The Invisible Century: Einstein, Freud and the Search for Hidden Universes

Maybe so. Whatever it was, it was over now, as if a fever had broken. The problem that Freud had found himself confronting was larger than pathways of nerves, larger than the neuron itself—or, maybe, smaller. Either way, it was the same problem that had been haunting physiology since the inception of the modern era more than two centuries earlier: brain. To be precise, it was brain in opposition to what the motions of matter within the human cranium represent: mind, maybe.

For much of human history, such a distinction would have been secondary, at best. The far more important distinction, instead, would have been the one between two types of matter: terrestrial and celestial. Down here, as Aristotle had said, were the four elements—earth, air, fire, and water, either alone or in any number of combinations. Up there was one element—quintessence, a single perfect substance that constituted the moon, sun, planets and stars, as well as the spheres that carried them on their heavenly journeys. An Earth that itself traveled through the heavens, however, not only erased the crucial distinction between what was terrestrial and what was celestial but—as Descartes appreciated when he was merely a budding philosopher—presented a strong argument that everything in heaven and everything on Earth might ultimately consist of the same stuff.

Descartes first heard about Galileo’s discovery of four moons orbiting Jupiter in 1610, as a student at the Jesuit college at La Flèche. Although Descartes was only thirteen or fourteen when this astonishing news reached his outpost in the French countryside, he understood at once the profound effects such a discovery could have on philosophy and physics. The very scope of those effects, however, also reinforced for him two growing suspicions: that although philosophy “has been cultivated for many centuries by the most excellent minds,” as he later wrote, “there is still no point in it which is not disputed and hence doubtful”; and that as “for the other sciences, in so far as they borrow their principles from philosophy I decided that nothing solid could have been built upon such shaky foundations.” The only rational approach to this appalling and ongoing state of ignorance, he concluded, was to begin again, from the beginning—“to demolish everything completely and start right again from the foundations,” and to do so by seeking “no knowledge other than that which could be found in myself or else in the great book of the world.”

The World, in fact, was what he called his first attempt to explain all of physics. As was often the case with Descartes when he produced a work of physics, he simultaneously produced a companion work on how a reconception of physics would necessitate a new interpretation of man’s role in it—a new physiology. This work he called Treatise on Man. He completed both in 1633, a year after Galileo released his own attempt at a new physics, Dialogue Concerning the Two Chief World Systems. But before his two volumes could reach publication, Descartes heard that the Roman Catholic Church had condemned Galileo because the Dialogue posited a sun-centered universe. Since his own two essays did the same and since he feared that if he altered them in any way they would be “mangled,” Descartes suppressed both.

But he never stopped working on physics and physiology. In particular, over the next few years, he wondered if the newfound conceptual unity between the heavens and the Earth would allow him to achieve a parallel mathematical unity. In other words, could he do to the terrestrial realm what astronomers had long done to the celestial realm: geometricize it? Geometry, after all, had originally been an attempt to render the terrestrial world in mathematical terms. Now, after a lapse of a couple of millennia, it was again, and in his 1637 Geometry, Descartes demonstrated how all matter, not only in heaven but on Earth, could be located according to three coordinates in space. In which case, as Descartes himself recognized and as succeeding generations came to appreciate, a crucial question presented itself: Could we approach the secrets of man’s inner universe with the same heretofore unthinkable curiosity that Galileo and his successors had regarded the outer? Could we render the motions of matter within the brain as predictable as any planet’s through the heavens? In short, could there be a Newton of neurology?

Even while Newton was alive and evidence had begun to accumulate that his laws extend to the outermost reaches of the universe, the question inevitably had arisen whether those same laws might extend to the innermost reaches as well. In 1725, Richard Mead, an English physician, had produced mathematical formulations of the effects of planetary gravity on the human body. Expanding on that idea later in the eighteenth century, the German physician Franz Anton Mesmer proposed a gravitational attraction between animals, or what he called animal magnetism, whose existence he then claimed to demonstrate through public displays of hypnotism. In the early nineteenth century, efforts at quantifying psychic phenomena found a champion in the German philosopher Johann Friedrich Herbart, who conceived of the workings of the mind as “forces” rather than ideas, who explicitly invoked Newton in advocating the use of mathematical formulas to describe the motions of these forces, and who once declared, “Regular order in the human mind is wholly similar to that in the starry sky.”

