 55; Princet. Rev. 1869 (Oct.), p. 616; Kitto, Journ. Sac. Lit. 25:25; Westminzster Rev. 1864 (July), p. 90; 1870 (Oct.), p. 225; Rosenkranz, in Zeitschr.fiir wissenschafl. Theol. 1864, vol. iii, art. i; Journ. Specul. Philippians vol. i, No. 3, art. vi; Catholic World, 1870 (Aug.). SEE MATTER. (N. P.)