Modern Mind: An Intellectual History of the 20th Century

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DISTURBING THE PEACE

The year 1900 A.D. need not have been remarkable. Centuries are man-made conventions after all, and although people may think in terms of tens and hundreds and thousands, nature doesn’t. She surrenders her secrets piecemeal and, so far as we know, at random. Moreover, for many people around the world, the year 1900 A.D. meant little. It was a Christian date and therefore not strictly relevant to any of the inhabitants of Africa, the Americas, Asia, or the Middle East. Nevertheless, the year that the West chose to call 1900 was an unusual year by any standard. So far as intellectual developments – the subject of this book – were concerned, four very different kinds of breakthrough were reported, each one offering a startling reappraisal of the world and man’s place within it. And these new ideas were fundamental, changing the landscape dramatically.

The twentieth century was less than a week old when, on Saturday, 6 January, in Vienna, Austria, there appeared a review of a book that would totally revise the way man thought about himself. Technically, the book had been published the previous November, in Leipzig as well as Vienna, but it bore the date 1900, and the review was the first anyone had heard of it. The book was entitled The Interpretation of Dreams, and its author was a forty-four-year-old Jewish doctor from Freiberg in Moravia, called Sigmund Freud.¹ Freud, the eldest of eight children, was outwardly a conventional man. He believed passionately in punctuality. He wore suits made of English cloth, cut from material chosen by his wife. Very self-confident as a young man, he once quipped that ‘the good impression of my tailor matters to me as much as that of my professor.’² A lover of fresh air and a keen amateur mountaineer, he was nevertheless a ‘relentless’ cigar smoker.³ Hanns Sachs, one of his disciples and a friend with whom he went mushrooming (a favourite pastime), recalled ‘deep set and piercing eyes and a finely shaped forehead, remarkably high at the temples.’⁴ However, what drew the attention of friends and critics alike was not the eyes themselves but the look that shone out from them. According to his biographer Giovanni Costigan, ‘There was something baffling in this look – compounded partly of intellectual suffering, partly of distrust, partly of resentment.’⁵

There was good reason. Though Freud might be a conventional man in his personal habits, The Interpretation of Dreams was a deeply controversial and – for many people in Vienna – an utterly shocking book. To the world outside, the Austro-Hungarian capital in 1900 seemed a gracious if rather antiquated metropolis, dominated by the cathedral, whose Gothic spire soared above the baroque roofs and ornate churches below. The court was stuck in an unwieldy mix of pomposity and gloom. The emperor still dined in the Spanish manner, with all the silverware laid to the right of the plate.⁶ The ostentation at court was one reason Freud gave for so detesting Vienna. In 1898 he had written, ‘It is a misery to live here and it is no atmosphere in which the hope of completing any difficult thing can survive.’⁷ In particular, he loathed the ‘eighty families’ of Austria, ‘with their inherited insolence, their rigid etiquette, and their swarm of functionaries.’ The Viennese aristocracy had intermarried so many times that they were in fact one huge family, who addressed each other as Du, and by nicknames, and spent their time at each others’ parties.⁸ This was not all Freud hated. The ‘abominable steeple of St Stefan’ he saw as the symbol of a clericalism he found oppressive. He was no music lover either, and he therefore had a healthy disdain for the ‘frivolous’ waltzes of Johann Strauss. Given all this, it is not hard to see why he should loathe his native city. And yet there are grounds for believing that his often-voiced hatred for the place was only half the picture. On II November 1918, as the guns fell silent after World War I, he made a note to himself in a memorandum, ‘Austria-Hungary is no more. I do not want to live anywhere else. For me emigration is out of the question. I shall live on with the torso and imagine that it is the whole.’⁹

The one aspect of Viennese life Freud could feel no ambivalence about, from which there was no escape, was anti-Semitism. This had grown markedly with the rise in the Jewish population of the city, which went from 70,000 in 1873 to 147,000 in 1900, and as a result anti-Semitism had become so prevalent in Vienna that according to one account, a patient might refer to the doctor who was treating him as ‘Jewish swine.’¹⁰ Karl Lueger, an anti-Semite who had proposed that Jews should be crammed on to ships to be sunk with all on board, had become mayor.¹¹ Always sensitive to the slightest hint of anti-Semitism, to the end of his life Freud refused to accept royalties from any of his works translated into Hebrew or Yiddish. He once told Carl Jung that he saw himself as Joshua, ‘destined to explore the promised land of psychiatry.’¹²

A less familiar aspect of Viennese intellectual life that helped shape Freud’s theories was the doctrine of ‘therapeutic nihilism.’ According to this, the diseases of society defied curing. Although adapted widely in relation to philosophy and social theory (Otto Weininger and Ludwig Wittgenstein were both advocates), this concept actually started life as a scientific notion in the medical faculty at Vienna, where from the early nineteenth century on there was a fascination with disease, an acceptance that it be allowed to run its course, a profound compassion for patients, and a corresponding neglect of therapy. This tradition still prevailed when Freud was training, but he reacted against it.¹³ To us, Freud’s attempt at treatment seems only humane, but at the time it was an added reason why his ideas were regarded as out of the ordinary.

