October 25. 1900] 



NATURE 



611 



the authority of the Faith, so was that of Plato ; and, in the 

 second period of the Nliddle Ages, of the Arabian versions 

 of Aristotle and Galen. It is not easy for us to realise a time 

 when intellectual progress, which involves the successive 

 abandonment of provisional syntheses, was unconceived ; when 

 truths were regarded as absolute ; when reasons were not tested 

 but counted ; when even Averroists found final answers either in 

 Aristotle or in Galen. Thus in the irony of things was Harvey 

 withstood by the dogma of that Galen who, in his own day, had 

 earnestly appealed from dogma to nature. 



In the Isagoge of Porphyry is set forth distinctly a problem, 

 which during the Middle Ages rent Western Europe asunder ; a 

 problem, says John of Salisbury, which engaged more of the 

 time and passions of men than for the house of Cresar to con- 

 quer and govern the world ; a problem, indeed, which in our 

 own day is not wholly resolved. This was the controversy of the 

 Realists and Nominalists, first brought to a clear issue by 

 William of Champeaux and Roscellinus respectively. Now Plato 

 held ideas not as mere abstractions but as creative forces ; and 

 we shall see how potent was this function in mediaeval thought. 

 Every particular, every thing, was regarded by the realist as the 

 product of universal matter and individual form. Now form 

 might be regarded, and variously was regarded, as a shaping, 

 determinative force or principle, pattern or mould, having a real 

 existence apart from stuff; or, on the other hand, as an abstract 

 principle or pattern having no existence but as a conception of 

 the mind of the observer. And for the Realist, not individuals 

 only, but genera and species also have their forms ; either pre- 

 existent {iiniversalia ante rem) or continuously evolved in the 

 several acts of creation {universalia in re). For instance, 

 the Church for the Realist is a thing apart from the wills of 

 successive generations of individual men ; Man has fallen, not 

 only in many or all individual cases, but also as a kind— a kind 

 having an independent existence ; in the Sacraments again 

 there may be a change of hypostasis without change in sensible 

 matter. Now, if forms pre-exist (ante rem), the will of God 

 must be predetermined; or if form be an immanent function 

 acting in re, we are landed in pantheism. Thus Erigena, the 

 brilliant prophet and protestant of the first period of the 

 scholastic philosophy, was virtually a pantheist, as Spinoza was 

 the last great realist. Aquinas, who determined the philosophy 

 now ruling in Rome, brought about a compromise, which covers 

 up rather than solves the difficulty. The problem, it is evi- 

 dent, was no hair-splitting ; it dealt with the very nature and 

 origin of being, and it agitated the minds of earnest men at a 

 time of fervid and widespread enthusiasm for knowledge. 



Now closely allied to the argument concerning universals was 

 that concerning "matter and form." Whether the terms used 

 were "form and matter," "force, energy or pneuma and 

 matter," "soul, archceus or life and body," "determinative 

 essence and determinate subsistence," "male principle and 

 female element," "the potter and the -clay of the potter"; 

 or whether again they were "effect and cause," "nature and 

 law," " being and becoming," the riddle lay in the contrast of 

 the 'static and dynamic aspects of things ; in the incessant forma- 

 tion of variable individuals in the eternal ocean of existence. 

 Even Francis Bacon never got out of the tangle of Form, 

 Cause and Law. It has been the temptation of philosophers 

 of all times, and even of Harvey himself, than whom none had 

 put better the conditions of scientific method, to suppose that 

 by means of abstraction kinds may be apprehended ; that thus 

 they may get nearer to the inmost core of things ; that by purg- 

 ing away the characters of individuals they may detect the 

 essence and the cause of individuation ; not perceiving that the 

 content of notions is indeed in inverse proportion to their 

 universality. We see this error continually to-day. For 

 instance, we may discuss the causes of typhoid fever, and 

 bewilder ourselves by forgetting that there is no such thing as 

 typhoid fever, and that the only causes of a general notion are 

 the psychological causes of its generation in the mind of the 

 thinker at the time ; that which is due to objective causes is 

 of course not the notion, but the particular case— a very different 

 affair. 



Before motionless stuff —before the problem of the " primum 

 mobile," even Harvey himself, when he had come to the end of 

 his admirable experiments and began to indulge in contempla- 

 tion, stood helpless. In his need for a motor for his machine he 

 was not able to divest himself of the language nor even of the 

 philosophy of his day. In his day he could not help regarding 

 rest and motion as different things, and motion as a 



NO. 16 1 7, VOL. 62] 



superadded quality. The motion he attributes, not to a 

 property of the heart, but of the blood— to its "innate 

 heat," which is as far as he could possibly have got. 

