Scotoma of systematics, or Herschel’s headaches and Darwin’s metaphysics
On scotoma
In 1974, one of my favourite authors, Oliver Sacks, was climbing in a remote part of Norway. In an unfortunate accident Sacks severely injured the nerves and muscles of his left leg. During his recuperation period in the hospital his leg was without any sensation or movement for several weeks. This created the extremely uncomfortable feeling as if Sacks’ leg was no longer a real part of his body, merely an inconveniently attached lifeless prosthesis. Neurologists have a general term to describe such a phenomenon: scotoma. Scotoma “denotes a disconnection or hiatus in perception, essentially a gap in consciousness produced by a neurological lesion” (Sacks, 1995: 150).
Sacks writes that scotoma is literally unimaginable to those who have not
experienced it, and to attain some appreciation of this bizarre phenomenon he recommends those curious enough to read his book A leg to stand on, in which he relates his experience, while under spinal anaesthesia. I think there is a less intrusive way to get a superficial or visceral sense of scotoma by trying to sleep tonight on your back with your arms folded behind your head. Whenever I do this, I often wake up with either one or both my hands completely senseless and unable to move, perhaps due to a combination of restricted blood flow and constant pressure on the nerves of my lower arms. It may then take up to a minute or so to regain sensation and movement in my hands. I can only imagine what an extreme form of this must feel like for an entire leg over an extended period of time!
No matter the interest of the physical manifestation of scotoma, the specific purpose of Sacks’ (1995) insightful essay, however, was to point out that the concept of scotoma can be transplanted with surprising ease to the realm of culture, history, or science. In this context it refers to a loss of knowledge, a disappearance of insight, a deletion from memory. Sometimes certain facts or ideas enter into the written record or the communal consciousness of a discipline or culture, whereupon they simply fall off the radar.
Sacks noticed that this applied to his scotomal symptoms. His surgeon considered
his predicament to be unique. Sacks was puzzled by this assessment, and decided
to search the scientific literature to find out more about the symptoms he
was suffering from. Three years in the library resulted in nothing. It wasn’t
until Sacks bumped into a circular from 1864 by American neurologist Weir Mitchell that he found ample documentation of similar symptoms, mainly from victims of the American Civil War 1861–65. However, after a period of brief interest, Mitchell’s observations disappeared into the great dustbin of history, until World War I secured a rich stream of fresh cases for documentation. But again, history repeated itself, and the documentation was scotomized, only to re-emerge during World War II, when large numbers of injured people provided a rich substrate for documentation. Interestingly, these instances appear to have been genuinely independent, for no acknowledgments of previous work were recorded in the successive studies.
Sacks uncovered another interesting instance of disciplinary scotoma when he studied migraines in the mid-1960s. Himself suffering migraines since he was a little child, and starting work in a headache clinic, Sacks was drawn into an in-depth study of migraine. As a doctor charged with recording crisp diagnoses of the symptoms afflicting his patients, he was puzzled that often this seemed impossible. His patients would report perceiving complex geometrical
patterns during migraine attacks, symptoms that had apparently been left entirely unrecorded in the literature of the time. It wasn’t until Sacks hit upon an 1860 volume of the Victorian physician Edward Liveing in the rare book section of his college library that he found the first brief reference to the geometrical patterns reported by his patients.
His attention was especially attracted by a reference to a paper by the astronomer John Frederick Herschel who gave comprehensive descriptions of exactly the
symptoms described by Sacks’ patients. This paper was doubly remarkable because it was autobiographical. Herschel essentially described his own visual migraines. Sacks writes: “I felt I had struck paydirt at last.” For about a century between Herschel’s report and Sacks’ work in the headache clinic, no other reports of these particular migraine symptoms seemed to have been recorded, even though Sacks estimated that about five percent of his migraine patients experienced them occasionally. Consequently, this finding was one of the decisive triggers that motivated Sacks to cure this case of scotoma by recording the symptoms of his own patients and going off into a writing frenzy in which he composed the complete first draft of his book Migraine in a mere nine days!
