Alcmaeon

Greek philosopher and scientist

• Born: c. 510 b.c.e.
• Birthplace: Croton, Magna Graecia (now in southern Italy)
• Died: c. 430 b.c.e.
• Place of death: Unknown

Alcmaeon was one of the earliest Greeks known to have written on medicine and the first to have practiced scientific dissection.

Early Life

Almost nothing is known about the early life of Alcmaeon (alk-MEE-uhn) except that his father’s name was Peirithous and that he was a native of Croton (Greek Crotona), a coastal town inside the “toe” of Italy. Even Alcmaeon’s dates are uncertain. According to Aristotle, he lived during the old age of the philosopher Pythagoras, whose life spanned much of the sixth century b.c.e. and who died about 490 or later. It was once assumed that, as a younger contemporary of Pythagoras, Alcmaeon probably should be placed in the sixth century. It is now widely held, however, largely from the evidence of his ideas, that he probably lived in the fifth century. The evidence at the disposal of modern scholars is not sufficient to fix the date of his lifetime more precisely.

Croton was a Greek city founded by Achaeans from mainland Greece in 710 b.c.e. It had a fine harbor and enjoyed extensive commerce. As a result, it became the wealthiest and most powerful city in Magna Graecia (the Greek name for southern Italy), especially after its forces defeated and destroyed its enemy, the neighboring city of Sybaris, in 510. It boasted the most splendid temple in southern Italy, the temple of Hera Lacinia, which drew large numbers of Greeks to a great annual religious assembly. Croton was renowned for its devotion to gymnastics; one of its citizens, Milon, became the most famous athlete in Greece, having won the victory in wrestling at Olympia six times. Croton is said to have produced more Olympic victors than any other city.

Croton was also the home of a well-known school of medicine, which was perhaps the earliest in Greece and which long retained its reputation. The city enjoyed the distinction of producing the finest physicians in Greece, of whom the most prominent was Democedes, regarded as the best physician of his day (the second half of the sixth century b.c.e.). His fame carried him to Aegina, Athens, and Samos, where he was employed by the tyrant Polycrates, and to Persia (as a prisoner), where he cured both King Darius the Great and his wife, Atossa, before he escaped, returning to Croton to marry the daughter of Milon.

Croton was also known as the home of the philosopher Pythagoras and his followers. Born in Samos, Pythagoras emigrated to Croton about 530, where he formed a religious brotherhood composed of about three hundred young men. Pythagoras quickly gained influence over the political affairs of the city, but growing opposition to his order led to his retirement from Croton. In the second half of the fifth century a democratic revolution resulted in a massacre of nearly all the members of the order. Alcmaeon is said by some ancient authors to have been a disciple of Pythagoras, but it is likely that this belief was based only on inferences from the similarities of some of his doctrines to those of the Pythagoreans. Aristotle compares his theory of opposites with that of the Pythagoreans but says that Alcmaeon either borrowed this idea from them or they took it from him. There is, in fact, no definitive evidence that associates Alcmaeon with the Pythagoreans. He lived during the period in which the Pythagorean brotherhood flourished at Croton, and he probably knew of the Pythagoreans and their beliefs. His precise relationship to them, however, is not known. Diogenes Laertius reports that Alcmaeon wrote mostly on medicine, and it has been inferred from this statement that he was a physician. Given Croton’s reputation as a medical center, it is not unlikely. He wrote on physics and astronomy as well, however, and in this respect he resembles the Ionian philosophers, some of whom were interested in medicine. He was certainly a natural philosopher, interested in science and medicine; he may or may not have been a physician.

Life’s Work

Alcmaeon lived in the pre-Socratic period, when the study of physiology was merely a part of philosophy. Only later did Hippocrates separate medicine from philosophy. Greek medical theory, in fact, grew out of philosophical speculation rather than the practice of medicine. Alcmaeon’s contributions include both cosmological conjecture and anatomical research. He was credited in antiquity with having written the first treatise on natural philosophy. The book is no longer extant, but some idea of its contents can be gleaned from portions that were summarized by later writers. In the opening sentence of the work, Alcmaeon declared that the gods alone have certain knowledge, while for humans only inference from things seen is possible. Thus, he eschewed all-encompassing, oversimplified hypotheses in favor of careful observation as the basis of understanding nature.

Nevertheless, Alcmaeon shared with the Ionian philosophers an interest in natural speculation. Thus, he posited a microcosmic-macrocosmic relationship between humans and the universe. He believed that the human soul was immortal because it was continuously in motion, like the heavenly bodies, which he thought divine and immortal because they moved continuously and eternally in circles. While the heavenly bodies are immortal, however, humans perish because “they cannot join the beginning to the end.” Alcmaeon seems to mean by this that human life is not circular but linear and thus is not eternally renewed but runs down and dies when its motion ceases.

Alcmaeon developed a theory of opposites, according to which human beings have within them pairs of opposing forces, such as black and white, bitter and sweet, good and bad, large and small. He may well have been indebted to the Pythagoreans, who posited pairs of contrary qualities on mathematical lines (or they may have borrowed the notion from him). Alcmaeon, however, applied his theory particularly to health and disease. He defined health as a balance or equilibrium (isonomia) of opposing forces in the body (for example, warm and cold, bitter and sweet, wet and dry). He explained disease as the excess or predominance (monarchia) of one of these qualities or pairs of opposites that upsets the balance. This predominance could be caused by an excess or deficiency of food or by such external factors as climate, locality, fatigue, or exertion. Alcmaeon probably based this theory on his observation of factional struggles in Greek city-states, and he may have been influenced by the growth of democratic political ideas. Of all Alcmaeon’s theories, this concept of opposites was to be the most influential in later Greek thought. The Hippocratic treatise Peri archaies ietrikes (c. 430-400 b.c.e.; On Ancient Medicine, 1849) defends and elaborates on this explanation.

