Part 5

Boyle seems to have acquired most of his medical knowledge between, say, 1649 and 1662. It is worth recalling some of the trends and conflicts that formed the medical environment during this period. Among the major trends, first place, perhaps, must be given to Galenic doctrine, which had come under progressively severe attack. Molière, who lived from 1622 to 1673, showed in his comedies the popular reaction to a system which, although dominant, was clearly crumbling. The cracks in the edifice even the layman could readily see. Nevertheless, Galenism had its strong supporters. Riverius, who lived from 1589 to 1655, was a staunch Galenist. An edition of his basic and clinical works was translated into English in 1657, and Latin editions continued to be published well into the eighteenth century.

Galenism, of course, had to withstand the great new discoveries in anatomy and physiology made by Vesalius, Aselli, Sanctonius, Harvey, and others, not to mention the host of great investigators who were more strictly contemporaries of Boyle.

Galenism also faced the rivalry of chemistry. The so-called "antimony war" in the earlier part of the century marked an important assault on Galenism, and the letters of the arch-conservative Guy Patin (who died in 1672) help us appreciate this period. However, even more important was the work of van Helmont, who developed and extended the doctrines of Paracelsus and represented a major force in seventeenth-century thought. Boyle was well acquainted with the writings of van Helmont, who, although his works fell into disrepute as the mechanical philosophy gradually took over, nevertheless in the middle of the seventeenth century was a highly significant figure. In 1662 there appeared the English translation of his Oriatrike, while Latin editions continued to be published later in the century.

In this connection I might also mention the subject of "natural magic," which had considerable significance for medicine. The best-known name is, perhaps, Giovanni Battista della Porta (1545-1615), whose books continued to be published, in Latin and English, during this period when Boyle was achieving maturity.

Profound developments, of course, arose from the new mechanics and physics and their metaphysical background, for which I need only mention the names of Descartes, who died in 1650, and Gassendi, who died in 1655. And then there was also the new methodological approach, that critical empiricism whose most vocal exponent was Francis Bacon, which led directly to the founding of the Royal Society in 1660 and its subsequent incorporation. These phases of seventeenth-century thought and activity I do not intend to take up.

In this turbulent riptide of intellectual currents, Robert Boyle, without formal medical education, performed many medical functions, as a sometime practitioner, consultant, and researcher. Repeatedly he speaks of the patients whom he treated, and repeatedly he refers to practitioners who consulted him, or to whom he gave advice. In addition, through his interest in chemistry, he became an important experimental as well as clinical pharmacologist, and his researches in physiology indicate great stature in this field. If we were to draw a present-day comparison, we might point to investigators who had both the M.D. and the Ph.D. degrees, who had both clinical and laboratory training, and who practiced medicine partly in the clinical wards, partly in the experimental laboratories. Boyle, of course, did not have either degree, but he did have a status as the leading virtuoso of his day.

The virtuoso has been the subject of a most extensive literature. He aroused considerable contemporary hostility and satire and his overall significance for medical science is probably slight, with a few striking exceptions. Robert Boyle is one of the great exceptions.

First of all, the virtuoso was an amateur. In the literal sense the amateur loves the activities in which he engages, and in the figurative sense he remains independent of any Establishment. Not trained in any rigorous, prescribed discipline, he was not committed to any set doctrine. Furthermore, he was not restricted by the regulations which all Establishments employed to preserve their status, block opposition, and prevent competition. In many fields the Establishment took the form of a guild organization--in medicine, the Royal College of Physicians.

Boyle was a wealthy and highly talented man who could pursue his own bent without needing to make concessions merely to earn a living. He remained quite independent of the cares which oppressed those less well endowed in worldly goods or native talent. Sometimes, of course, necessity can impose a discipline and rigor which ultimately may serve as a disguised benefit, but in the seventeenth century, when Boyle was active, the lack of systematic training and rigorous background seemed actually an advantage. Clinical chemistry and the broad areas which we can call experimental medicine had no tradition. Work in clinical chemistry, clinical pharmacology, and experimental physiology was essentially innovation. And since innovations are often made by those who are outside the Establishment and not bound by tradition, we need feel no surprise that the experimental approach could make great progress under the aegis of amateurs. Necessarily the work was rather unsystematic and undisciplined, but system and discipline could arise only when the new approach had already achieved some measure of success. Through the casual approach of amateurs this necessary foundation could be built.

Boyle, as a clinician, remained on excellent terms with medical practitioners. For one thing, he took great care not to compete with them. As stated, he "was careful to decline the occasions of entrenching upon their profession." Physicians would consult him freely. As a chemist and experimental pharmacologist, he prepared various remedies. Some of these he tried out on patients himself, others he gave to practitioners who might use them. Boyle seems to have abundantly provided what we today call "curbstone consultations."