Freud rightly considered The Interpretation of Dreams to be his most significant achievement. It is in this book that the four fundamental building blocks of Freud’s theory about human nature first come together: the unconscious, repression, infantile sexuality (leading to the Oedipus complex), and the tripartite division of the mind into ego, the sense of self; superego, broadly speaking, the conscience; and id, the primal biological expression of the unconscious. Freud had developed his ideas – and refined his technique – over a decade and a half since the mid–1880s. He saw himself very much in the biological tradition initiated by Darwin. After qualifying as a doctor, Freud obtained a scholarship to study under Jean-Martin Charcot, a Parisian physician who ran an asylum for women afflicted with incurable nervous disorders. In his research Charcot had shown that, under hypnosis, hysterical symptoms could be induced. Freud returned to Vienna from Paris after several months, and following a number of neurological writings (on cerebral palsy, for example, and on aphasia), he began a collaboration with another brilliant Viennese doctor, Josef Breuer (1842—1925). Breuer, also Jewish, was one of the most trusted doctors in Vienna, with many famous patients. Scientifically, he had made two major discoveries: on the role of the vagus nerve in regulating breathing, and on the semicircular canals of the inner ear, which, he found, controlled the body’s equilibrium. But Breuers importance for Freud, and for psychoanalysis, was his discovery in 1881 of the so-called talking cure.¹⁴ For two years, beginning in December 1880, Breuer had treated for hysteria a Vienna-born Jewish girl, Bertha Pappenheim (1859—1936), whom he described for casebook purposes as ‘Anna O.’ Anna fell ill while looking after her sick father, who died a few months later. Her illness took the form of somnambulism, paralysis, a split personality in which she sometimes behaved as a naughty child, and a phantom pregnancy, though the symptoms varied. When Breuer saw her, he found that if he allowed her to talk at great length about her symptoms, they would disappear. It was, in fact, Bertha Pappenheim who labelled Breuer’s method the ‘talking cure’ (Redecur in German) though she also called it Kaminfegen – ‘chimney sweeping.’ Breuer noticed that under hypnosis Bertha claimed to remember how she had repressed her feelings while watching her father on his sickbed, and by recalling these ‘lost’ feelings she found she could get rid of them. By June 1882 Miss Pappenheim was able to conclude her treatment, ‘totally cured’ (though it is now known that she was admitted within a month to a sanatorium).¹⁵

The case of Anna O. deeply impressed Freud. For a time he himself tried hypnosis with hysterical patients but abandoned this approach, replacing it with ‘free association’ – a technique whereby he allowed his patients to talk about whatever came into their minds. It was this technique that led to his discovery that, given the right circumstances, many people could recall events that had occurred in their early lives and which they had completely forgotten. Freud came to the conclusion that though forgotten, these early events could still shape the way people behaved. Thus was born the concept of the unconscious, and with it the notion of repression. Freud also realised that many of the early memories revealed – with difficulty – under free association were sexual in nature. When he further found that many of the ‘recalled’ events had in fact never taken place, he developed his notion of the Oedipus complex. In other words the sexual traumas and aberrations falsely reported by patients were for Freud a form of code, showing what people secretly wanted to happen, and confirming that human infants went through a very early period of sexual awareness. During this period, he said, a son was drawn to the mother and saw himself as a rival to the father (the Oedipus complex) and vice versa with a daughter (the Electra complex). By extension, Freud said, this broad motivation lasted throughout a person’s life, helping to determine character.

These early theories of Freud were met with outraged incredulity and unremitting hostility. Baron Richard von Krafft-Ebing, the author of a famous book, Psychopathia Sexualis, quipped that Freud’s account of hysteria ‘sounds like a scientific fairy tale.’ The neurological institute of Vienna University refused to have anything to do with him. As Freud later said, ‘An empty space soon formed itself about my person.’¹⁶

His response was to throw himself deeper into his researches and to put himself under analysis – with himself. The spur to this occurred after the death of his father, Jakob, in October 1896. Although father and son had not been very intimate for a number of years, Freud found to his surprise that he was unaccountably moved by his father’s death, and that many long-buried recollections spontaneously resurfaced. His dreams also changed. He recognised in them an unconscious hostility directed toward his father that hitherto he had repressed. This led him to conceive of dreams as ‘the royal road to the unconscious.’¹⁷ Freud’s central idea in The Interpretation of Dreams was that in sleep the ego is like ‘a sentry asleep at its post.’¹⁸ The normal vigilance by which the urges of the id are repressed is less efficient, and dreams are therefore a disguised way for the id to show itself. Freud was well aware that in devoting a book to dreams he was risking a lot. The tradition of interpreting dreams dated back to the Old Testament, but the German title of the book, Die Traumdeutung, didn’t exactly help. ‘Traumdeutung’ was the word used at the time to describe the popular practice of fairground fortune-tellers.¹⁹

