Freud seemed to believe (following Bain and others) that the reason for the unconscious tendency to unify opposites is the relativity of all scales by which attributes are measured: a 'hot' summer-day in London is 'cold' to the visitor from the Sudan, and Gulliver is a 'giant' or a 'dwarf' according to the country he visits. He further refers to the fact that in some ancient languages pairs of opposites are designated by the same word: thus altus means both 'high' and 'deep', and sacer both 'holy' and 'accursed'.
For once, however, Freud did not seem to have probed deep enough; he did not mention the rites of the Saturnalia and other ancient festivals, in which the roles of slaves and masters are reversed; nor the constant affirmation of the unity of opposites in most Oriental religions and philosophies. It seems indeed that the tendency to stand things, from time to time, on their head, has its deep, unconscious roots, which probably reach down into the physiological peculiarities of the nervous system.* One of its striking manifestations is the reversibility of 'figure' and 'background' in visual perception -- about which below.
I am not at all sure how far these considerations are relevant to a certain pattern of discovery which recurs with curious insistence in the biological sciences: we find, over and again, mishaps and minor laboratory disasters which turn out to be blessings in disguise, and spoilt experiments which perversely yield the solution -- by brutally shifting the experimenter's attention from a 'plus' to a 'minus' aspect of the problem, as it were. One might call this pattern 'discovery by misadventure'. A classic case is that of the Abbé Haüy (1743-1822), a humble teacher at the college at Lemoine, whose leisure hours were devoted to collecting specimens of plants and minerals -- until a small, embarrassing accident suddenly changed the direction of his interests and his whole life:
One day, when examining some minerals at the house of a friend, he was clumsy enough to allow a beautiful cluster of prismatic crystals of calcareous spar to fall on the ground. One of the prisms broke in such a way as to show at the fracture faces which were no less smooth than those elsewhere, but presented the appearance of a new crystal altogether different in form from the prism. Haüy picked up this fragment and examined the faces with their inclinatious and angles. To his great surprise, he discovered that they are the same in rhomboidal spar as in Iceland spar. He wished to be able to generalize: he broke his own little collection into pieces; crystals lent by his friends were broken; everywhere he found a structure which depended upon the same laws. [11]
The result was Haüy's Traité de Mineralogie which made him a member of the French Academy and a pioneer of the science of crystallography.
Haüy had a favourite pupil, Delafosse, who later became Pasteur's teacher at the École Normale in Paris. Under his influence Pasteur took up the study of crystallography; it was in this field that he made his first important discoveries, which contained the germs of all his later achievements. The decisive incident was again a laboratory mishap.
Pasteur was studying his favourite mineral, Para-Tartrate, derived from the red Tartar deposit in the vats of fermented wine. One day one of his Tartrate solutions became affected by a mould, and spoiled. This kind of thing frequently happens in warm weather; the normal reaction of chemists is to pour, with a gentle oath, the turbid liquid down the drain. Pasteur reversed the logic of the situation: he shifted his attention to the accidental and irrelevant mould, and turned 'accident' into 'experiment' by studying the mould's action on the Tartrate. The result was 'the first link in the chain of arguments which led him into the study of fermentation, to the recognition that micro-organisms play an essential role in the economy of nature, and eventually to his epoch-making discoveries in the field of infectious diseases'.