In retrospect, though, any such earlier efforts to reduce the workings of the inner universe to a series of cause-and-effect laws were doomed. These would-be Newtons couldn’t have known it at the time, but they didn’t yet have access to a Galilean equivalent of neuroanatomical data—the moons, planets, and stars of the inner universe—to provide their speculations with a solid empirical foundation.

Did Freud? It was tempting for him to think so. It would have been tempting for anyone in his position to think so—not only because it’s always tempting for an ambitious intellect to think that the generation into which it’s fortunate enough to be born is the one in possession of just enough information to settle a question that has thwarted the great thinkers since antiquity but because the state of neuroanatomical knowledge at the close of the nineteenth century was different from any other period in the history of science. In fact, in 1894—only five years after Ramón y Cajal’s discovery that fibers from central nerve cells contact, not connect, and only three years after Waldeyer developed the neuron theory—one of Freud’s former instructors and colleagues from his laboratory days, Sigmund Exner, published his own attempt at a comprehensive neuroanatomy, Entwurf zu einer physiologischen Erklärung der psychischen Erscheinungen (Draft Toward a Physiological Explanation of the Psychological Features).

Like most physiologists of his era, Freud knew firsthand what the achromatic microscope could accomplish. He’d used the still-new instrument extensively as a student in the 1870s, then proved his mastery of it the following decade as a reliable, respected diagnostician at the General Hospital of Vienna, where one of his examinations drew praise in a contemporary medical journal for its “very valuable contribution” to a field “heretofore lacking in detailed microscopic examination.” And like many physiologists of his era, Freud knew firsthand what staining a microscopic sample could accomplish. He’d twice developed his own significant improvements on existing staining methods, first in 1877 “for the purpose of preparing in a guaranteed and easy way the central and peripheral nervous system of the higher vertebrate (mice, rabbits, cattle),” and again in 1883 “for the study of nerve tracts in the brain and spinal cord.” And like a few physiologists of his era, Freud had even anticipated the neuron theory itself, during his lecture before the Vienna Psychiatric Society in the early 1880s, several years before Ramón y Cajal proved it. Unable to locate a fiber that he could trace from one central nerve cell to another, he’d wondered if cells might therefore not ultimately connect.

In the wake of his failure with the “Psychology for Neurologists,” however, Freud began to consider another way to frame the problem: not as mind in opposition to brain—or at least not only mind in opposition to brain. Instead he began to think in terms of mind in opposition to itself.

“The starting-point for this investigation,” Freud later wrote, outlining his reasoning at this juncture, “is provided by a fact without parallel, which defies all explanation or description—the fact of consciousness.” On the most basic level, the workings of the mind remained a mystery. Even a thought, the fundamental unit of mind, doesn’t remain in consciousness for any length of time. “A conception—or any other psychical element—which is now present to my consciousness may become absent the next moment, and may become present again, after an interval, unchanged.” Forget for the moment the gap within the brain—between one neuron and the next, that space across which some “quantity” of “energy” must pass, as he’d tried to express the transaction in his “Psychology.” And forget, too, the gap between brain and mind—between the physical communication among neurons and the resulting psychical impressions. With this description of one of the most mundane of human occurrences—something out of “our most daily personal experience”—Freud had identified a gap within the mind itself: “In the interval the idea was—we do not know what.”

“Unconscious,” he called it, adopting the common adjective of the time. In a sense, all he’d done was work his way back to the assumptions that he and his contemporaries had inherited. Mind was mind, brain was brain, and one day, maybe, the two would meet. Brain anyone with the proper training and equipment could tease the secrets out of, slicing tissue, staining samples, subjecting fibrils to microscopic scrutiny at recently unthinkable powers of magnification and degrees of resolution. Mind, however, nobody could fully capture using a mechanical model of the brain—not yet, anyway. Mind, as Freud could observe for himself on an almost daily basis in his private medical practice, was simply full of too many subtleties whose precise nature continued to doom any attempt to do for the physical workings of the inner universe what Newton had done for the outer.