A personal scotoma revealed I read this story several years ago, and it was certainly not on my mind
when I passed 19 New King Street in Bath a few weeks ago. I recently moved to the University of Bath to start work on a large integrative project to elucidate the phylogeny of crustaceans, and while I walked home after work, my head swimming with images of the creatures I had to collect and all the lab equipment that I needed to order, I suddenly noticed two plaques framing a white door on a house just a block from my home. One read “The William Herschel Museum,” while the other read “Here lived William Herschel A.D. 1781.” The name Herschel rang a faint bell. Somehow it reminded me of Charles Darwin, but I didn’t know why. As I started to trace the source of my indistinct memories, it became clear that I was about to discover the extent of a personal scotoma that I had incurred over several years. As I bared several layers of my intellectual scotoma a nice story about the connections between Charles Darwin and the Herschels started to take shape. It turned out that migraines were not John Herschel’s only headache, and identifying the other headache revealed a scotoma of truly momentous proportions.
On intellectual scotoma
Barring an unfailing photographic memory of unlimited capacity, it is inevitable to sustain intellectual scotoma. This explains why many of us can read a book for the second time with as much enjoyment as the first time, and why even
our own writings, which we consciously committed to paper at some time, may strike us as fresh insights when read several years later. One way to counteract the entropic force of time, that ineluctably reduces our memories to formless heaps, is to structure the information we take in as much as possible. It is easier to remember information when it consists of a cluster of bits of data that are logically connected to each other, than it is to remember a jumbled mess of unrelated bits. This is probably the reason why I couldn’t quite place the name Herschel, although it sounded familiar. It turned out that over the years I had encountered John F. Herschel a number of times while reading about the history of science. Especially biographical works are studded
with countless names, and unless they are immediately fastened by ties of logic to thematic anchors in the banks of memory, they will start a life as the tumbleweeds of the mind. For years John Frederick Herschel lacked a permanent memory address in my head. This essay has provided me with the framework to cement him more securely in my memory, which he certainly deserves.
The beginning of Herschel fame It turns out that I live practically next door to the very spot where in March 1781 William Herschel (1738–1822), father of John F. Herschel,
discovered the planet Uranus. William was born as Friedrich Wilhelm Herschel on 15th November 1738 in Hanover, Germany. From an early age on, a career in music seemed to be in the offing for little William. His father was a military musician, and William ended up playing in the same military orchestra. In 1757 William moved to England, where he earned his living by composing, playing, and teaching of music. However, in the early 1770s, William started to develop his interest in astronomy seriously. Reading books and buying his first telescope, William’s gaze was steadfastly upwards to the heavens, but he quickly became dissatisfied with the quality of his telescope. So in 1773 William resolved to build his own telescope. From then on, his telescope provided the first glimpses of our galaxy for many of Herschel’s music pupils and visitors. In 1772 William’s sister Caroline joined him in Bath, and William quickly trained her to become his right arm in his astronomical investigations. In a letter to Miss Maria Mitchell (the American astronomer who was the first woman to discover a comet, and after whom the Miss Mitchell’s comet was named), Caroline Herschel wrote that her brother had trained her as “an adept assistant willing to struggle long hours at his side as no hired, indentured, or enslaved help would do” (Sobel, 2005: 189). In the most self-effacing manner Caroline wrote “I am nothing, I have done nothing at all; all I am, all I know, I owe to my brother. I am the only tool which he has shaped to his use – a well-trained puppy-dog would have done as much” (see this link).