The early sales for The Interpretation of Dreams indicate its poor reception. Of the original 600 copies printed, only 228 were sold during the first two years, and the book apparently sold only 351 copies during its first six years in print.²⁰ More disturbing to Freud was the complete lack of attention paid to the book by the Viennese medical profession.²¹ The picture was much the same in Berlin. Freud had agreed to give a lecture on dreams at the university, but only three people turned up to hear him. In 1901, shortly before he was to address the Philosophical Society, he was handed a note that begged him to indicate ‘when he was coming to objectionable matter and make a pause, during which the ladies could leave the hall.’ Many colleagues felt for his wife, ‘the poor woman whose husband, formerly a clever scientist, had turned out to be a rather disgusting freak.’²²

But if Freud felt that at times all Vienna was against him, support of sorts gradually emerged. In 1902, a decade and a half after Freud had begun his researches, Dr Wilhelm Stekel, a brilliant Viennese physician, after finding a review of The Interpretation of Dreams unsatisfactory, called on its author to discuss the book with him. He subsequently asked to be analysed by Freud and a year later began to practise psychoanalysis himself. These two founded the ‘Psychological Wednesday Society,’ which met every Wednesday evening in Freud’s waiting room under the silent stare of his ‘grubby old gods,’ a reference to the archaeological objects he collected.²³ They were joined in 1902 by Alfred Adler, by Paul Federn in 1904, by Eduard Hirschmann in 1905, by Otto Rank in 1906, and in 1907 by Carl Gustav Jung from Zurich. In that year the name of the group was changed to the Vienna Psychoanalytic Society and thereafter its sessions were held in the College of Physicians. Psychoanalysis had a good way to go before it would be fully accepted, and many people never regarded it as a proper science. But by 1908, for Freud at least, the years of isolation were over.

In the first week of March 1900, amid the worst storm in living memory, Arthur Evans stepped ashore at Candia (now Heraklion) on the north shore of Crete.²⁴ Aged 49, Evans was a paradoxical man, ‘flamboyant, and oddly modest; dignified and loveably ridiculous…. He could be fantastically kind, and fundamentally uninterested in other people…. He was always loyal to his friends, and never gave up doing something he had set his heart on for the sake of someone he loved.’²⁵ Evans had been keeper of the Ashmolean Museum in Oxford for sixteen years but even so did not yet rival his father in eminence. Sir John Evans was probably the greatest of British antiquaries at the time, an authority on stone hand axes and on pre-Roman coins.

By 1900 Crete was becoming a prime target for archaeologists if they could only obtain permission to dig there. The island had attracted interest as a result of the investigations of the German millionaire merchant Heinrich Schliemann (1822–1890), who had abandoned his wife and children to study archaeology. Undeterred by the sophisticated reservations of professional archaeologists, Schliemann forced on envious colleagues a major reappraisal of the classical world after his discoveries had shown that many so-called myths – such as Homer’s Iliad and Odyssey – were grounded in fact. In 1870 he began to excavate Mycenae and Troy, where so much of Homer’s story takes place, and his findings transformed scholarship. He identified nine cities on the site of Troy, the second of which he concluded was that described in the Iliad.²⁶

Schliemann’s discoveries changed our understanding of classical Greece, but they raised almost as many questions as they answered, among them where the brilliant pre-Hellenic civilisation mentioned in both the Iliad and the Odyssey had first arisen. Excavations right across the eastern Mediterranean confirmed that such a civilisation had once existed, and when scholars reexamined the work of classical writers, they found that Homer, Hesiod, Thucydides, Herodotus, and Strabo had all referred to a King Minos, ‘the great lawgiver,’ who had rid the Aegean of pirates and was invariably described as a son of Zeus. And Zeus, again according to ancient texts, was supposed to have been born in a Cretan cave.²⁷ It was against this background that in the early 1880s a Cretan farmer chanced upon a few large jars and fragments of pottery of Mycenaean character at Knossos, a site inland from Candia and two hundred and fifty miles from Mycenae, across open sea. That was a very long way in classical times, so what was the link between the two locations? Schliemann visited the spot himself but was unable to negotiate excavation rights. Then, in 1883, in the trays of some antiquities dealers in Shoe Lane in Athens, Arthur Evans came across some small three- and four-sided stones perforated and engraved with symbols. He became convinced that these symbols belonged to a hieroglyphic system, but not one that was recognisably Egyptian. When he asked the dealers, they said the stones came from Crete.²⁸ Evans had already considered the possibility that Crete might be a stepping stone in the diffusion of culture from Egypt to Europe, and if this were the case it made sense for the island to have its own script midway between the writing systems of Africa and Europe (evolutionary ideas were everywhere, by now). He was determined to go to Crete. Despite his severe shortsightedness, and a propensity for acute bouts of seasickness, Evans was an enthusiastic traveller.²⁹ He first set foot in Crete in March 1894 and visited Knossos. Just then, political trouble with the Ottoman Empire meant that the island was too dangerous for making excavations. However, convinced that significant discoveries were to be made there, Evans, showing an initiative that would be impossible today, bought part of the Knossos grounds, where he had observed some blocks of gypsum engraved with a system of hitherto unknown writing. Combined with the engravings on the stones in Shoe Lane, Athens, this was extremely promising.³⁰

