Panpsychism is a philosophical theory which holds that everything in the universe, the inorganic world as well as the organic, has some degree of consciousness.

It is closely related to the theory of hylozoism, which teaches that all matter is endowed with life. As synonymous with hylozoism must be regarded the word panbiotism which was coined by Paul Carus to distinguish his theory from the panpsychism of Häckel ("Monist", 1892-93, III, 234-57). Between panpsychism and hylozoism there is no sharp distinction, because the ancient hylozoists not only regarded the spirits of the material universe and plant world as alive, but also as more or less conscious. The Renaissance witnessed a revival of the ancient hylozoism. The Italian philosophers of nature and the alchemists speculated about the spirits that were present in all things and the "feelings" and "strivings" of the "principles" of nature. The monadism of Leibniz is evidently panpsychistic. All things are made up of monads. Every monad is conscious and mirrors intellectually in itself the entire universe. One monad differs from another only in the clearness with which this mental representation is expressed.

Apart from these early movements there is the modern school of panpsychism, during the development of which the word itself was coined. It began with Fechner (1801-87) and received a new impetus from Darwinian philosophy in England and metaphysical speculation in America.

The panpsychism of Fechner and later German writers is most closely connected with the Renaissance revival of hylozoism. Both Fechner and Lotze have much in common with the mystical speculations of Paracelsus and van Helmont. To Fechner everything is animated; the earth is truly our mother, and a living mother at that. The panpsychism of Lotze (1817-81) arises as a dreamy speculation, rather than a coldly-reasoned conclusion. "Has one half of creation, that which we comprise under the name of the material world, no function whatever save that of serving the other half, the realm of mind, and are we not justified in longing to find the lustre of sense in that also whence we always derive it?" (Microcosmos, I, Book III, ch. iv, p. 353.) By making the atom unextended Lotze thought that he had removed the last objection to his panpsychism. Of a similar type is the panpsychism of Paulsen, and not far removed are the speculations of Häckel on the pleasures and pains of the elements. With G. Heymans panpsychism appears as a reasoned conclusion from a metaphysical consideration of the relation between body and mind.

In England panpsychism was advocated by William Kingdon Clifford as early as January, 1878 (Mind, III, 57-67). He arrived at the theory as a corollary from the doctrine of evolution. Consciousness exists in man; man is evolved from inorganic matter; therefore inorganic matter has in it the elements of consciousness. This conclusion was then extended to the assertion that "the universe consists entirely of mind stuff". As his forerunners in this conception Clifford mentioned Kant and Häckel - and especially Wundt - of whom he wrote: "the first statement of the doctrine in its true connexion that I know of is by Wundt" (Lectures and Essays, II, 73).

In America as early as 1885, Dr. Morton Prince advocated the theory of panpsychism, though not under that name. He looked upon his theory as a vindication of materialism, arguing that if matter is psychical in its nature and mind is to be interpreted as the resultant of these mental forces of nature, such an interpretation must be materialistic; for "as long as anything is the resultant of the forces of nature it belongs to materialism" (The Nature of Mind, 152). His panpsychism was in reality an illegitimate conversion of the proposition: "all conscious processes are physical changes" to "all physical changes are conscious processes". This inference was supplemented by hints at the evolutionary argument of Clifford. While the panpsychism of Clifford and Prince was more or less empirical, that of Prof. C.A. Strong is more pronouncedly metaphysical; it deals with the problem of interaction between body and mind. Prof. Strong proposes to solve it by eliminating the essential distinction between body and soul, in holding that matter itself is psychical rather than physical in its nature. His work, "Why the Mind Has a Body" (New York, 1903) called forth a lively discussion of this theory.

The first article of the eighteenth question in the first part of the "Summa Theologica" of St. Thomas is entitled: "Is every thing in nature alive?" It is a discussion of the theory of hylozoism and tells us also the position of the great scholastic on the question of panpsychism. St. Thomas decides that the test of life is to be sought in the possession of those characteristics that are proper to beings which are most evidently alive. These characteristics he embraces under what he terms the power of spontaneous movement. By this he does not mean the mere capability of moving about from place to place, but any spontaneous tendency towards any kind of change (quoecumque se agunt ad motum vel operationem aliquam). As examples of such motion he mentions the tendency of a thing from a less to a more perfect state (growth), and the sensations and understanding which constitute the activity of animals that have already acquired their full development. The question then becomes one of fact. Are there any things in nature that do not manifest the power of spontaneous movement, i.e. growth or the activity of sensory and intellectual life? Yes. There are things which have no spontaneous activity of their own and do not move except by an impulse from without, and these things are lifeless or dead. We may see analogies in them to living things, but they can never be said to live, except we are speaking poetically and by way of metaphor. St. Thomas therefore rejects hylozoism and panpsychism.

The only serious arguments in favor of panpsychism are: the evolutionary one put forward by Clifford, and the metaphysical reasoning of Prof. Strong. But until there is evidence to show that the chemical elements manifest some kind of mental process, we have no right to say that they do, no matter how much it would aid any theory of evolution, or how easy it might make our metaphysical explanation of the relation between body and mind.

ST. THOMAS AQUINAS, Summa Theologica, I, Q. xiii, a. 1; BAWDEN, The Meaning of the Psychical in Philos, Review, XIII (1904), 298-319; CARUS, Panpsychism and Panbiotism in The Monist, III (1892-93), 234-57; CLIFFORD, Lectures and Essays, II; Body and Mind in Fortnightly Review (Dec., 1874); IDEM, On the Nature of Things-in-Themselves in Mind (Jan., 1878); FECHNER, Zend Avesta (3rd ed., 2 vols., Leipzig, 1906); FLOURNOY, Sur le panpsychisme in Archives de psychologie, IV (1904-05), 129-44; HÄCKEL, The Riddle of the Universe (London, 1900); Our Monism in The Monist, II (1891-92), 481-86; HEYMANS, Zur Parallelismus-frage in Zeitschrift für Psychologie, XVII (1898), 62-105; LOTZE, Microcosmus, tr. HAMILTON AND JONES, I (Edinburgh, 1881), bk. III, iv; PAULSEN, Introduction to Philosophy, tr. THILLY (New York, 1895), bk. I, i, ß 5, 87-111; PRINCE, The Nature of Mind and the Human Automatism (Philadelphia, 1885); The Identification of Mind and Matter in Philos, Review, XIII (1904), 444-51; STRONG, Why the Mind Has a Body (New York, 1903); IDEM, Quelques considérations sur le panpsychisme in Arch. de psychol., IV (1904-5), 145-54.

THOMAS V. MOORE.