In view of Caroline’s more than slavish dedication to her brother’s pursuits, it is particularly ironic that on the night of 13th March 1781, when William Herschel discovered Uranus from the garden of his house in Bath, she was not by his side. Scarcely expecting to discover the first planet in modern times, William initially wondered whether he had perhaps discovered a new comet. It wasn’t until November 1781, after the Herschels were
“joined by I daresay half the astronomers in Europe, not to mention Russia – all fixated upon it” (Caroline in Sobel, 2005: 191) that it became clear that Herschel’s comet was in fact Uranus. Having discovered the planet furthest from the sun then known (it turned out that repeated observations of Uranus could be traced as far back as 1690, but it was always considered a star; Buttmann, 1970: 6), William was heralded an astronomical hero, and in November 1781, close to his 43rd birthday, William received the Copley Medal from the Royal Society. To facilitate further astronomical research, and to alleviate Herschel’s burden to make a daytime living as a music teacher, King George III awarded William an annual stipend of 200 pounds, and his sister Caroline 50 pounds for assisting him. This turned out to be money extremely well invested, because Herschel’s productivity and astronomical ingenuity have created a rich legacy of fundamental insights, from his discovery of the infrared part of the electromagnetic spectrum to the mapping of thousands of star clusters, and from the discovery of the roughly disk-shaped form of the Milky Way, to the directional movement of our solar system through the galaxy. At the end of his productive life, there was no one who had explored and expanded the limits of our understanding of the galaxy as much as had William Herschel.
The relationship between William Herschel and Charles Darwin: analogies When I learned about William Herschel’s life and work, I couldn’t
help but be struck by several parallels with the life and work of Charles Darwin. Both Darwin and Herschel were unique among contemporaries in expanding the boundaries of our understanding about the universe and life. Both men possessed extraordinary powers of observation, which allowed Herschel to construct a more detailed map of the universe than any predecessor had achieved, and which allowed Darwin to generate the necessary grist for his theoretical mill. Both gentlemen possessed an uncompromising work ethic fired by a burning ambition
to make a contribution to the natural sciences, and they adopted a tenacious single-mindedness to achieve their scientific goals. Both Darwin and Herschel saw their careers boosted, albeit in different ways due to differences with respect to financial safety and the amount of previously published scientific work, by receiving prestigious medals from the Royal Society in London in their early 40s. Herschel received his award for discovering Uranus, while Darwin was rewarded for his monographic work on living and fossil barnacles. Incidentally, at the time of their awards, Darwin and Herschel had both been working on their projects for about eight years. It was in 1845 when Darwin wrote to Hooker “I hope this next summer to finish my S. American geology,
then to get out a little zoology” (see my column in issue 54 of the Newsletter), and he was awarded the Royal Medal in 1853. Herschel first started to develop a serious active interest in astronomy in 1773, buying books, and parts to build his own telescope. He received his medal in 1781.
Naturally, these achievements of Darwin and Herschel are disparate in terms of their subject matter, but an underlying similarity is obvious as well. For both gentlemen, the medals awarded by the Royal Society were an acknowledgement of valuable scientific work, but compared to their later successes, this initial work, however valuable, seems to have a comparatively low “oomph-factor.” Although William Herschel’s name may be most tightly linked with his discovery of Uranus, his later work arguably did much more to expand our knowledge of the universe, both conceptually and empirically. Similarly, Darwin’s work on cirripedes only attained its full significance within the context of the evolutionary theory he elaborated and published afterwards. In fact, Darwin’s barnacle monograph can be considered the first ‘modern’ phylogenetic work ever published, although that may not be generally realized (Ghiselin, 1996, 1997a, b). The theoretical unification of biology afforded by the Origin earned Darwin his deserved status as “Newton of the grassblades” (Ghiselin, 1997a: 293), but his rich documentation of nature’s ways in his previous works, his barnacle monograph prominently among them, fully justifies labelling him biology’s Copernicus as well.