Evans wanted to buy the entire site but was not able to do so until 1900, by which time Turkish rule was fairly stable. He immediately launched a major excavation. On his arrival, he moved into a ‘ramshackle’ Turkish house near the site he had bought, and thirty locals were hired to do the initial digging, supplemented later by another fifty. They started on 23 March, and to everyone’s surprise made a significant find straight away.³¹ On the second day they uncovered the remains of an ancient house, with fragments of frescoes – in other words, not just any house, but a house belonging to a civilisation. Other finds came thick and fast, and by 27 March, only four days into the dig, Evans had already grasped the fundamental point about Knossos, which made him famous beyond the narrow confines of archaeology: there was nothing Greek and nothing Roman about the discoveries there. The site was much earlier. During the first weeks of excavation, Evans uncovered more dramatic material than most archaeologists hope for in a lifetime: roads, palaces, scores of frescoes, human remains – one cadaver still wearing a vivid tunic. He found sophisticated drains, bathrooms, wine cellars, hundreds of pots, and a fantastic elaborate royal residence, which showed signs of having been burned to the ground. He also unearthed thousands of clay tablets with ‘something like cursive writing’ on them.³² These became known as the fabled Linear A and B scripts, the first of which has not been deciphered to this day. But the most eye-catching discoveries were the frescoes that decorated the plastered walls of the palace corridors and apartments. These wonderful pictures of ancient life vividly portrayed men and women with refined faces and graceful forms, and whose dress was unique. As Evans quickly grasped, these people – who were contemporaries of the early biblical pharaohs, 2500–1500 B.C. — were just as civilised as them, if not more so; indeed they outshone even Solomon hundreds of years before his splendour would become a fable among Israelites.³³

Evans had in fact discovered an entire civilisation, one that was completely unknown before and could claim to have been produced by the first civilised Europeans. He named the civilisation he had discovered the Minoan because of the references in classical writers and because although these Bronze Age Cretans worshipped all sorts of animals, it was a bull cult, worship of the Minotaur, that appeared to have predominated. In the frescoes Evans discovered many scenes of bulls – bulls being worshipped, bulls used in athletic events and, most notable of all, a huge plaster relief of a bull excavated on the wall of one of the main rooms of Knossos Palace.

Once the significance of Evans’s discoveries had sunk in, his colleagues realised that Knossos was indeed the setting for part of Homer’s Odyssey and that Ulysses himself goes ashore there. Evans spent more than a quarter of a century excavating every aspect of Knossos. He concluded, somewhat contrary to what he had originally thought, that the Minoans were formed from the fusion, around 2000 B.C., of immigrants from Anatolia with the native Neolithic population. Although this people constructed towns with elaborate palaces at the centre (the Knossos Palace was so huge, and so intricate, it is now regarded as the Labyrinth of the Odyssey), Evans also found that large town houses were not confined to royalty only but were inhabited by other citizens as well. For many scholars, this extension of property, art, and wealth in general marked the Minoan culture as the birth of Western civilisation, the ‘mother culture’ from which the classical world of Greece and Rome had evolved.³⁴

Two weeks after Arthur Evans landed in Crete, on 24 March 1900, the very week that the archaeologist was making the first of his great discoveries, Hugo de Vries, a Dutch botanist, solved a very different – and even more important – piece of the evolution jigsaw. In Mannheim he read a paper to the German Botanical Society with the title ‘The Law of Segregation of Hybrids.’

De Vries – a tall, taciturn man – had spent the previous years since 1889 experimenting with the breeding and hybridisation of plants, including such well-known flowers as asters, chrysanthemums, and violas. He told the meeting in Mannheim that as a result of his experiments he had formed the view that the character of a plant, its inheritance, was ‘built up out of definite units’; that is, for each characteristic – such as the length of the stamens or the colour of the leaves – ‘there corresponds a particular form of material bearer.’ (The German words was in fact Träger, which may also be rendered as ‘transmitter.’) And he added, most significantly, ‘There are no transitions between these elements.’ Although his language was primitive, although he was feeling his way, that night in Mannheim de Vries had identified what later came to be called genes.³⁵ He noted, first, that certain characteristics of flowers – petal colour, for example – always occurred in one or other form but never in between. They were always white or red, say, never pink. And second, he had also identified the property of genes that we now recognise as ‘dominance’ and ‘recession,’ that some forms tend to predominate over others after these forms have been crossed (bred). This was a major discovery. Before the others present could congratulate him, however, he added something that has repercussions to this day. ‘These two propositions’, he said, referring to genes and dominance/recession, ‘were, in essentials, formulated long ago by Mendel…. They fell into oblivion, however, and were misunderstood…. This important monograph [of Mendel’s] is so rarely quoted that I myself did not become acquainted with it until I had concluded most of my experiments, and had independently deduced the above propositions.’ This was a very generous acknowledgement by de Vries. It cannot have been wholly agreeable for him to find, after more than a decade’s work, that he had been ‘scooped’ by some thirty years.³⁶

