28. Degeneration 1882-1890

Charles Darwin was buried in Westminster Abbey on April 26th 1882 And though he was very much a man finding his way in the fledgling middle class, Ray Lankester didn’t know where to look, even then. Not for the first time Lankester was thinking of his own future, reacting to the impact of Darwin’s life and fearful of where some of the ideas might lead. He was suddenly aware that he was living through the final throes of a passing age. Eight years earlier he had been appointed Jodrell Professor of Zoology at University College and was well-known as a star performer in the lecture theatre and as a precise observer of marine invertebrates. That year he was 35 years old and he was adding a lot of weight to his already large frame and round, flat face.

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Lankester also spent a lot of time thinking about how people were struggling with their different social circumstances at the end of the nineteenth century. Not only were they living through the mature stages of the industrial revolution, but also through the associated scientific and technological ones. He agreed with Darwin that soon it would be the turn of biology to have some impact on daily life styles, perhaps through some control of breeding or by adapting to psychological stresses. But if there really was going to be a successor to Darwin these applications had better come soon and it was hard for him to spot a likely candidate in that congregation. He looked at the rows of scientists in the nave for possible contenders: Hooker and Huxley were the obvious ones but they and all the others he could see were too old.

Could biologists ever breed new crops and healthier humans, with the same basic mechanisms involving genes and sexual recombination? Lankester was the first to speak of what happened in the early moments of a new embryo, the changes inside the cells that were starting to be discovered. He was well-aware of the similarities between the application of Darwin’s ideas to social progress and what his friend Karl Marx had in mind at that time for political change. In 1879 Lankester had lectured on what was known of this to the Sheffield meeting of the British Association for the Advancement of Science. Marx had also been interested in the idea that societies might degenerate, and argued that if a new embryo has to struggle with a new environment, then some new kind of society would have to do the same.

Lankester was positive about these links and spoke optimistically of what came from such natural interactions long ago, fossilised hallmarks and other remains of geological processes. It was there in the rocks, old sediments, reworked by erosion of old surfaces, formed at the bottom of shallow seas, forced by earthquakes into the bowels of the earth to be heated and pressurised into another form, a harder metamorphic rock. These same layers of ancient environments also preserved similar species of Lankester’s beloved marine animals, closely related but different as a result of the constant changes of the self-organised living systems from those different ages.

As though to confirm these expectations, the religious controversy that had so dominated the last two decades of Darwin’s life began to die down after his death, only to be replaced by these more political ones. Huxley still fought some remaining dissenters of the new attitude, especially laymen’s views of miracles. Gladstone and the Duke of Argyll were well-known antagonists but most scientists regarded the arguments as old hat and they soon stopped.

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That also meant that fewer articles about evolution got published in the papers and the topic had an air of yesterday’s news. For some intellectuals there was the prospect that the two greatest ideas of the last half of the nineteenth century, Darwin’s natural selection and Marx’s materialism, were united in hopes for a scientific utopia. But war about threats from dictatorships and religious revivals soon eclipsed these ambitions.

Ray Lankester was sharp and critical both socially and professionally. He had been admired for his attention to detail by Darwin himself when the two had exchanged letters about earthworms and other species. The introduction to the great biologist came from Ray’s teacher Thomas Huxley whose lectures at the Royal College of Science, now part of Imperial College, were inspiring many men of the next generation. And because he lived in one of the streets in St James, it was easy to call in to the Geological Society and the Linnean to hear lectures on his way home from school.

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With this background his own destiny was clear and the 27 year old biologist became Professor of Zoology at University College London in 1874. He was one of the growingly successful English middle class, without a fortune let alone land but his educated drive more than made up for that. He rented rooms on the ground floor of a house by Hyde Park and he shared a housekeeper with one of the other tenants. He travelled regularly to Oxford, Plymouth, Naples and places in France and Germany. On the other hand, such a life style became very lonely and made it harder to value people outside one particular circle, and it encouraged arrogance.

A year later he was at a ceremony to mark the founding of the Marine Biological Association, soon to have its own headquarters at Plymouth. It was modelled on the Stazione Zoologica in Naples where Lankester had worked in the early 1870s when his Fellowship at Exeter College allowed him to spend much of his time in Italy.