The relationship between John Herschel and Darwin: cause and effect The previous resemblances between the work of Charles Darwin and William
Herschel are, of course, analogies only. However, a much closer connection binds Darwin and William’s son John Herschel (1792–1871) (for biographical information on John Herschel see Buttmann, 1970 and King-Hele, 1992). In 1809, the year of Darwin’s birth, John enrolled at Cambridge University at age 17 to begin what would turn out to be an extraordinarily wide-ranging intellectual adventure that would continue to the end of his life. Perhaps not too surprising, considering his origins as a seed sown in
such a rich intellectual substrate, John turned out to be a prodigy. Intensely
aware that an active intellectual life depends crucially on the successful
preservation of time, the thin, tall, and restless John lived a life of almost
maniacal activity. John put himself on the scientific map in no uncertain terms by earning, at age 21, membership to the Royal Society of London for original work in mathematics. This was the start of a career that ranged widely across astronomy, chemistry, physics, mathematics, philosophy, and even including a short dabble in law, and several years as Master of the Mint (where his success, alas, was less apparent). Herschel’s obvious gifts for scientific work were balanced by his aspirations in art and poetry, and he was deeply committed to his family as well. His marriage with his 19 years younger wife is simply described as “a union of unclouded happiness” (Ring in King-Hele, 1992). His many accolades include no less than five medals from the Royal Society, a knighthood, presidency of the British Association, as well as the Royal Astronomical Society, and, finally, a resting place next to Newton in Westminster Abbey. In short, for his contemporaries Herschel was the epitome of a man of science.
John Herschel lived for several years in the mid-1830s in Cape Town, South
Africa, where he mostly committed himself to completing and extending his father’s astronomical observations of the heavens, securing his own reputation as a gifted astronomer in the process. It was at the Cape that he also took an interest in natural history. Keenly aware of their potential importance, Herschel sent a sample of trilobites that he received from a visitor, to Roderick ‘Sir Silurian’ Murchison, which provided the first evidence of the Silurian in Africa (Warner in King-Hele, 1992). Herschel had
a particular interest in the local flora, especially the bulbous plants, such as amaryllids and orchids, and he collected and grew up to 200 different species in his garden. He also carried out careful morphological and comparative studies
on the plants. According to Warner (in King-Hele, 1992) this instilled in John
“ideas on character associations and the logical basis of classification that were far in advance of their time; in some cases more than a century was to pass before similar systematic observations were made and interpreted. These ideas, put forward in a letter to Herschel’s friend Charles
Lyell written from Feldhausen in 1836, are entirely consistent with modern
ideas of cladistics and, further, were at least partly responsible for forming
Herschel’s belief at that time that the origination of species is a natural rather than a miraculous process.”
In May 1836 the Beagle landed at the Cape of Good Hope. Finally Darwin had the chance to meet John Herschel, an event that Darwin must have eagerly anticipated. In his last year in Cambridge, Darwin read two works that would influence his thinking beyond anything else. The first one was Alexander von Humboldt’s Personal narrative of travels to the equinoctial regions of the new continent during the years 1799–1804. It is hard to exaggerate how much this work stoked Darwin’s enthusiasm to become a naturalist explorer. Richards (2002) even goes so far as to label Darwin effectively a German Romantic himself, based on what he perceives as the deep penetration of Humboldt’s Romantic view of nature into Darwin’s thinking about matter and mind. The second work that, less controversially, shaped Darwin’s thinking throughout his life was John Herschel’s Preliminary discourse on the study of natural philosophy, from 1830. Darwin wrote that the reading of these works
“stirred up in me a burning zeal to add even the most humble contribution to the noble structure of Natural Science. No one or a dozen other books influenced me nearly so much as these two” (Darwin, 1995: 23).
Herschel’s book set out a methodology of science, which as argued by Hull (1973), and more specifically by Gildenhuys (2004), Darwin applied throughout his own investigations. In this way Darwin tried to solve the “mystery of mysteries,” the famous phrase coined by John Herschel for the seemingly irresolvable problem of origin of organismic diversity. Since Darwin closely followed the methodological precepts laid down by Herschel to answer what Herschel himself saw as the most portentous question in natural science, one would perhaps be excused to think that Herschel would be utterly delighted with the publication of the Origin. What nobler monument to Herschel’s scientific philosophy than to show its power to resolve the mystery of mysteries?
Herschel’s second headache Darwin included Herschel in a list of 80 or so scientists and philosophers who had the privilege to receive a presentation copy of the Origin that came accompanied by a nice letter. After all, what better way to ease the reception of his most important brainchild? In the opening paragraph of the Origin Darwin was explicit enough about his debt to Herschel:“
When on board H.M.S. Beagle, as naturalist, I was much struck with certain facts in the distribution of the inhabitants of South America, and in the geological relations of the present to the past inhabitants of that continent. These facts seemed to me to throw some light on the origin of species – that mystery of mysteries, as it has been called by one of our greatest philosophers.”