In no way bound by guild rules and conventions or by rigid educational standards, Boyle was free to learn from whatever sources appealed to him. Repeatedly he emphasized the importance of learning from experience, both his own and that of others, and by "others" he included not only physicians and learned gentlemen, but even the meanest of society, provided they had experience in treating disease. This experience need not be restricted to treatment of humans but should include animals as well. Thus, in speaking of even the "skilfullest physicians," he indicated that many of them "might, without disparagement to their profession, do it an useful piece of service, if they would be pleased to collect and digest all the approved experiments and practices of the farriers, graziers, butchers, and the like, which the ancients did not despise...; and ... which might serve to illustrate the methodus medendi." He was quite critical of physicians who were too conservative even to examine the claims of the nonprofessionals, especially those who were relatively low in the social or intellectual scale. This casts an interesting sidelight on the snobbishness of the medical profession.

Boyle's willingness and ability to ignore the restrictions of an Establishment represent the full flowering of what I might call the Renaissance spirit--the drive to go outside accepted bounds, to explore, to try, to avoid commitment, and to investigate for oneself.

What internal and external factors permit a successful breakaway from tradition? Rebels there have always been, yet successful rebels are relatively infrequent. The late seventeenth century was a period of successful rebellion, and the virtuosi were one of the factors which contributed to the success. Robert Boyle played a significant part in introducing new methods into science and new science into medicine.

We must realize that Boyle was primarily a chemist and not a biologist. He thought in chemical terms, drawing his examples from physics and chemistry; he did not think in terms of the living creature or the organism, and as a mechanist he passed quite lightly over the concept or organismic behavior. His basic anti-Aristotelianism prevented his appreciating the biologically oriented thought of Aristotle. Instead, Boyle talked about the inorganic world, of water, of metals and elements, of physical properties. He ignored that inner drive which Spinoza called the conatus; or the seeds of Paracelsus or van Helmont; or the persistence over a time course of any "essence" or "form." Since he dealt with phenomena relatively simple when compared with living phenomena, he could, for this very reason, make progress, up to a point. As a chemist, he could seek fairly specific and precise correlations of various concrete environmental factors, and then assume that living beings behaved as did the inorganic objects which he investigated. However, he always excepted the soul of man, as outside his investigations.

But while Boyle was a skillful chemist, judged by the standards of his time, we cannot call him a skillful medical investigator. This represents, however, the fault of the era in which he lived rather than any fault peculiar to him. Boyle's medical studies fall into at least two categories. These were the purely physiological experiments, such as those on respiration or on blood, and the more clinical experiments, concerned with pharmaceuticals, clinical pharmacology, and clinical medicine. The purely physiological experiments have great merit and were profoundly influential in shaping modern physiology. The clinical experiments throw great light on the development of critical judgment in medical history, and the relations of judgment and faith.

In 1775, John Hunter wrote a letter to Jenner that has become quite famous. Hunter had just thanked Jenner for an "experiment on the hedgehog." But, continued Hunter, "Why do you ask me a question by way of solving it? I think your solution is just, but why think? Why not try the experiment?" The word "just," of course, in its eighteenth-century sense, means exact or proper, precise or correct. A "just solution" is one that is logically correct. The "think" refers to Hunter's own uncertainty. He is not content with a verbal or logical solution to a problem, he wants empirical demonstration. Why, he is asking, should we be content with merely a logically correct solution when we can have an experiential demonstration. Try the experiment. Put the logical inference to the test of experience.

This empirical attitude, not at all infrequent in the latter eighteenth-century medicine, was quite unusual in the seventeenth-century medicine. This was precisely the attitude that Robert Boyle exhibited in his clinical contacts.

Medicine, at least textbook medicine, was rationalistic. Textbooks started with definitions and assertions regarding the fundamentals of health. This we see particularly in a Galenic writer such as Riverius. Medicine, he said, "stands upon the basis of its own principles, axioms and demonstrations, repeated by the demonstration of nature." In his text, Riverius first expounded a groundwork concerning the elements, temperaments and humors, spirits and innate heat, the faculties and functions; then the nature of the diseases which resulted from disturbances of these; and finally the signs of disease and the treatment that was appropriate. All were beautifully interdigitated in a logical fashion, and for any recommended therapy a good reason could be found. There was, however, a serious difficulty. If anyone were so bold as to ask, But how do you know? only a rather lame answer would come forth. The exposition rested in large part on authority or else largely on reasoning from accepted premises--a "just" reasoning. And while much keen observation was duly recorded and a considerable mass of fact underlay the theoretical superstructure, the idea of empirical proof was not current. Riverius chopped logic vigorously and drew conclusions from unsupported assertions in a way that strikes us as reckless.