But, in another sense, what Freud had learned through the experience of writing that manuscript was just how subde the subtleties of mind were. Nothing in his neurological training had prepared him for—or, as he had now learned the hard way, could account for—that. Under intensive scrutiny, the mind had turned out to be even more complicated—far more circuitous, far more contradictory, and, finally, far more elusive—than he or, as far as he knew, anyone else had begun to imagine. Brain might be simply brain, but mind wasn’t just mind.

As he reclined in a chair in his modest study in Vienna, listening to the complaints of patients week after week, year after year, Freud had learned to encourage them to try to see whether they could remember the trauma that had caused their hysterical symptoms. If they did so, as he tried to reassure them, their symptoms would disappear. Freud had first heard about this method many years earlier, back in 1882, from a friend and colleague in Vienna, the eminent physician and medical researcher Josef Breuer. At that time, Breuer had told Freud about how he’d treated a young woman’s hysteria through hypnosis. Freud, in fact, had seen a demonstration of hypnosis once. It was, he thought, impressive, especially for a student with a physiological turn of mind. But instructive? Curative?

It might be so, said Breuer. Rather than simply issuing a command or a prohibition while she was under hypnosis, he said, he had asked this patient—Anna O., Freud named her later, when recalling this period in his professional development—what the source of the trauma was. In her waking state she “could describe only very imperfectly or not at all” the memories relating to her trauma, as Freud later wrote; in a hypnotic state, however, she seemed oddly able to remember everything. Even more improbably, by recalling the source of the trauma, as well as by experiencing the emotional outpouring that invariably accompanied this memory, she seemed somehow to slip free of the grip of the memory—seemed to achieve, in Breuer’s term, a “catharsis.”

In order for this construct of a cure to hold, it might seem, the mind must work like a Newtonian machine: an initial cause leading to an effect, which in turn becomes a cause for another effect, which in turn becomes another cause for a further effect, and so on, insinuating itself throughout the subject’s life until one day, in an unrecognizable guise, it surfaces as hysteric behavior, those worrisome symptoms that prompt the victim to seek medical attention. But if this description of the process were true, then the removal of any link along the way would be sufficient to interrupt the chain of causality and lead to the removal of the ultimate effect—the hysterical symptom. In that case, using hypnosis in a purely suggestive way, by simply commanding the symptom to disappear, would be sufficient in effecting a cure.

Freud, however, believed that he’d seen otherwise. When he attempted to apply this kind of therapy in his own medical practice, he found that leading the patient back to some step between the current state of hysteria and the original inciting incident didn’t have a cathartic result. Only by revisiting the scene of the crime, so to speak, could a victim permanently break free of its memory, its insidious influence. Only by tracing it to its source would doctor and patient see the hysterical symptom disappear—but only by tracing it all the way to its source. As Freud told a meeting of the Vienna Medical Club in January 1893, “The moment at which the physician finds out the occasion when the symptom first appeared and the reason for its appearance is also the moment at which the symptom vanishes.”

Anna O., for instance, complained of a paralysis on her right side, persistent hallucinations of snakes in her hair, and a sudden inability to speak her native German. These symptoms Breuer eventually traced back to an evening when she was nursing her sick father and imagined a snake approaching his sleeping figure. She tried to move to save him, but her right arm had gone to sleep over the back of a chair; and so she resorted to prayer, but in her fear all she could recall were some children’s verses in English. Or, from Freud’s own case files, Frau Cäcilie M., who suffered from a pain between her eyes until she remembered the time her grandmother had fixed her with a “piercing” look. “Cessante causa cessat effectus,” as Freud said in that same lecture before the Vienna Medical Club: “When the cause ceases, the effect ceases.”