The monograph that de Vries was referring to was ‘Experiments in Plant-Hybridisation,’ which Pater Gregor Mendel, a Benedictine monk, had read to the Brünn Society for the Study of Natural Science on a cold February evening in 1865. About forty men had attended the society that night, and this small but fairly distinguished gathering was astonished at what the rather stocky monk had to tell them, and still more so at the following month’s meeting, when he launched into a complicated account of the mathematics behind dominance and recession. Linking maths and botany in this way was regarded as distinctly odd. Mendel’s paper was published some months later in the Proceedings of the Brünn Society for the Study of Natural Science, together with an enthusiastic report, by another member of the society, of Darwin’s theory of evolution, which had been published seven years before. The Proceedings of the Brünn Society were exchanged with more than 120 other societies, with copies sent to Berlin, Vienna, London, St Petersburg, Rome, and Uppsala (this is how scientific information was disseminated in those days). But little attention was paid to Mendel’s theories.³⁷

It appears that the world was not ready for Mendel’s approach. The basic notion of Darwin’s theory, then receiving so much attention, was the variability of species, whereas the basic tenet of Mendel was the constancy, if not of species, at least of their elements. It was only thanks to de Vries’s assiduous scouring of the available scientific literature that he found the earlier publication. No sooner had he published his paper, however, than two more botanists, at Tubingen and Vienna, reported that they also had recently rediscovered Mendel’s work. On 24 April, exactly a month after de Vries had released his results, Carl Correns published in the Reports of the German Botanical Society a ten-page account entitled ‘Gregor Mendel’s Rules Concerning the Behaviour of Racial Hybrids.’ Correns’s discoveries were very similar to those of de Vries. He too had scoured the literature – and found Mendel’s paper.³⁸ And then in June of that same year, once more in the Reports of the German Botanical Society, there appeared over the signature of the Viennese botanist Erich Tschermak a paper entitled ‘On Deliberate Cross-Fertilisation in the Garden Pea,’ in which he arrived at substantially the same results as Correns and de Vries. Tschermak had begun his own experiments, he said, stimulated by Darwin, and he too had discovered Mendel’s paper in the Brünn Society Proceedings.³⁹ It was an extraordinary coincidence, a chain of events that has lost none of its force as the years have passed. But of course, it is not the coincidence that chiefly matters. What matters is that the mechanism Mendel had recognised, and the others had rediscovered, filled in a major gap in what can claim to be the most influential idea of all time: Darwin’s theory of evolution.

In the walled garden of his monastery, Mendel had procured thirty-four more or less distinct varieties of peas and subjected them to two years of testing. Mendel deliberately chose a variety (some were smooth or wrinkled, yellow or green, long-stemmed or short-stemmed) because he knew that one side of each variation was dominant – smooth, yellow, or long-stemmed, for instance, rather than wrinkled, green, or short-stemmed. He knew this because when peas were crossed with themselves, the first generation were always the same as their parents. However, when he self-fertilised this first generation, or F, as it was called, to produce an F₂ generation, he found that the arithmetic was revealing. What happened was that 253 plants produced 7,324 seeds. Of these, he found that 5,474 were smooth and 1,850 were wrinkled, a ratio of 2.96:1. In the case of seed colour, 258 plants produced 8,023 seeds: 6,022 yellow and 2,001 green, a ratio of 3.01:1. As he himself concluded, ‘In this generation along with the dominant traits the recessive ones appear in their full expression, and they do so in the decisively evident average proportion of 3:1, so that among the four plants of this generation three show the dominant and one the recessive character.’⁴⁰ This enabled Mendel to make the profound observation that for many characteristics, the heritable quality existed in only two forms, the dominant and recessive strains, with no intermediate form. The universality of the 3:1 ratio across a number of characteristics confirmed this.* Mendel also discovered that these characteristics exist in sets, or chromosomes, which we will come to later. His figures and ideas helped explain how Darwinism, and evolution, worked. Dominant and recessive genes governed the variability of life forms, passing different characteristics on from generation to generation, and it was this variability on which natural selection exerted its influence, making it more likely that certain organisms reproduced to perpetuate their genes.

Mendel’s theories were simple and, to many scientists, beautiful. Their sheer originality meant that almost anybody who got involved in the field had a chance to make new discoveries. And that is what happened. As Ernst Mayr has written in The Growth of Biological Thought, ‘The rate at which the new findings of genetics occurred after 1900 is almost without parallel in the history of science.’⁴¹

And so, before the fledgling century was six months old, it had produced Mendelism, underpinning Darwinism, and Freudianism, both systems that presented an understanding of man in a completely different way. They had other things in common, too. Both were scientific ideas, or were presented as such, and both involved the identification of forces or entities that were hidden, inaccessible to the human eye. As such they shared these characteristics with viruses, which had been identified only two years earlier, when Friedrich Löffler and Paul Frosch had shown that foot-and-mouth disease had a viral origin. There was nothing especially new in the fact that these forces were hidden. The invention of the telescope and the microscope, the discovery of radio waves and bacteria, had introduced people to the idea that many elements of nature were beyond the normal range of the human eye or ear. What was important about Freudianism, and Mendelism, was that these discoveries appeared to be fundamental, throwing a completely new light on nature, which affected everyone. The discovery of the ‘mother civilisation’ for European society added to this, reinforcing the view that religions evolved, too, meaning that one old way of understanding the world was subsumed under another, newer, more scientific approach. Such a change in the fundamentals was bound to be disturbing, but there was more to come. As the autumn of 1900 approached, yet another breakthrough was reported that added a third major realignment to our understanding of nature.