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Then, as now, young scientists usually spent several years at the beginning of their career working hard at a substantial project. As well as experience and knowledge it built confidence and showed the world what the individual could do. Nowadays, this apprenticeship involves registering as a PhD student, but then you tended just to get on with it. Lankester special interest was in marine invertebrates, molluscs especially, and they grew in the Mediterranean, offshore Naples, where they could be collected in great profusion. He worked on Amphioxus, cuttlefish, several exotic worms and the electric eel was a special fascination. Darwin wrote to encourage him: “What ground work you did at Naples! I can clearly see that you will some day become our first star in Natural History.”th-11

The following year Lankester was in Naples again, pleased for the rare chance to be host to his mentor Thomas Huxley and show him the tanks of fish and other marine animals as well as some of the historical sites around the bay. But the eager young man became seriously ill with typhoid fever, common enough then for vulnerable Englishmen, and he took to his bed for several weeks. It meant that he missed another rare opportunity to see the eruption of Mount Vesuvius. All he could do was listen to the deep humming sound, though even inside his room the darkness and dust got everywhere.

In 1874 the Naples Station attracted two of Lankester’s young students from University College who had begun a collaborative project, Walter Weldon, a zoologist, and Karl Pearson, a mathematician. They were in Naples to make measurements of eleven different organs from hundreds of specimens of the shore crab. All the result distributed normally except one, the frontal breadth of the carapaces, and this became a distinguishing feature of different races of Carcinus moenas. Weldon ended their joint article: “It cannot be too strongly urged that the problem of animal evolution is essentially a statistical one.” Lankester was furious. It was another early sign of the new divide in understanding evolution: the qualitative and the quantitative. It was apparent between Lankester and Galton with their very different personalities. Although they both cultivated the image of an arrogant Victorian gentleman, the one was spontaneous and worked with feelings, while the other was calculating and difficult.

Everyone involved expected that observations from the more temperate oceans around the British Isles would prevail at the new Plymouth Marine Station, and the new building became operational in 1888. Equipped with boats and a stone building on the Citadel overlooking the naval dockyard, the young scientists had high hopes of finding more support for natural selection in the largely un-described marine realm. But to start with, work at the new laboratory gave evidence to support those who Lankester labelled the opposition. It was typical of many set-backs to promoting Darwin’s work at around that time and confirmed that the enthusiasm for natural selection did not lead to the conclusion that he was right.

Lankester thought that another set of confusing results came from observations of the pigmentation of the two surfaces of the flat-fish, whether it was right to assume that the pigmentation on the upper surface was inherited, or the result of light reacting from above or darkness from below. He was unhappy with a popular belief that science was to settle differences of this sort rather than to have both options. Comparisons between the young forms and the adults showed that prolonged exposure to light did stimulate pigmentation, and some patterns were inherited for sure. Like so many of the early experiments in biology these were observations in controlled conditions looking at either/or situations. Others expected it to be either pigmented or not, a star pattern or an arrowed one, light or dark, Darwin or Lamarck. Often, everyone was able to take away some argument for victory, and always there was some chance of ambiguity, uncertainty and need for more work. Of course we know now that the problems being considered were caused by physiological and developmental processes which involved many biochemical pathways. Then it was not at all clear on these issues and Lankester began to understand why Darwin couldn’t be proved right overnight. Without clear evidence all the options had to be left open, even if they were going to lead to frightening political difficulties.

Darwin’s ideas were declining in popularity through these years due to the continuing lack of any new evidence. Many cast around for some breakthrough in the many alternative explanations of life, all of which were dead-ends and false alerts. Try as he would, Lankester became more frustrated with his own failures to find useful clues in his classical observations of new species and he lost his temper with others who were equally unsuccessful looking elsewhere. But he was still determined to follow Darwin and Huxley with some faithful support and there were still plenty of places to seek it out. He was beginning to concentrate on the new studies in embryology and there were so many other new developments and disciplines in biology that helped him remain optimistic.

Just across the North Sea in Germany there was another way of seeing nature that looked back into The Enlightenment. The English liked to have a sense of purpose, an aim, something tangible, an object to strive for; on the other hand, many Germans saw life on earth as some vast transcendental process that changed under its own force. The generation of the 1870s which comprised men like Huxley and Norman Lockyer, the founding editor of Nature, believed from Goethe’s naturphilosophie that man and nature form a unity which can be studied and understood by the application of science.