In his later life Pasteur performed the same kind of mental head-stand on at least two more momentous occasions. One I have already mentioned: the discovery of immunization by vaccines, which grew out of a spoilt culture of chicken cholera. The other was the 'domestication' of micro-organisms, their transformation from enemies into allies of man, which led to industrial micro-biology and, eventually, to the antibiotics: microbes destroying microbes. 'In the inferior organisms,' he wrote, 'still more than in the big animal and vegetable species, life hinders life.' It sounds simple. But what a long way it was from the enunciation of the principle to the discovery of penicillin! It took more than half a century; and it was again due to an almost ludicrous series of misadventures. They started in 1922, when Alexander Fleming caught a cold. A drip from his nose fell into a dish in his laboratory at St. Mary's Hospital; the nasal slime killed off the bacilli in the culture; Fleming isolated the active agent in the mucus, which was also present in tears, and called it lysozyme. That was the first step; but lysozyme was not powerful enough as a germ-killer, and another seven years had to pass until a gust of wind blew through the lab window a spore of the mould penicillium notatum, which happened to settle in a culture dish of staphylococci. But Fleming had been waiting for that stroke of luck for fifteen years; and when it came, he was ready for it. As Lenin has said somewhere: 'If you think of Revolution, dream of Revolution, sleep with Revolution for thirty years, you are bound to achieve a Revolution one day.'
I shall have to return to Fleming in a different context. The examples of 'discovery by misadventure', which I have just given, were taken from biology; but the same kind of perverse- or reverse-logic can also be found operating in other branches of science and art.
In 1821 Faraday invented the electric motor, and constructed a crude model of it. For more than fifty years no attention was paid to his invention. In 1831 he also invented (independently from, and roughly simultaneously with Joseph Henry) the electrical dynamo. A motor converts electric current into mechanical motion; a dynamo converts mechanical motion into electricity. But, curiously, the reciprocal nature of the two machines was not realized until 1873. By that time huge dynamo machines, driven by steam power, were in use to generate electrial current; but Faraday's earlier invention had been forgotten, and electric motors did not exist.
In 1873, at an exhibition in Vienna, several dynamo machines of an improved type were displayed. In the happy-go-lucky manner of the Austrians, one of the technicians mistakenly connected a dynamo, driven by a steam-engine, with a second dynamo which was at rest. The current fed into the resting dynamo promptly set it into motion -- and thus the electrical motor came into existence. Electric trains, the electrical trammission of power, one of the foundations of modern technology, originates in the accidental reversal of the function of a single machine.
The history of photography and the early history of radiography seem to hinge on fluorescent screens and photographic plates which showed effects they were not supposed to show, and vice versa. Daguerre put an exposed plate into an untidy cupboard full of various bottles of chemicals -- including some mercury. The next morning he found to his surprise that a perfect image had developed on the plate. He repeated the experiment, systematically eliminating one chemical after another in the cupboard -- until he knew that it was mercury vapour which had done the trick. Prior to the discovery of mercury as an ideal developer of latent images, Daguerre had written: 'The time required to procure a photographic copy of a landscape is from seven to eight hours; but single monuments, when strongly lighted by the sun, or which are themselves very bright, can be taken in about three hours.' [12] After the discovery, the time of exposure was shortened to between three and thirty minutes.
In 1895 Wilhelm Konrad Röntgen, Professor of Physics at the University of Würzburg, noticed by accident that a paper-screen covered with barium platinocyanide became fluorescent without any apparent cause. He had at the time a cathode-ray tube going -- an apparatus used to study the conduction of electricity through gases -- which was enclosed in a box of black cardboard. But in those days there was no radiation known hard enough to penetrate black cardboard, and such a thing was in fact considered to be impossible. Röntgen immediately accepted the impossible as true: the fluorescent glow which he saw on t
he screen must be caused by rays of an unknown kind, emitted by the tube, and capable of traversing the black cardboard. Within a few weeks he had demonstrated that the rays were equally capable of traversing human flesh and showing the outline of the bones as shadows cast upon the luminous screen. He called them X-rays.
Some few weeks later, Henri Becquerel saw a demonstration of Röntgen's X-rays at a meeting of the French Academy of Sciences. Becquerel's father and grandfather had also been professors of physics and members of the Academy; they had taken a special interest in the fluorescent glow which certain substances -- among them uranium compounds -- emit, when exposed to light. He therefore immediately formed the -- wrong -- theory that X-rays were a normal accompaniment of the fluorescent glow, and he set out to prove this theory by experiment. He wrapped a photographic plate into heavy black paper to screen it from ordinary light. On top of the paper-wrapping he laid some crystals of the uranium compound; between the crystals and the wrapping he placed a bit of metal with holes in it. Then he placed this whole arrangement outside his window so that the sun's rays should set the uranium aglow with fluorescence, and thereby set the X-rays going across the wrapper. This worked admirably: when he developed his plates the rays had penetrated the wrapping and produced a photograph of the holes in the metal. It was a wonderful example of an experiment confirming a prediction based on a false hypothesis.