Alcmaeon’s theoretical speculation was balanced by a notable empirical tendency. It is this mixture of theory and observation that gives his work a distinctive and even pioneering nature. Alcmaeon, like many pre-Socratic philosophers, was interested in physiology, but he appears to have been the first to test his theories by examination of the body. In a celebrated case, he cut out the eye of an animal (whether dead or alive is uncertain). He was apparently interested in observing the substances of which the eye was composed. Whether he dissected the eye is not known. He also discovered (or inferred the existence of) the channels that connect the eye to the brain (probably the optic nerves).

There is no evidence that Alcmaeon ever dissected human corpses, and it is unlikely that he did so. He believed that the eye contained fire (which could be seen when the eye was lit) and water (which dissection revealed to have come from the brain). He concluded that there were similar passages connecting the other sense organs to the brain, and he described the passages connecting the brain to the mouth, nose, and ears (and quite possibly was the first to discover the Eustachian tubes). He thought that these channels were hollow and carried pneuma (air). Alcmaeon concluded that the brain provided the sensations of sight, hearing, smell, and taste, for he noticed that when a concussion occurred, the senses were affected. Similarly, when the passages were blocked, communication between the brain and the sense organs was cut off. Plato followed Alcmaeon in holding that the brain is the central organ of thought and feeling, but Aristotle and many other philosophers continued to attribute that function to the heart. Alcmaeon also differed from most contemporary philosophers in distinguishing between sensation and thought. He observed that sensation is common to all animals, while only humans possess intelligence.

According to Alcmaeon, whether the body was awake or asleep had to do with the amount of blood in the veins. Sleep was caused by the blood retiring to the larger blood vessels, while waking was the result of the blood being rediffused throughout the body. Alcmaeon was also interested in embryology, and he opened birds’ eggs and examined the development of the embryos. He believed that the head, not the heart, was the first to develop. He resorted to speculation rather than observation in holding that human semen has its origin in the brain. He explained the sterility of mules by the theory that the seed produced by the male was too fine and cold, while the womb of the female did not open, and hence conception was prevented.

Significance

Alcmaeon is recognized as an important figure in the development of the biological sciences in ancient Greece. Although few details regarding either his career or his scientific methods are known, it is clear that he exercised considerable influence on subsequent Greek writers in the fields of medicine and biology. He introduced ideas that were later elaborated by Empedocles, Democritus, several Hippocratic writers, Plato, and Aristotle, among others. His idea that health is a balance of opposing forces in the body, although later modified, was accepted for many hundreds of years. Alcmaeon has often been called the father of embryology, anatomy, physiology, and experimental psychology. While such titles may be unwarranted, in each of these areas Alcmaeon did make significant contributions.

Regardless of whether Alcmaeon was a physician, he was one of the earliest Greeks to formulate medical theories. Many of his ideas were speculative and borrowed from earlier philosophers. Although influenced by the Pythagoreans, he avoided their mysticism, and he recognized the limitations of scientific inference. His medical theory did not grow out of medical practice but always retained a close affinity with philosophy; such theories tended to have little influence on the general practice of Greek medicine. Still, Alcmaeon’s anatomical investigation (particularly his dissection of the eye) and his recognition that the senses are connected with the brain established him as a genuine pioneer in the development of Greek medical science.

Bibliography

Codellas, P. S. “Alcmaeon of Croton: His Life, Work, and Fragments.” Proceedings of the Royal Society of Medicine 25 (1931/1932): 1041-1046. A brief but comprehensive discussion of Alcmaeon’s life and contributions, published by the Royal Society of Medicine’s Section on the History of Medicine.

Gross, Charles G. Brain, Vision, Memory: Tales in the History of Neuroscience. Cambridge: Massachusetts Institute of Technology Press, 1998. Alcmaeon is credited as the first neuroscientist because he correctly described the brain as the site of both cognition and sensation.

Guthrie, W. K. C. A History of Greek Philosophy. Vol. 1. New York: Cambridge University Press, 1978-1990. Includes a discussion of the evidence for Alcmaeon’s dates and an examination of his medical, physiological, and cosmological theories (particularly his doctrine of the soul) by a leading expert on Greek philosophy.

Jones, W. H. S. Philosophy and Medicine in Ancient Greece. 1946. Reprint. New York: Arno Press, 1979. Provides translations of the most important sources for Alcmaeon’s life and doctrines and discusses Alcmaeon’s relationship to Plato and Aristotle.

Lloyd, Geoffrey. “Alcmaeon and the Early History of Dissection.” Sudhoffs Archiv 59 (1975): 113-147. A detailed examination of the evidence for Alcmaeon’s use of dissection, which Lloyd believes Alcmaeon to have practiced in a very limited manner rather than systematically. Explores as well the history of early Greek dissection after Alcmaeon.

Sigerist, Henry E., ed. Early Greek, Hindu, and Persian Medicine. Vol. 2 in A History of Medicine. New York: Oxford University Press, 1987. A general discussion of Alcmaeon and his work in the context of early Greek medicine and philosophy. Valuable for its general treatment of Greek medicine and its background.