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All these men, and of course Ray Lankester as well, believed with Faust that nature and moral ideals intermingle within each individual: “I only really enjoy my life when I win it every day afresh”. Only then did passion become set against passion, the anger of one side was set against the scorn of the other and a glorious victor moved forward amidst the tragedy of the other. But these interactions all happened together at different places and at different levels and intensities. Like Faust, Lankester searched for the mysterious power which bound nature into the whole; they believed this was the right path, and though they often went astray, they always returned to it. This was their deep faith.

Whenever he was in Germany Lankester liked to visit the leading biologist there, Ernst Haeckel (1834-1919), Charles Darwin’s fervent young supporter who visited him in 1866. He was also inspired by Goethe’s way of looking at biology, and the two had allowed him to think of a particular process in embryology which they called recapitulation. They had noticed that a growing embryo passed through stages corresponding to the sequence of adult forms in its species’ evolutionary history. Lankester had been interested in these apparently similar processes from his student days. th-9      th-1

Lankester explained why he and others of his times were so excited about the stages of early development in the embryo. They saw some connections in the embryos of lizards, birds and elephants which appeared to bear little resemblance to one another as adults. Although the youngest embryos in a related group usually look different, they then grow to look very similar, then become different again. In this hourglass shape, the middle waist was when the body plan was laid down, a time of minimal anatomical divergence. No wonder these late Victorian biologists thought there was some relationship between the way an embryo developed and the way it evolved, that ontogeny followed the same path as phylogeny.

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Meanwhile, back at University College in London at the end of the 1870s, Lankester’s alternative ideas of degeneration became more sophisticated, especially following the discussions he had had in Italy and Germany with his friend there Carl Dohrn (1806-1892) whose 1875 book gave Lankester more support for his own observations of embryo development. He began to formulate his own version of how degeneration might account for some evolutionary changes. After Darwin’s death these thoughts were set against growing support for environment-influenced along straight Lamarckian pathways.

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Degeneration: a chapter in Darwinism was the title both of Lankester’s Presidential Address to the Zoology Section of the British Association for the Advancement of Science at Sheffield in 1879 and of a short book, based on that lecture, which he published afterwards. Heavily based on Haeckel’s ideas of recapitulation, it differed in avoiding a linear pathway of evolution. Lankester gave lots of examples of species with unused organs, domestic ducks with smaller wings, blind cave animals and even rare families of humans with extraordinary musical talents. Not only did he risk being labelled a Lamarckian but the very mention of humans brought him face to face with political groups accusing him of destroying the structure of society with pornography and other decadent threats.

Could humans degenerate to a simpler form of society? Evolution was normally seen to turn the primitive into the advanced and civilised. Alternatively, instead of seeing evolution as progress Lankester was arguing the opposite. Could it sometimes return to the form of an earlier generation? Could this even explain different racial and even specific characters? Instead of representing progress and reform maybe evolution could also represent regression and decline. Quickly, this idea caught on with others who saw it as a possible explanation of the new tendencies in the arts, Dandyism, naturalism and mysticism.

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Others had it explain how some races had evolved less far than European ones while others had developed into decadence: the hourglass observations meant it may even be genetically controlled rather than socially.

Lankester joked that he saw this kind of degeneration in many men when they inherit a fortune.  But his idea backfired seriously when it was taken up by conservatives who cherished evolution as the Creator’s domain. They still argued in the 1880s that God had put humans at the top of a mountain of complexity, the argument that Lamarck had begun in 1809. If the respectable Dr Jekyll created the damnable young Mr Hyde, so other top humans could control lower forms by Lankester’s device of degeneration. The idea encouraged well-known Victorian thinkers such as Herbert Spencer and Samuel Butler to turn against Darwin’s words and twist them to their own ends. Humans do have some control over parts of the environment though the full consequences of this were not clear to anyone in their day.

There was also much that angered Lankester about the fashionable pursuit of spiritualism that swept Britain and North America through the 1870s and 1880s. The very assumption of contacting the dead, let alone the process and practice of communicating with them was too much for a scientist to take seriously. And certainly this process was serious for millions of people then, sitting at cloth-covered tables, in heavily curtained dim drawing rooms, where every sound was heard with suspicion and hope. To Lankester’s mind it was a proposition that was there only to be falsified, and that is what he set out to do.

