Aristotle

ARISTOTLE (384-322 B.C.), a great Greek naturalist and natural philosopher; he came from a medical family; at 17, he entered Plato's school, the Academy, in which he remained as a student and collaborator for 20 years. In 343, he took the position of tutor to Alexander the Great; in 355, he returned to Athens and founded his own school, the Lyceum. It can be considered established that Aristotle was not a physician and could have had only theoretical knowledge of medicine; the book on medicine attributed to him has not survived, but in Aristotle's school, they were undoubtedly interested in medicine, and Aristotle's student, Menon, with the assistance of Aristotle, wrote the first history of medicine, having collected the opinions of old physicians. Fragments of this history have survived, as Diels proves, in the papyrus published by him, known under the name Anonymus Londinensis. Aristotle had no direct influence on medicine, but his natural-scientific works and the natural philosophy he developed, in which a large place was allotted to the doctrine of the organism, undoubtedly had a great indirect influence, which continues to this day. Aristotle is justly considered the creator of the sciences of animals—systematics, embryology, comparative anatomy with a physiological bent, and psychology. He collected a vast amount of factual material, partly from old authors, whom he knew perfectly, but, mainly, on the basis of observations made in the Lyceum; this material was developed in detail, systematized, and arranged in accordance with the foundations of his philosophy. Aristotle's doctrine of the organism is as follows: every body, natural and artificial, is composed of matter and form, which makes the object what it is; a bronze statue, for example, can serve as an example. In complex bodies, simpler bodies serve as matter; but matter in a pure, unformed state (prime matter) is unknown to man. Organisms have a threefold composition: 1) at the base lie the elements (earth, water, air, fire, which themselves, according to Aristotle, are composed of the hot, cold, dry, moist); 2) the elements serve as matter for homogeneous parts (fluids and tissues); 3) from them are composed heterogeneous parts (organs). From the organs, the whole—the organism—is composed, with the soul being the highest form. For Aristotle, the soul is not a substance and cannot exist without the organism; it is the forming, realizing principle (entelechy)—a process or act. The organism arises by the forming of maternal mucus by semen; in the spontaneous generation of lower animals, the environment provides the form. Driesch considers Aristotle the founder of vitalism, although this is far from corresponding to reality, and the term 'entelechy,' which has now received such wide fame, is knowingly used by Driesch in a completely different sense to denote a non-material agent (see Vitalism). Aristotle was not an evolutionist, since he believed in the eternity of forms, but his doctrine of the stepped arrangement of living beings according to the height of organization provided a preliminary scheme for the evolutionary doctrine. In particular, it should be noted that in Aristotle, one encounters for the first time a developed doctrine of simple parts, tissues, i.e., of histology without a microscope (see Histology).