For a body of knowledge to be a science, it must indicate a logical connection between first principles, which were "universal," and the particular case. The well-educated physician could always give a logical reason for what he did. The empiric, however, was one who carried out his remedies or procedures without being able to tell why. That is, he could not trace out the logical connection between first principles and the particular case.

Galenism suffered especially from logical systematization, and the system of van Helmont, while far less orderly, also had its own basic principles on which all else depended. Boyle, however, practiced medicine on a thoroughly different basis. He did not depend on system or logic. In the words that Hunter used to Jenner over a hundred years later, other physicians would think the answers to their problems. Boyle, however, preferred to try the experiment. He wanted facts.

But this attitude, which sounds so modern, so praiseworthy and enlightened, had one serious flaw. What was a fact? And how did you know? This important problem, so significant for the growth of scientific medicine, we can study quite readily in the works of Robert Boyle.

The problem, in a sense, resolves around the notion of credulity. What shall we believe? Boyle makes some distinctions between what he has seen with his own eyes and what other people report to have seen. Thus, he mentions "a very experienced and sober gentleman, who is much talked of" who cured cancer of the female breast "by the outward application of an indolent powder, some of which he also gave me." But, he adds cautiously, he has not yet "had the opportunity to make trial of it." Clearly, since he cannot make the trial himself, Boyle withholds judgment, even though the material came from a "very experienced" gentleman. Or again, he talks about "sober travelers" who made certain claims regarding the treatment of poisons. But, he says, "having not yet made any trial of this my self, I dare not build upon it."

There are numerous such instances, scattered throughout his works, where he reports an alleged cure but specifically indicates his own mental reservations. Clearly, he is quite cautious in accepting the statements of others, even though they were "sober" or "experienced" or even "judicious." On the other hand, he is extremely uncritical when he himself uses the term "cure" and when he attributes cures to particular medicines.

His skepticism he indicates in references, for example, to Paracelsus and van Helmont. Their specific remedy against "the stone," he says, and their claims that they can reduce stones to "insipid water, is so strange (not to say incredible) that their followers must pardon me, if I be not forward to believe such unlikely things, til sufficient experience hath convinced me of their truth." Here, of course, we see further a feature of critical acumen. A claim is made, but if this claim runs counter to Boyle's own accepted body of knowledge, or to logical doctrines derived from other directions, mere assertion cannot carry conviction. "Sufficient experience" must play its part, and just what constitutes "sufficient" we are not quite sure.

In judging the effectiveness of a remedy or the credibility of a statement, one of the most important weapons was analogy. Direct observation of a phenomenon was good. Next best was direct observation of some analogous phenomenon whereby one body acted upon another to alter its properties or induce significant changes. Boyle drew his analogies largely from chemistry, but he had no hesitation in applying them to medicine.

Claims that medicines swallowed by mouth could dissolve stones in the bladder seemed a priori unlikely. Yet there was considerable authority that this took place; many persons had reported that this was a fact. Boyle kept an open mind. He might be highly skeptical in regard to the claims for any particular medication, but he did not deny the principle involved. The possibility that some fluid, when swallowed, could have a particular specific action on stones in the bladder, without affecting the rest of the body, he considered quite plausible through the analogy that quicksilver has an affinity with gold but has no effect upon iron. Furthermore, a substance than can corrode a solid body may nevertheless be unable to "fret" a different body which is considerably softer and thinner, if the "texture" does not admit the small particles. Reasoning by analogy served to explain the logical plausibility. In other words, he was very open-minded. He refused to dismiss all such claims, and provided analogy as a reason for keeping his mind open; yet he refused to accept particular claims of medicine that dissolved stones, because the evidence was not convincing. We could scarcely ask for more.

An important seventeenth-century medical document was the report of Sir Kenelm Digby, regarding the so-called "weapon salve." The essay describing this famous powder was written in 1657, and I have discussed it at some length elsewhere. Here again Boyle keeps an open mind, saying, "and if there be any truth in what hath been affirmed to me by several eye-witnesses, as well physicians as others, concerning the weapon-salve, and powder of sympathy, we may well conclude, that nature may perform divers cures, for which the help of chirurgery is wont to be implored, with much less pain to the patient, than the chirurgeon is wont to put him to."

One great advantage of chemistry, thought Boyle, lay in the help it provided in investigating the materia medica. Chemistry, he thought, could help to purify many of the inorganic medicines and make them safer, without impairing their medicinal properties. Furthermore, chemistry could help investigate various medications customarily employed in medicine, where "there hath not yet been sufficient proof given of their having any medical virtues at all." Boyle believed that by proper chemical analysis he could isolate active components, or, contrariwise, by failing to extract any valuable component, he could eliminate that medicine from use. While a major interest, perhaps, was a desire to provide inexpensive medicines, he was well aware that much of what went into prescriptions probably had no value. Furthermore, he felt that his chemical analysis could indicate whether value and merit were present or not.