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An event in 1876 gave him a wonderful opportunity and stimulated him to challenge some of those involved. It was a remarkable address given to the British Association by none other than Alfred Wallace who spoke in support of spiritualism as a scientifically valid process. That evening, Lankester wrote a letter to The Times complaining that the lecture had brought the Association and science into disrepute. The rumpus that followed attracted the full glare of publicity and involved Lankester prosecuting one of Wallace’s spiritualist friends for fraud. The hearing at Bow Street Magistrate’s Court lasted several weeks and attracted huge public interest. Wallace spoke in the defendant’s favour, as did Arthur Conan Doyle, while a professional illusionist showed how the trick could have been performed. Wallace’s friend was found guilty under the Vagrancy Act and after an Appeal he went back to the United States. The whole affair made séances far less fashionable and Ray Lankester became the most well-known professor in the country. But it didn’t do Alfred Wallace any good at all.

Lankester was a man of contradictions, not one to be taken in by any over-simplification of the complex systems of biology. He strongly believed that arguments were a necessary part of the way human intellect worked things out, and of how they are in nature. So although he strongly disagreed with a lot of the new criticism of natural selection, he did have secret admiration for some of the protagonists.

31. Uncertainty About Mendel 1904-1907

Useful though these biometric methods were to become, another fruitful line of enquiry was beginning in the United States. The mutations first described in plants by de Vries, and then recognised elsewhere by Bateson, were to be tackled really seriously by one of Lankester’s marine biology acquaintances, one who took delight in the switch from qualitative to quantitative outlooks. Thomas Hunt Morgan (1866-1945) was to win a Nobel Prize for his “discoveries concerning the role played by the chromosome in heredity” particularly in fruit flies. Although the penny that dropped on Bateson’s train journey in 1900 was heard clearly by Morgan, it took until 1933 for the Prize to be awarded and full public approval to be granted.

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When Morgan was a student at Woods Hole Marine Biological Laboratory in Massachusetts he had been interested in the embryology of sea spiders, to find out whether they were crustaceans or arachnids. But when he followed the footsteps of Lankester in 1894 to the marine laboratory in Naples, he became more interested in the chemical and physical changes that happened as the little creatures developed. From then on, TH Morgan saw no need for natural selection and believed that species had no reality in the flow of nature. “It appears that new species are born; they are not made by Darwinian methods, and the theory of natural selection has nothing to do with the origin of species, but with the survival of already formed ones.”  To him, a “naturalist” was the opposite of a “scientist” and biology could be explained in terms of physics and chemistry. This was despite him knowing very little of either and at the same time insisting that “genetics can be studied without any reference to evolution”. These were purist views, typical of the way an enthusiast supports a new idea if only to get it across. But they also showed the power of reduction to the smallest detail and the growing popularity of the quantitative approach.

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Morgan’s view was a restatement of the old supporters of Lamarck who thought that selection could not create but only reject. They failed to see that it was through this rejection that new forms are created and it was to be three decades later that Morgan’s students realised this. They agreed that evolution worked at many levels, whether it was with the mathematics of molecules and populations of organisms, with the physics and chemistry of genes, the chemistry of physiology and with the influence of different environments. By change at any of these levels, biodiversity came from the splitting of lineages, by speciation, and that gave discontinuity in nature. But it was mutations that mattered most to Morgan because he thought they created new species immediately, despite the environment. They also occurred in single genes and would become extinct only if the change was harmful for all individuals.

From 1904 Morgan moved to New York aiming to find the commonly suspected patterns of change that seemed to be continuously passing from one generation to another. By then the talk of Mendel’s ratios validating the role of sudden mutations gave him new hope and he started to look for evidence of what might be in control of these hereditary characters. That was when he started to work with fruit flies, which were easy to use in his laboratory, or the ‘fly room’ as he called it.