In 1900 Max Planck was forty-two. He was born into a very religious, rather academic family, and was an excellent musician. He became a scientist in spite of, rather than because of, his family. In the type of background he had, the humanities were considered a superior form of knowledge to science. His cousin, the historian Max Lenz, would jokingly refer to scientists (Naturforscher) as foresters (Naturförster). But science was Planck’s calling; he never doubted it or looked elsewhere, and by the turn of the century he was near the top of his profession, a member of the Prussian Academy and a full professor at the University of Berlin, where he was known as a prolific generator of ideas that didn’t always work out.⁴²

Physics was in a heady flux at the turn of the century. The idea of the atom, an invisible and indivisible substance, went all the way back to classical Greece. At the beginning of the eighteenth century Isaac Newton had thought of atoms as minuscule billiard balls, hard and solid. Early-nineteenth-century chemists such as John Dalton had been forced to accept the existence of atoms as the smallest units of elements, since this was the only way they could explain chemical reactions, where one substance is converted into another, with no intermediate phase. But by the turn of the twentieth century the pace was quickening, as physicists began to experiment with the revolutionary notion that matter and energy might be different sides of the same coin. James Clerk Maxwell, a Scottish physicist who helped found the Cavendish Laboratory in Cambridge, England, had proposed in 1873 that the ‘void’ between atoms was filled with an electromagnetic field, through which energy moved at the speed of light. He also showed that light itself was a form of electromagnetic radiation. But even he thought of atoms as solid and, therefore, essentially mechanical. These were advances far more significant than anything since Newton.⁴³

In 1887 Heinrich Hertz had discovered electric waves, or radio as it is now called, and then, in 1897, J. J. Thomson, who had followed Maxwell as director of the Cavendish, had conducted his famous experiment with a cathode ray tube. This had metal plates sealed into either end, and then the gas in the tube was sucked out, leaving a vacuum. If subsequently the metal plates were connected to a battery and a current generated, it was observed that the empty space, the vacuum inside the glass tube, glowed.⁴⁴ This glow was generated from the negative plate, the cathode, and was absorbed into the positive plate, the anode.*

The production of cathode rays was itself an advance. But what were they exactly? To begin with, everyone assumed they were light. However, in the spring of 1897 Thomson pumped different gases into the tubes and at times surrounded them with magnets. By systematically manipulating conditions, he demonstrated that cathode rays were in fact infinitesimally minute particles erupting from the cathode and drawn to the anode. He found that the particles’ trajectory could be altered by an electric field and that a magnetic field shaped them into a curve. He also discovered that the particles were lighter than hydrogen atoms, the smallest known unit of matter, and exactly the same whatever the gas through which the discharge passed. Thomson had clearly identified something fundamental. This was the first experimental establishment of the particulate theory of matter.⁴⁵

This particle, or ‘corpuscle,’ as Thomson called it at first, is today known as the electron. With the electron, particle physics was born, in some ways the most rigorous intellectual adventure of the twentieth century which, as we shall see, culminated in the atomic bomb. Many other particles of matter were discovered in the years ahead, but it was the very notion of particularity itself that interested Max Planck. Why did it exist? His physics professor at the University of Munich had once told him as an undergraduate that physics was ‘just about complete,’ but Planck wasn’t convinced.⁴⁶ For a start, he doubted that atoms existed at all, certainly in the Newtonian/Maxwell form as hard, solid miniature billiard balls. One reason he held this view was the Second Law of Thermodynamics, conceived by Rudolf Clausius, one of Planck’s predecessors at Berlin. The First Law of Thermodynamics may be illustrated by the way Planck himself was taught it. Imagine a building worker lifting a heavy stone on to the roof of a house.⁴⁷ The stone will remain in position long after it has been left there, storing energy until at some point in the future it falls back to earth. Energy, says the first law, can be neither created nor destroyed. Clausius, however, pointed out in his second law that the first law does not give the total picture. Energy is expended by the building worker as he strains to lift the stone into place, and is dissipated in the effort as heat, which among other things causes the worker to sweat. This dissipation Clausius termed ‘entropy’, and it was of fundamental importance, he said, because this energy, although it did not disappear from the universe, could never be recovered in its original form. Clausius therefore concluded that the world (and the universe) must always tend towards increasing disorder, must always add to its entropy and eventually run down. This was crucial because it implied that the universe was a one-way process; the Second Law of Thermodynamics is, in effect, a mathematical expression of time. In turn this meant that the Newton/Maxwellian notion of atoms as hard, solid billiard balls had to be wrong, for the implication of that system was that the ‘balls’ could run either way – under that system time was reversible; no allowance was made for entropy.⁴⁸