 But, by way of explanation, he adds that the innate heat 

 of the blood " is not fire, nor derived from fire " ; nor is 

 the blood occupied by a spirit, but is a spirit ; it is also "celes- 

 tial in nature, the soul, that which answers to the essence of the 

 stars ... is something analogous to heaven, the instrument of 

 heaven." In denying that a spirit descends and stows itself in 

 the blood or elsewhere, as an "extraneous inmate," he bravely 

 says : " I cannot discover this spirit with my senses, nor any 

 seat of it " ; and yet, in the treatise " De Generatione," he pro- 

 pounds a theory of the impregnation of the female, not by any 

 material from the male, but by the influence upon her of a 

 "general immaterial idea" ; which, even for his own time, was 

 very substantial realism. The riddle which oppressed the great 

 thinkers, from the Greeks to Lavoisier, was, then, the nature 

 of the " Bildungstrieb" — of the " impetum faciens." What 

 makes the ball to roll? Does heart move blood, or blood move 

 heart ? and, in either case, what bestows and perpetuates the 

 motion ? Telesius, the first of the brilliant band of natural 

 philosophers in Italy of the sixteenth and seventeenth centuries, 

 still sought this principle of nature in the " form " of the peri- 

 patetics. Gilbert regarded his magnetic force as "of the nature 

 of soul, surpassing the soul of man." Galileo, although willing 

 to conceive circular motion as perpetual, and even self-existent, 

 was unable thus to conceive rectilineal motion. All these 

 naturalists, including Harvey, and even Descartes, followed the 

 medioeval world and Aristotle in deriving the source of motion 

 directly from that of the spheres — from the quintessence (vid. 

 Arist. De Coelo ; and Met. xii.). Till Copernicus transfigured 

 the cosmos, and Galileo and Nevvton carried terrestrial physics 

 into the celestial worlds, the heavenly bodies were regarded as 

 animated beings, themselves active, and, by propa;ation from 

 sphere to sphere, animating all " sublunary " matter, wheels 

 within wheels, even to its innermost particles. 



Of the origin of energy we have not solved the riddle ; we 

 have given it up ; but instead of finding its sources without 

 we find them within. Harvey's contemporary, Francis Bacon, 

 sagaciously guessed that heat is an expansive motion of par- 

 ticles ; but he regarded heat and cold as two contrary principles. 

 Almost in the same generation the brilliant John Mayow per- 

 ceived a substance in the air "allied to saltpetre," which passed 

 in and out of the blood by the way of the lungs or placenta. So 

 innate heat gave way to phlogiston, and soon afterwards oxygen 

 and the conservation of energy turned out to be the "form" 

 "spirit," "essence," "primum mobile," "causa efficiens," 

 " potentiality," and the rest of them ; so by Lavoisier, a vast 

 pile of metaphysics was blown into the air. But to kill a strong 

 theory outright takes many a generation ; realism, shaken by 

 Abelard, and scotched by Hales and Ockham, not only survived 

 to mislead Harvey, but it stretches its withered hand over us 

 still — in the nursery, in the schoolroom, in the university, and 

 in the great arguments of life.^ 



As strong as realism was a third adversity — the pride of the 

 human mind. The asceticism derived from the East, disdainful 

 of carnal things, brought the dualism of matter and spirit into 

 monstrous eminence ; and in respect of medicine, in a few 

 generations it turned the cleanest people in the world into the 

 most filthy.- Almost to this day the mechanical arts, presum- 

 ably concerned with lower categories, have been regarded as 

 base ; and the crafts, even of the laboratory, as unworthy of 

 great souls. 



Anatomy had to labour also against both ecclesiastical and 

 popular antipathy ; chemistry and mechanics were gross pur- 

 suits unless endowed with the perilous distinction of alchemy and 

 sorcery. Unfortunately, this charge upon the dignity of man 

 was made heavier rather than lighter by Petrarch and the 

 humanists of the Renascence ; and in Oxford of the seventeenth 

 century we find that Boyle was bantered by his friends as one 

 "given up to base and mechanical pursuits." In a certain 

 important respect medicine suffered greatly from this prejudice. 

 It is obvious that, speaking generally, medicine would find its 

 most positive and direct control in those diseases and in those 



1 The readers of Nature know how effectively this mischievous 

 survival has been attacked recently by Prof. Perry, Mr. Heaviside and other 

 contributors. But evjn greater men, whose blows still resound through 

 the centuries, have attacked it in vain. 



- Those curious in such things will notice that the mediaivalisin^ clergy 

 of our own day have discarded in their persons that fair linen which m their 

 fathers was the emblem and example of cleanliness. 