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This was more than just a room, rather a very well-organised and well-led group of enthusiasts who were in at the beginning of experimental genetics. Drosophila flies were cheap, quick and easy to breed in milk bottles, and the features they inherited showed up very noticeably. They also had just four very large chromosomes that showed changes in shape and colour in different parts, ideal for examining chromosomal events during the sexual and asexual cycles of cell division, how they related to the structural features of the adult. Mutations came easily and bred true as variously coloured eyes, striped bodies, wings of different shapes and such like. But these techniques were going to need thousands of experiments before any trends emerged and even then the data were not going to be easy to analyse and interpret. Like the processes they were monitoring the experiments needed to be fully controlled and monitored.

In 1907 Bateson visited Yale and set out his post-Mendelian statement about genetics and evolution. He fought for the slow and gradual recombinations that Mendel’s work had described and for which he had proposed the word “genetics” two years earlier. But there was still no evidence that any particles on the chromosomes or anywhere else were the agents of inheritance. Bateson kept quiet then about his thoughts on the train in 1900 when he also remembered another article by a German cytologist Theodor Boveri. That was about structures inside the cell nuclei of sea urchin embryos, structures the author had called chromosomes. Could the recombined ratios, he wondered, come from a re-sorting of particles on these chromosomes during sexual reproduction, both in peas and sea urchins?

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Bateson preferred to think that vibrations were the more likely agent: “In Mendelian analysis we have now, it is true, something comparable with the clue of chemistry, but there is little prospect of penetrating the obscurity which envelops the mechanical aspect of our phenomena.” Inheritance must be transmitted by a force from physics, vibration. “Patterns mechanically produced are of many and very diverse kinds. One of the most familiar examples, and one presenting some especially striking analogies to organic patterns, is that provided by the ripples of a mackerel sky, or those made in a flat sandy beach by the wind or the ebbing tide.”

It came as no surprise that Bateson and Morgan were very different kinds of people, and they did not get on. Morgan looked a bit like Weldon with a droopy moustache, and he had a casual and laid-back southern outlook on life. Bateson thought Morgan “rough”, “of no considerable account” and “dreadfully small” and even reported to his wife that “TH Morgan is a thickhead”. At first, in 1907, about the only thing they had in common was that chromosomes were not of much significance in genetics.

Both men had nothing to say about natural selection or Darwin or the link between his ideas and Mendel’s ratios of inheritance. Instead, based as much on envy as on reason, Bateson gave Morgan, and the audience at Yale, his own eccentric idea, but with no new evidence. Instead, because he couldn’t leave his vibration theory alone, he could only offer a sad and weak attempt to get the idea across. “I think we are entitled to the inference that in the formation of patterns in animals and plants mechanical forces are operating which ought to be, and will prove to be, capable of mathematical analysis.”

Bateson left America without changing anyone’s mind about the cause of evolution, let alone his own. Many of the different ways of explaining evolution were still possibilities though they all had different levels of support and very few people could appreciate how each idea might fit into the whole picture of a living system. There was some support for vibrations, and evidence for degeneration, a case for eugenics and mutation as well as for Darwin’s more gradual theory of natural selection. Without evidence from genetics, geological dating, biogeography, migration or ecology, no single theory or investigator stood out as the most acceptable. There was still all to play for in the game of trying to understand how life worked. Although new disciplines had begun in the four decades since the Origin was published, none had given any major new advance. What little seemed acceptable was split up, all in bits.

One thing was for sure, the way to understand Mendel’s results was going to be through some quantitative assessment, and Lankester organised a series of monthly dinners at his club to help find a way through. On such occasions there was a lot of talk about the biometric work coming from Galton’s laboratory and how it might inform those hoping for selective human breeding. Two mathematicians in the group, Whitehead and Russell, were preparing to work on their monumental Principia Mathematica, and they wanted to link Lankester’s descriptive biology to their own quantitative methods, but it was going to be difficult at first. th

Bertrand Russell (1872-1970) was best placed to link these topical issues because he was one of the few people who could understand both languages. As a philosopher with mathematical skills, he was in the right place at the right time. Together with Whitehead he advocated three requirements to explain the history of life: a concept of infinity, the flexibility of choice, and the desire to reduce explanations to the smallest component. This rigorous and optimistic programme was raising the stakes of biologists, pushing qualitative description to one side and claiming biometricians as heroes.