No sooner had he communicated his results to the Academy, when the sky clouded over, and Becquerel put his plates and the uranium into a dark drawer. Here the crystals were shut off from the sunlight; hence there was no fluorescent glow; hence there could be no X-rays to blacken the photographic plate. But when he took them out of the drawer, the plates were blackened nevertheless. Once more the impossible had happened; and once more a reversal of logic brought the solution. The fluorescent glow had been caused by the X-rays -- and not the other way round. Becquerel now tried non-fluorescent uranium compounds and found that they, too, produced rays. He tried other fluorescent materials which did not contain uranium, and found that they did not produce the rays. That clinched the matter: the source of the rays, the radio-active agent, was the uranium itself. It was from here that the Curies took over.
Perhaps the prettiest example of reasoning in reverse gear is the invention of the phonograph.
As a young man Edison worked as a telegraphist. His main job was the taking of messages from the Morse-ticker by ear; if the line was bad, the ticking became blurred, and he had to rely on guessing. This annoyed him all the more as, owing to an earlier accident, Edison was partially deaf. So the young telegraphist invented a simple Morse-signal-recording apparatus. It consisted mainly of a paper disc, which was made to rotate like the gramophone disc of the future; on the disc the incoming dots and dashes were recorded as indentations. But from the telegraph company's point of view transcribing from the record instead of doing it directly by ear from the ticker was a sheer waste of time; Edison, then seventeen, lost his job.
Eleven years later, in the first laboratory of his own, he was working on about fifty inventions simultaneously -- among them the typewriter and an improved telegraph-recorder, on which the incoming dots and dashes were embossed by a needle. When the message was to be sent on to another station, the paper disc was placed on a transmitting machine with a contact lever which moved up and down according to the indentations on the disc. It was a gadget with the sole purpose of recording and transmitting electrical impulses, and had nothing whatsoever to do with the production of sounds. Yet it did produce purely accidental sounds -- because the lever, while tracing the embossed dots and dashes, was apt to rattle; and when the disc was rotated very quickly this rattle became a hum, then something like a musical sound. A sudden reversal of logic and the phonograph was born.
The rest was a matter of elaboration. Instead of a paper disc, Edison proposed to use a cylinder covered with soft tin-foil; instead of attaching the needie to a Morse-telegraph, he attached it to a membrane set into vibration by the waves of sound. He made a sketch of the machine, and gave it to one of his workmen, a certain John Kruesi. It cost altogether eighteen dollars to build it, but Kruesi had no idea what the contraption was for. When it was finished Edison shouted at it: 'Mary had a little lamb.' Then he turned the handle of the recording cylinder:
'The machine reproduced perfectly. Everybody was astonished. . . . ' And that was that. To quote once more the jargon of communication engineering: the background 'noise' of the vibrating lever had been turned into 'information'.
We have met the same kind of logical mirror-writing in humour -- 'a sadist is a person who is kind to a masochist', 'operation successful, patent dead'. All jokes based on a turning-the-tables technique show the same pattern (for instance, the Prince and the Retainer story on p. 84).
In the classical tragedy, on the other hand, it is the gods, or the stars, who turn the tables on the mortal hero, or lure him into appointments in Samara. They particularly like to use seemingly harmless coincidences -- the blind gaps in the meaningful order of events -- as levers of destiny. In later forms of literature, it is characters which are made to stand on their heads, or are turned inside out like a glove. Prince Mishkin, the 'Idiot', is revealed as a sage in reverse; saints are sinners, sinners are saints, heroes are cowards, adults are children, and every Jekyll has something to Hyde.