Freud, however, wasn’t content with a vision of the mind that began with a cause and then, no matter what, ended with a certain effect. How to account for the inability of a process so powerful—so active, after all—to reveal itself?

With his background in a physiology that was ultimately nothing more than matter and motion, Freud knew exactly how to account for it: by postulating the existence within the unconscious of an opposing force at least equally powerful—a “defense” or, as Freud soon came to call it, a “repression,” a change in terminology that itself reflected a change in Freud’s thinking. This opposing force wasn’t merely defending the mind against itself; it was repressing the unpleasant memory or association. It wasn’t reactive. It, too, was active, even while seemingly absent.

On October 26, 1896, Freud’s father died. The heroic figure of Sigmund’s childhood imagination may have disappeared forever during that long-ago walk when the father confided in the son how he’d submitted to the indignities of an anti-Semite, and now the corporeal figure was gone, too. Yet they lingered—both the heroic figure and the tragic shade. Like a traumatic event that remains present in the symptoms of a hysterical patient, the older man remained alive in the grown son. That night, in fact, Freud had a dream about him. On his way to the funeral, Freud stops at a barbershop. There he sees a sign: “You are requested to close the eyes.” Whose eyes? he had to wonder. The dead father’s? The son’s? And “close” them as in lay to rest? Or “close” them as in “wink at” or “overlook”?

The dead-but-not-gone father wasn’t the only thing that lingered. The dream did, too, taunting Freud with its myriad possible interpretations, haunting him like the earlier memory of the about-to-be-unheroic man on the street, inhabiting him, continuing to exert its influence over him, as an adult, decades after the event. In years to come, Freud more formally commemorated his father’s death as “the most important event, the most poignant loss, of a man’s life.” But now, when his impressions were raw, he confided in a letter to his friend Fliess, “By one of those dark pathways behind the official consciousness the old man’s death has affected me deeply.”

Could Freud navigate those dark pathways? When he tried to map the pathways of nerves within the brain, he had failed—and now he suspected it was because he’d set himself the wrong challenge. Now a new and radically different challenge presented itself to him: How to map the pathways of the mind alone? Even if he could, would anyone believe that such a description bears any resemblance to reality? He would, of course—but then, sitting in his office, listening to his patients, Sigmund Freud had heard the evidence for himself, if only in his mind’s ear.

THREE GOING TO EXTREMES

Now here was something nobody had ever seen before. The photograph that began appearing on the front pages of newspapers around the world in the first weeks of 1896 showed an image of a hand, more or less. Less, because this hand seemed to lack skin—or at least its outer layers of flesh and blood and tendons had been reduced to a presence sufficiently shadowy so as to allow a look beneath them. And more, because of what that look within revealed: the intricate webwork of bones that previously had been solely the province of the anatomist.

The hand belonged to the wife of Wilhelm Conrad Röntgen, a professor at the University of Würzburg in Germany. On November 8, 1895, while working alone in his darkened laboratory, Professor Röntgen had noticed a seemingly inexplicable glow. On closer inspection, this glow revealed mysterious properties. For the next several weeks Röntgen worked in secrecy, strictly adhering to the method that had initiated the Scientific Revolution more than two centuries earlier and had sustained it ever since: He made sure that anyone else could use a Hittorf-Crookes tube and a Ruhmkorff coil to produce and reproduce the effect he’d detected. Sometimes his wife, Bertha, would ask why he was spending so much time in his laboratory, and he would answer that he was working on something that, if word got out, would have people saying, “Der Röntgen ist wohl verruckt geworden” (“Röntgen has probably gone crazy”).