Even Lankester appreciated that this was the way things were going and was pleased to explain that the new methods relied on descriptive data. And all around in science there was a shortage of data; numbers were highly sought after and soon there were plenty of non-scientists interested in mathematics solely as a mental exercise. This was summed up by one presentation in Cambridge that attracted a large audience when Bertrand Russell teamed up with TS Eliot reciting the value of pi for ten minutes. There was then a period of meditation before they continued with another hundred or more decimal places of the constant’s value. It was going to be important for biologists to keep mathematics under control.

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What the old brigade of Wallace and Lankester saw as being even more difficult than describing life by equations was the link these mathematicians, outsiders to their classical biology, had with their philosopher friends in Vienna. It was the group that Rudolf Carnap was to lead for the next two decades and which at this early stage became known as the First Vienna Circle. These men met at the Cafe Central and had a very clear vision of where philosophy was going. They saw all knowledge coming together as a single language of science, becoming more and more precise and leading to a single truth, one Law of Life being verifiable by experiments and taken further by mathematical modelling.

Russell was never an inside member of this group and later went out of his way to distance himself, despite the excellent credentials that his three explanation of life gave him for membership. Instead, he experienced an incident that his Principia Mathematica could not account for and which would have been rejected as irrelevant by the First Vienna Circle. It was from a simple incident of seeing the pain felt by a lonely woman as she was growing old, all alone. “Having for years cared only for exactness and analysis, I found myself filled with semi-mystical feelings about beauty …. to find some philosophy which should make human life endurable.”

By then, measuring was seen to be an essential part of the scientific routine and few young biologists were sympathetic to Russell’s feelings about the old lady’s values of life: instead they searched for other explanations. One such person was in the same city of Vienna at the same time as the philosophers, Paul Kammerer (1880-1926), an experimental zoologist. He wanted to prove Lamarkian theories of evolution by breeding reptiles such as toads and salamanders. Kammerer’s first experiments involved breeding midwife toads in warm water and after several new generations he noticed the growth of black nuptial pads on the males’ feet to keep grip on the female.

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Other toad species also had these pads, and Kammerer explained them all as adaptations to the slippery conditions. This didn’t prove or disprove Lamarck, but it did help understand something about toad life-styles. Usually the males could grip their mate easily and didn’t slip on dry land, but in the moist conditions of Kammerer’s experiments they kept sliding around. The question people were asking was whether the pads came from the expression of an existing trait, inherited from a line of ancestral species that also mated in water, or whether the pads were from a new mutation. Kammerer himself was unsure of the answer when he began this work in 1906 and didn’t come to favour the explanation that they were from rapid mutations until after the war.

With the measured scientist and philosophers at the Cafe Central and experimentalists like Kammerer, Vienna was hardening into a place of scientific rigour for the twentieth century. Not least of importance was an ear-nose-and-throat doctor, Wilhelm Fliess, who also reckoned to have helped turn biology into a science describable by mathematics. For more than ten years he had gathered data from cyclical body patterns such as 28 day menstruation and an associated periodicity of 23 days. He compared these to times of nasal bleeding, and even dates of birth and death and concocted an arithmetic formula to account for many other bodily functions as well. Fliess’s best friend was Sigmund Freud who entrusted his own nose to Fliess’s surgery, despite another patient nearly dying from similar treatment. The surgery was thought to be a cure for Freud’s arrhythmic heart beat and was regarded as a great success. It was also at the time of Freud’s entrance into life science, when he began to link human psychology to evolutionary biology.

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(Rudolph Carnap)               (Central Cafe, Viena)                                           (Freud and Fliess 1895)

Francis Galton had already been thinking about this other ghost of Darwin, how study of the mammalian mind might fit in with evolutionary mechanisms. To open up his enquiries he began to subject some of the results from his Anthropometric Laboratory to his first statistical methods of analysis. He had the height measurements of thousands of parents and their children and plotted them out in different ways. Not surprisingly, taller parents tended to have taller children, but the children were rarely taller than the parents. Equally, shorter parents had only slighter shorter children. There was a tendency to revert back towards the average.

This way of measuring association between any two like-with-like variables, such as heights of parents with heights of children, helped Galton find a standard that he applied to other closely comparable data. Two variables are often closely associated for correlations as well as regressions, similarities as well as differences. They formed the basis of much more sophisticated biometric applications, weather forecasts, economic indicators and even public opinion polls. But in all cases the quality of the prediction was no better than the quality of the data used in the first place.