Unfortunately, Herschel’s response was not at all what Darwin had hoped for. In a letter to Charles Lyell, Darwin wrote: “I have heard, by a roundabout channel, that Herschel says my book ‘is the law of higgledy-piggledy.’ What this exactly means I do not know, but it is evidently very contemptuous. If this is true this is a great blow and discouragement” (in Darwin, 1995: 220).
It was true, and it must have been a great disappointment. Darwin had created
a huge headache for Herschel, because the core and most radical aspect of Darwin’s new conception of nature clashed head-on with the fundamental foundation of Herschel’s own outlook on life. The most radical aspect of Darwin’s view of life was, of course, his uncompromising philosophical materialism. The reception of his unwavering commitment to materialism had worried Darwin from the very beginning of his theorizing. For example, in his ‘M’ notebook, which contained metaphysical musings, Darwin
wrote: “To avoid stating how far, I believe, in Materialism, say only that emotions, instincts degrees of talent, which are hereditary are so because brain of child resemble, parent stock” (in Bowler, 1990: 85). Darwin evidently felt it was necessary to nuance his opinion that even aspects of the human mind are simply materially transmitted between generations.
It was exactly Darwin’s bringing of ‘mind’ within the purview of ‘matter’ that was in deep conflict with traditional notions accepted by many of his contemporaries. It would perhaps not be accurate to say that Darwin ‘reduced’ mind to mere matter, but he did specify a deterministic relationship between, for example, the abstract realm of ideas and the concrete realm of the brain (see Richards, 2005). By drawing attention to the distinction between the merely abstract and the concrete, and questioning the independent existence of the former, Darwin constructed “a single theoretical system, and one that has a unitary metaphysical basis” (Ghiselin, 2000: 270). Rather than maintaining the age-old dichotomy between spirit and matter “Darwin moved concrete particular things to the center of the metaphysical world” (Ghiselin, 2005: 127). It was this metaphysical revolution in thought that was entirely unacceptable to Herschel, and which invited his labelling of Darwin’s view of nature and evolution as “the law of higgledy-piggledy.” As argued by Hull (1973), Herschel believed that natural laws instituted by God governed nature. Even if the reality of evolution could be accepted, Herschel could not accept that the direction of change was independent from a higher intelligence, and from a guiding purpose.
The most fundamental modern objections to the Darwinian worldview are still cast in the same mould, by denying materialism or the concrete as the only reality. For example, in a recent article in the journal Zygon, which is dedicated
to the exploration of the relationship between science and religion, Haught
(2005: 365) writes of the “conflation of biology with materialism.” Similarly, in an attempt to justify the scientific respectability of intelligent design arguments in biology, Meyer (2002) denies that materialism has a metaphysically privileged position (see my essay in issue 57 of this Newsletter for further discussion of Meyer’s ideas). These authors would posit the existence of an independent realm of the abstract, entirely divorced from the material world, the concrete. In contrast, most modern scientists are entirely committed to materialism as the only metaphysical reality. At least, that was an expectation I had, until recently.
Scotoma in systematics It wasn’t until I carefully studied the work of Michael Ghiselin
over the last year that I realized that the Darwinian revolution is still in full swing. It was a very revealing experience to discover the boundaries of my own ignorance about the profound metaphysical implications of the Darwinian view of life. I recently gave a talk at a conference at the Muséum National d’Histoire Naturelle in Paris, and there I presented the audience with three simple statements designed to provide a quick estimate of a person’s metaphysical leanings: (1) I’m a member of the species Homo sapiens, (2) A type specimen of a species is generally a good example of that species, and (3) One of the defining features of Mammalia is hair.
The results of this little polling were very revealing. The vast majority of audience members fully agreed with the above statements. I did too, about ten months ago, until I studied Ghiselin’s masterful Metaphysics and the origin of species (1997a). For me personally, reading this book was by far the most important step in my intellectual development for years. The basic premise and its key insight are deceptively easy to state. The premise: everything in the universe can be labelled as either a ‘class’ or as an ‘individual.’ The latter are without exception concrete.