At last Röntgen satisfied himself that his discovery was legitimate—that he hadn’t somehow misinterpreted the data. On December 22, he invited Bertha to join him in the laboratory, where he asked her to insert her hand, for fifteen minutes, between the tube and a photographic plate. As she did so, something happened—something he’d witnessed for himself numerous times now, something he still couldn’t explain. A substance passed between the tube and the plate—must have passed, because even though the substance itself was invisible, the effect was undeniable. An image of his wife’s hand, to her horror, was slowly burning itself into existence. On New Year’s Day, Röntgen went for a walk with Bertha, during which he mailed to colleagues copies of this photograph as well as his preliminary report, “Eine neue Art von Strahlen” (“A New Kind of Ray“)—what Röntgen, in a footnote, christened “X rays,” because of their mysterious nature. On the way to the mailbox, Röntgen turned to Bertha, whose hand—more or less, and complete (so to speak) with wedding ring—would soon be immortalized, and said, “Now the devil will have to be paid.”

The first public news account appeared on January 5, after a professor of physics at the University of Vienna received a copy of the paper and photograph and passed them along to colleagues, who in turn contacted the editor of the Wiener Presse. From there the news spread rapidly: the London Daily Chronicle on January 6, the Frankfurter Zeitung on January 7. “Men of science in this city,” began an article in The New York Times a few days later, “are awaiting with the utmost impatience the arrival of European technical journals”; when an English translation of Röntgen’s report arrived, the Times printed it on the front page almost in its entirety. By January 13 Röntgen had been summoned to Berlin, where he gave a demonstration of X-rays before Kaiser Wilhelm II. Röntgen granted only one substantive interview, to a particularly enterprising journalist from McClure’s Magazine, then withdrew from public scrutiny. “In a few days I was disgusted with the whole thing,” he later recalled. “I could not recognize my own work in the reports anymore.”

It was entirely coincidence that Röntgen had conducted what proved to be his decisive research at the same historical moment, and possibly even the same literal moment, that the sixteen-year-old Albert Einstein was pacing the grounds of a school in Aarau, trying to reconcile the properties of a beam of light with the concept of absolute space. It was similarly a coincidence that Röntgen made his discovery on the very day that the thirty-nine-year-old Sigmund Freud was writing to his friend Wilhelm Fliess that he was thinking of abandoning his attempt to render human thoughts strictly in terms of the motions of neuroanatomic matter. But it was no coincidence that speculation about the implications of Röntgen’s discovery led in the same direction that Einstein and Freud were already heading.

If X-rays were a “longitudinal vibration in the ether,” Thomas Edison pointed out to a journalist visiting his New Jersey laboratory, “then Professor Röntgen has found out at least one method of investigating [the ether’s] properties, and the gain to men of science in estimating the behavior of light and electricity through the medium of ether will probably be immense, causing many changes in our present theories.” Meanwhile, Science magazine reported that the College of Physicians and Surgeons in New York City had used the rays “to reflect anatomic diagrams directly into the brains of advanced medical students, making a much more enduring impression than ordinary teaching methods of learning anatomic details.” And whatever went into a skull presumably could also come out: A Mr. Ingles Rogers informed a San Francisco newspaper that he had “produced an impression on the photographic plate by simply gazing at it in the dark,” while a Dr. Baraduc attracted worldwide attention by sending an official communication to the Paris Académie de Médecin that he had succeeded in photographing thoughts, and he mounted an exhibition in Munich as proof. Or, as one early account regarding X-rays cautioned readers who would fool themselves into thinking that if they “go inside the house and pull down the blinds and wait till it is dark,” they might “feel quite safe in sinning”: “There are the x-rays, you know—and nobody knows what other invisible pencils may be registering all our actions or even thoughts—or what’s worse, the desires that we don’t dare think. They, too, must leave their mark somewhere.”

Nobody knew quite what X-rays were—not even Röntgen, though he did tentatively guess that they might indeed be longitudinal vibrations in the ether. And nobody knew quite what X-rays did—though the medical applications were apparent enough that by the following autumn The New York Times reported “no hospital in the land can do justice to its patients if it does not possess a complete X-ray outfit.” And nobody could have known what impact X-rays eventually would have on the history of science—revolutionary, but that’s getting ahead of the story. What anybody who cared about science did know by now, though, following more than two centuries of investigation, was that in the properties of the ether or the pathways of the brain the scientific method had reached the frontiers of the outer and inner universes.