In 1897, the year Thomson discovered electrons, Planck began work on the project that was to make his name. Essentially, he put together two different observations available to anyone. First, it had been known since antiquity that as a substance (iron, say) is heated, it first glows dull red, then bright red, then white. This is because longer wavelengths (of light) appear at moderate temperatures, and as temperatures rise, shorter wavelengths appear. When the material becomes white-hot, all the wavelengths are given off. Studies of even hotter bodies – stars, for example – show that in the next stage the longer wavelengths drop out, so that the colour gradually moves to the blue part of the spectrum. Planck was fascinated by this and by its link to a second mystery, the so-called black body problem. A perfectly formed black body is one that absorbs every wavelength of electromagnetic radiation equally well. Such bodies do not exist in nature, though some come close: lampblack, for instance, absorbs 98 percent of all radiation.⁴⁹ According to classical physics, a black body should only emit radiation according to its temperature, and then such radiation should be emitted at every wavelength. In other words, it should only ever glow white. In Planck’s Germany there were three perfect black bodies, two of them in Berlin. The one available to Planck and his colleagues was made of porcelain and platinum and was located at the Bureau of Standards in the Charlottenburg suburb of the city.⁵⁰ Experiments there showed that black bodies, when heated, behaved more or less like lumps of iron, giving off first dull red, then bright red-orange, then white light. Why?

Planck’s revolutionary idea appears to have first occurred to him around 7 October 1900. On that day he sent a postcard to his colleague Heinrich Rubens on which he had sketched an equation to explain the behaviour of radiation in a black body.⁵¹ The essence of Planck’s idea, mathematical only to begin with, was that electromagnetic radiation was not continuous, as people thought, but could only be emitted in packets of a definite size. Newton had said that energy was emitted continuously, but Planck was contradicting him. It was, he said, as if a hosepipe could spurt water only in ‘packets’ of liquid. Rubens was as excited by this idea as Planck was (and Planck was not an excitable man). By 14 December that year, when Planck addressed the Berlin Physics Society, he had worked out his full theory.⁵² Part of this was the calculation of the dimensions of this small packet of energy, which Planck called h and which later became known as Planck’s constant. This, he calculated, had the value of 6.55 × 10^–27 ergs each second (an erg is a small unit of energy). He explained the observation of black-body radiation by showing that while the packets of energy for any specific colour of light are the same, those for red, say, are smaller than those of yellow or green or blue. When a body is first heated, it emits packets of light with less energy. As the heat increases, the object can emit packets with greater energy. Planck had identified this very small packet as a basic indivisible building block of the universe, an ‘atom’ of radiation, which he called a ‘quantum.’ It was confirmation that nature was not a continuous process but moved in a series of extremely small jerks. Quantum physics had arrived.

Not quite. Whereas Freud’s ideas met hostility and de Vries’s rediscovery of Mendel created an explosion of experimentation, Planck’s idea was largely ignored. His problem was that so many of the theories he had come up with in the twenty years leading up to the quantum had proved wrong. So when he addressed the Berlin Physics Society with this latest theory, he was heard in polite silence, and there were no questions. It is not even clear that Planck himself was aware of the revolutionary nature of his ideas. It took four years for its importance to be grasped – and then by a man who would create his own revolution. His name was Albert Einstein.

On 25 October 1900, only days after Max Planck sent his crucial equations on a postcard to Heinrich Rubens, Pablo Picasso stepped off the Barcelona train at the Gare d’Orsay in Paris. Planck and Picasso could not have been more different. Whereas Planck led an ordered, relatively calm life in which tradition played a formidable role, Picasso was described, even by his mother, as ‘an angel and a devil.’ At school he rarely obeyed the rules, doodled compulsively, and bragged about his inability to read and write. But he became a prodigy in art, transferring rapidly from Malaga, where he was born, to his father’s class at the art school in Corunna, to La Llotja, the school of fine arts in Barcelona, then to the Royal Academy in Madrid after he had won an award for his painting Science and Charity. However, for him, as for other artists of his time, Paris was the centre of the universe, and just before his nineteenth birthday he arrived in the City of Light. Descending from his train at the newly opened station, Picasso had no place to stay and spoke almost no French. To begin with he took a room at the Hôtel du Nouvel Hippodrome, a maison de passe on the rue Caulaincourt, which was lined with brothels.⁵³ He rented first a studio in Montparnasse on the Left Bank, but soon moved to Montmartre, on the Right.