In visual perception we find a parallel phenomenon in the reversible figure-background relation. If one stares at the mosaic on the bathroom floor, unconscious and often uncontrollable shifts in perception make the pattern of black tiles stand out at one moment, and the pattern of white tiles at the next. A more dramatic illustration is the following, found in many psychological textbooks:
Urn or profiles -- whichever is master for a while, will become slave in turn, 'figure' will change into 'ground', 'noise' into 'information', in a kind of visual saturnalia. The two perceptual matrices are reciprocal, and their alternation seems to be determined by unconscious physiological processes.
Some of the great revolutions in the history of painting entailed almost equally brutal reversals of vision. Up to the late Venetians, the landscape on the canvas was primarily perceived as a conventional background against which human figures were displayed; roughly from Giorgione onward it became possible to paint landscapes in which the human figure played an accidental part. At different stages one finds similar reversals in the logic of the eye: from ornate drapery to personal expression, from contours to surfaces, from naturalism to other isms of perception. At each of these upheavals the cat without a grin was superseded by the grin without a cat.
In the realm of music the relativity and reversibility of 'figure' and 'background' (accompaniment, counterpoint, fugue) is self-evident. It is less obvious in modern theoretical physics, although it is implied in one of its basic postulates: according to Niels Bohr's "Principle of Contemplementary" the ultimate constituents of the universe -- electrons, protons, photons, etc. -- behave on some occasions as if they were particles, that is, hard lumps of matter, on other occasions as if they were ripples of energy without definite location. Although the two descriptions are mutually exclusive in terms of traditional physics and philosophy, the theory works remarkably well. As a matter of fact, most physicists are not much bothered by the inherent contradiction, and are quite content to believe that the 'wavicles', the actual stuff the world is made of, are at one moment like the solid urn, and the next like the empty space between the two profiles.
That the most brilliant scientists of this century should be capable of accepting this paradox is a rather striking indication of the susceptibility of the human mind for reversals of logic, and the unification of opposites. The complementarity of energy and matter in quantum-physics is not so far removed as it would seem from the dualism of Yang and Yin, the feminine and masculine principles in Taoist philosophy. I do not mean that Lao-Tse, in the sixth century B.C., foresaw the behaviour of alpha-particles in a Wilson chamber; I mean that it is a timeless chara
cteristic of the unconscious mind to work in that way.
Analogy and Intuition
The great biologist Elie Mechnikoff felt rather lonely one afternoon in 1890 'when the whole family had gone to the circus to see some extraordinary performing apes, and I remained alone with my microscope'. [13] The microscope was in a laboratory of the École Normale which Pasteur had given him; Mechuikoff was observing the life of the mobile cells in the transparent larvae of starfish, and idly threw a few rose-thorns among them. The thorns were promptly surrounded by the larvae and dissolved inside their transparent bodies -- they had been gobbled up and digested. This reminded him of what happens when a human finger is infected by a splinter: it will be surrounded by pus which, like the starfish larvae, will attack and try to digest the intruder. By this analogy Mechnikoff discovered the organisms' main defence mechanism against invading microbes: the 'phagocytes', cell-eaten, a population of mobile cells among the white blood corpuscles.
The starting point of Kepler's discoveries was a supposed analogy between the role of the Father in the Trinity and the role of the Sun in the Universe. Lord Kelvin hit on the idea of the mirror galvanometer when he noticed a reflection of light on his monocle. Sultan saw that a branch was like a stick; Newton saw that the moon behaved like an apple. Pasteur saw the analogy between a spoilt culture and a cow-pox vaccine; Fleming saw the analogy between the action of a mould and the action of a drip from his nose. Freud, on his own account, conceived the idea of the sublimation of instincts by looking at a funny cartoon in the Fliegende Blätter -- the one-time German equivalent of Punch. In the first picture a little girl was herding a flock of goslings with a stick. In the second she had grown into a governess herding a flock of young ladies with a parasol. [14]