The insight: species and other taxa are individuals.
The implications of accepting or rejecting this premise and its key insight go right to the heart of the metaphysics of Darwinism. It represents the most fundamental decision any natural scientist can make in his or her career. Yet, surprisingly few of us seem actually to wrestle explicitly with this issue. The big question is why? How can it possibly be that this most fundamental
aspect of Darwin’s revolution in thought has either been forgotten, or has not yet been internalised by many workers? It wasn’t very surprising that Herschel’s migraine headaches were erased from memory. After all, as pointed out by Sacks (1995), Herschel’s observations were considered to fall within the domain of medicine, one of the very few domains where Herschel’s insights were not accepted as those of an insider. However, the metaphysical implications of the worldview of Herschel’s most famous philosophical disciple caused him a headache of much larger proportions. Yet, a full awareness of the implications of the same Darwinian metaphysics is conspicuously lacking from the conceptual toolkit of many modern workers. In the next issue I will attempt to explain this surprising situation, and what it means to embrace fully the Darwinian view of life, metaphysics and all.
References
Bowler, P. J. 1990. Charles Darwin. The man and his influence. Cambridge University Press, Cambridge.
Buttmann, G. 1970. The shadow of the telescope. A biography of John Herschel. Lutterworth Press, Guilford & London.
Darwin, C. 1985. On the origin of species. Penguin Books, London.
Darwin, F. 1995. The life of Charles Darwin. Senate, London.
Ghiselin, M. T. 1996. Charles Darwin, Fritz Müller, Anton Dohrn, and the origin of evolutionary physiological anatomy. Mem. Soc. Ital. Scí. Nat. Mus. Civ. Stor. Nat. Milano 27: 49–58.
Ghiselin, M. T. 1997a. Metaphysics and the origin of species. State University of New York Press, New York.
Ghiselin, M. T. 1997b. Phylogenetics: a science no longer ignored. Hist. Phil.
Life Sci. 19: 279–284.
Ghiselin, M. T. 2000. The assimilation of Darwinism in systematic biology. In: Giovanni Canestrini: zoologist and Darwinist (Minelli, A., Casellato, S., eds.), pp. 265–281. Inst. Veneto Sci. Lett. ed Arti, Venice.
Ghiselin, M. T. 2005. The Darwinian revolution as viewed by a philosophical biologist. J. Hist. Biol. 38: 123–136.Gildenhuys, P. 2004. Darwin, Herschel, and the role of analogy in Darwin’s origin. Stud. Hist. Phil. Biol. & Biomed. Sci. 35: 593–611.
Haught, J. F. 2005. Science and scientism: the importance of a distinction. Zygon 40: 363–368.
Hull, D. L. 1973. Darwin and his critics. The reception of Darwin’s theory of evolution by the scientific community. Harvard University Press, Cambridge.
King-Hele, D. G. 1992. John Herschel 1792–1871: a bicentennial commemoration. The Royal Society, London.
Meyer, S. C. 2002. The scientific status of intelligent design: the methodological equivalence of naturalistic and non-naturalistic origins theories. In: Science and evidence of design in the universe. Ignatius Press.
Richards, R. J. 2002. The romantic conception of life. Science and philosophy in the age of Goethe. The University of Chicago Press, Chicago.
Richards, R. J. 2005. Darwin’s metaphysics of mind. In: Darwin and Philosophy, Hoesle, V., Illies, C. (eds.), pp. 166–180. Notre Dame University Press, Notre Dame.
Sacks, O. 1995. Scotoma: forgetting and neglect in science. In: Hidden histories of science. A New York Review Book, New York.
Sobel, D. 2005. The planets. Fourth Estate, London.
Ronald Jenner Department of Biology and Biochemistry, University of Bath, Bath, BA2
7AY, UK.
Created by Mark D Sutton on the 2006-02-23. (Version 2.0)