Paris in 1900 was teeming with talent on every side. There were seventy daily newspapers, 350,000 electric streetlamps and the first Michelin guide had just appeared. It was the home of Alfred Jarry, whose play Ubu Roi was a grotesque parody of Shakespeare in which a fat, puppetlike king tries to take over Poland by means of mass murder. It shocked even W. B. Yeats, who attended its opening night. Paris was the home of Marie Curie, working on radioactivity, of Stephane Mallarmé, symbolist poet, and of Claude Debussy and his ‘impressionist music.’ It was the home of Erik Satie and his ‘atonally adventurous’ piano pieces. James Whistler and Oscar Wilde were exiles in residence, though the latter died that year. It was the city of Emile Zola and the Dreyfus affair, of Auguste and Louis Lumière who, having given the world’s first commercial showing of movies in Lyons in 1895, had brought their new craze to the capital. At the Moulin Rouge, Henri de Toulouse-Lautrec was a fixture; Sarah Bernhardt was a fixture too, in the theatre named after her, where she played the lead role in Hamlet en travesti. It was the city of Gertrude Stein, Maurice Maeterlinck, Guillaume Apollinaire, of Isadora Duncan and Henri Bergson. In his study of the period, the Harvard historian Roger Shattuck called these the ‘Banquet Years,’ because Paris was celebrating, with glorious enthusiasm, the pleasures of life. How could Picasso hope to shine amid such avant-garde company?⁵⁴

Even at the age of almost nineteen Picasso had already made a promising beginning. A somewhat sentimental picture by him, Last Moments, hung in the Spanish pavilion of the great Exposition Universelle of 1900, in effect a world’s fair held in both the Grand and the Petit Palais in Paris to celebrate the new century.⁵⁵ Occupying 260 acres, the fair had its own electric train, a moving sidewalk that could reach a speed of five miles an hour, and a great wheel with more than eighty cabins. For more than a mile on either side of the Trocadero, the banks of the Seine were transformed by exotic facades. There were Cambodian temples, a mosque from Samarkand, and entire African villages. Below ground were an imitation gold mine from California and royal tombs from Egypt. Thirty-six ticket offices admitted one thousand people a minute.⁵⁶ Picasso’s contribution to the exhibition was subsequently painted over, but X rays and drawings of the composition show a priest standing over the bed of a dying girl, a lamp throwing a lugubrious light over the entire scene. The subject may have been stimulated by the death of Picasso’s sister, Conchita, or by Giacomo Puccini’s opera La Bohème, which had recently caused a sensation when it opened in the Catalan capital. Last Moments had been hung too high in the exhibition to be clearly seen, but to judge by a drawing Picasso made of himself and his friends joyously leaving the show, he was pleased by its impact.⁵⁷

To coincide with the Exposition Universelle, many distinguished international scholarly associations arranged to have their own conventions in Paris that year, in a building near the Pont d’Alma specially set aside for the purpose. At least 130 congresses were held in the building during the year and, of these, 40 were scientific, including the Thirteenth International Congress of Medicine, an International Congress of Philosophy, another on the rights of women, and major get-togethers of mathematicians, physicists, and electrical engineers. The philosophers tried (unsuccessfully) to define the foundations of mathematics, a discussion that floored Bertrand Russell, who would later write a book on the subject, together with Alfred North Whitehead. The mathematical congress was dominated by David Hilbert of Göttingen, Germany’s (and perhaps the world’s) foremost mathematician, who outlined what he felt were the twenty-three outstanding mathematical problems to be settled in the twentieth century.⁵⁸ These became known as the ‘Hilbert questions’. Many would be solved, though the basis for his choice was to be challenged fundamentally.

It would not take Picasso long to conquer the teeming artistic and intellectual world of Paris. Being an angel and a devil, there was never any question of an empty space forming itself about his person. Soon Picasso’s painting would attack the very foundations of art, assaulting the eye with the same vigour with which physics and biology and psychology were bombarding the mind, and asking many of the same questions. His work probed what is solid and what is not, and dived beneath the surface of appearances to explore the connections between hitherto unapprehended hidden structures in nature. Picasso would focus on sexual anxiety, ‘primitive’ mentalities, the Minotaur, and the place of classical civilisations in the light of modern knowledge. In his collages he used industrial and mass-produced materials to play with meaning, aiming to disturb as much as to please. (‘A painting,’ he once said, ‘is a sum of destructions.’) Like that of Darwin, Mendel, Freud, J. J. Thomson and Max Planck, Picasso’s work challenged the very categories into which reality had hitherto been organised.⁵⁹

Picasso’s work, and the extraordinary range of the exposition in Paris, underline what was happening in thought as the 1800s became the 1900s. The central points to grasp are, first, the extraordinary complementarity of many ideas at the turn of the century, the confident and optimistic search for hidden fundamentals and their place within what Freud, with characteristic overstatement, called ‘underworlds’; and second, that the driving motor in this mentality, even when it was experienced as art, was scientific. Amazingly, the backbone of the century was already in place.

* The 3:1 ratio may be explained in graphic form as follows:

where Y is the dominant form of the gene, and y is the recessive.

* This is also the basis of the television tube. The positive plate, the anode, was reconfigured with a glass cylinder attached, after which it was found that a beam of cathode rays passed through the vacuum towards the anode made the glass fluoresce.