Queries concerning the soul.
Galen is also at a loss concerning the existence and substance of the soul. He points out that puppies try to bite before their teeth come and that calves try to hook before their horns grow, as if the soul knew the use of these parts beforehand. It might be argued that the soul itself causes the parts to grow,[660] but Galen questions this, nor is he ready to accept the Platonic world-soul theory of a divine force permeating all nature.[661] It offends his instinctive piety and sense of fitness to think of the world-soul in such things as reptiles, vermin, and putrefying corpses. On the other hand, he disagrees with those who deny any innate knowledge or standards to the soul and attribute everything to sense perception and certain imaginations and memories based thereon. Some even deny the existence of the reasoning faculty, he says, and affirm that we are led by the affections of the senses like cattle. For these men courage, prudence, temperance, continence are mere names.[662]
No supernatural force in medicine.
In commenting upon the works of Hippocrates, Galen insists that in speaking of “something divine” in diseases Hippocrates could not have meant supernatural influence, which he never admits into medicine in other passages. Galen tries to explain away the expression as having reference to the effect of the surrounding air.[663] Thus while Galen might look upon nature or certain things in nature as a divine work, he would not admit any supernatural force in science or medicine, or anything bordering upon special providence. In the De usu partium Galen states that he agrees with Moses that “the beginning of genesis in all things generated” was “from the demiurge,” but that he does not agree with him that anything is possible with God and that God can suddenly turn a stone into a man or make a horse or cow from ashes. “In this matter our opinion and that of Plato and of others among the Greeks who have written correctly concerning natural science differs from the view of Moses.” In Galen’s view God attempts nothing contrary to nature but of all possible natural courses invariably chooses the best. Thus Galen expresses his admiration at nature’s providence in keeping the eyebrows and eyelashes of the same length and not letting them grow long like the beard or hair, but this is because a harder cartilaginous flesh is provided for them to grow in, and the mere will of God would not keep hairs from growing in soft flesh. If God had not provided the cartilaginous substance for the eyelashes, “he would have been more careless, not merely than Moses but than a worthless general who builds a wall in a swamp.”[664] As between the views on God of Moses and Epicurus, Galen prefers to steer a middle course.
Galen’s experimental instinct.
Already in describing Galen’s dissections and tests with the pulse we have seen evidence of the accurate observation and experimental instincts which accompanied his zest for hard work and zeal for truth. In one of his treatises he confesses that it was a passion of his always to test everything for himself. “And if anyone accuses me of this, I will confess my disease, from which I have suffered all my life long, that I have trusted no one of those who narrate such things until I have tested it myself, if it was possible for me to have experience of it.”[665] Galen also recognized that general theories were not sufficient for exact knowledge and that specific examples seen with one’s own eyes were indispensable.[666] He maintains that, if all teachers and writers would realize and observe this, they would make comparatively few false statements. He saw the danger of making absolute assertions and the need of noting the particular circumstances of each individual case.[667] Galen more than once declared that things, not names, were important and refused to waste time in disputing about terminology and definitions which might be spent in “pursuing the knowledge of things themselves.”[668] Thus we see in Galen a pragmatic scientist intent upon concrete facts and exact knowledge; but at the same time it must be recognized that he accepted some universal theorems and general views.
Attitude towards authorities.
Galen did not believe in merely repeating in new books the statements of previous authorities. Ever since boyhood, he writes in his Anatomical Administrations, it has seemed to him that one should record in writing only one’s new discoveries and not repeat what has been said already.[669] Nevertheless in some of his writings he collects the prescriptions of past physicians at great length, and a previous treatise by Archigenes is practically embodied in one of Galen’s works on compound medicines. On another occasion, however, after stating that Crito had combined previous treatises upon cosmetics, including the work of Cleopatra, into four books of his own which constitute a well-nigh exhaustive treatment of the subject, Galen says that he sees no profit in copying Crito’s work again and merely reproduces its table of contents.[670] On the other hand, as this passage shows, Galen thought that the ancients had stated many things admirably and he had little patience with contemporaries who would learn nothing from them but were always ambitiously weaving new and complicated dogmas, or misinterpreting and perverting the teachings of the ancients.[671] His method was rather first to “make haste and stretch every nerve to learn what the most celebrated of the ancients have said;”[672] then, having mastered this teaching, to judge it and put it to the test for a long time and determine by observation how much of it agrees and how much disagrees with actual phenomena, and then embrace the former portion and reject the latter.
Adverse criticism of past writers.
This critical employment of past authorities is frequently illustrated in Galen’s works. He mentions a great many names of past physicians and writers, thereby shedding some light upon the history of Greek medicine; but at times he criticizes his predecessors, not sparing even Empedocles and Aristotle. Although he cites Aristotle a great deal, he declares that it is not surprising that Aristotle made many errors in the anatomy of animals, since he thought that the heart in large animals had a third ventricle.[673] As we have already seen in discussing the topic of weights and measurements, Galen especially objects to the vagueness and inaccuracy of many past medical writers,[674] or praises individuals like Heras who give specific information.[675] He also shows a preference for writers who give first-hand information, commending Heraclides of Tarentum as a trustworthy man, if there ever was one, who set down only those things proved by his own experience.[676] Galen declares that one could spend a lifetime in reading the books that have already been written upon medicinal simples. He urges his readers, however, to abstain from Andreas and other liars of that stamp, and above all to eschew Pamphilus who never saw even in a dream the herbs which he describes.