Page:Mind (New Series) Volume 9.djvu/236

 222 CHABLES S. MYERS : occurs the passage, "What causes the body to be alive?" and the reply is that it is the soul and always the soul that carries life with it wherever it enters. Soul is divided by Plato into Eeason, Courage and Desire, respectively seated in the head, the breast, and the lower regions. He divides the soul into two mortal (noble and ignoble) parts and an immortal part, the dwelling-places of which in the body, like the bed-chambers of men and women within the house, are kept separate. Plato ascribes to the Soul immortality, transmigration, pre-existence and recollection (&vdfui0'K). He bases its immortality on its survival from evil which kills all else. He is probably serious in adopting the Pythagorean theory of transmigration. The doctrine of recollection by the Soul of its former experiences forms -a necessary support for the development of the Platonic conception of ideas (2). In Plato's pupil, Aristotle (884-322 B.C.), is seen for the first time a dim possibility of the ultimate separation of metaphysical from scientific method. By his collection of diverse scattered physiological phenomena, he laid the founda- tion of a science whose scope and object were finally clearly recognised. Aristotle, after criticising Plato's system, seized on the difference between the potentiality of Matter and the Actuality of Form, and proclaimed that all substances have arisen from the combination of Matter (TO vTroiceifjievov) and Form (TO ri fy elvai). Life, says Aristotle, has substance, and the Form of Life is the Soul. Everything possessing a Soul is alive; the Soul is the principle of movement, without admitting in itself of movement. The hypothesis of the union of Soul with Body is discarded. In the System of Aristotle the latter serves merely as an end to the former. Mankind is distinguished by a vovs, a part of the Soul, unlike the other parts in its immutability and knowing neither birth nor death. The soul has its seat in the Pneuma (which is the cause of vital heat) and resides in the heart. The plant has but one Soul, the Constructive Soul ; the animal has the additional Souls of Desire, Sensation and Locomotion. Finally in man is consummate the Soul of Eeason. The combined influence of Aristotle and Plato on the followers of the Hippocratic school led to a gradual develop- ment of the infant doctrine of the pneuma. Herophilus (fl. 300 B.C.) taught that the pneuma produces four kinds of movement, two of contraction and two of dilatation, and that correspondingly there are four powers (8vi>a/aet?) of animal life, nourishment in the liver, warmth in the heart, thought in the brain and sensation in the nerves. His contemporary, Erasistratus (fl. 250 B.C.), distinguished a TTvevp-a fam/ew in