Pathway to Japanese Literature

I The true origin of my artificial heart invention dates back to my first year at medical university, during a General Physiology lecture when I first heard the terms "artificial amoeba" and "artificial heart."...

Thus spoke Dr. A, the physiologist, to me. Dr. A had once been a man who struggled relentlessly to create an artificial heart—to craft one artificially that would replace the natural organ—thereby aiming to rescue humanity from various diseases, prolong life, and even achieve the feat of reviving the dead. Though this endeavor temporarily ruined his health and left him bedridden with grave illness, he neither wavered nor relented until finally accomplishing his goal once. Yet after his wife’s death, for reasons unknown, he discarded this hard-earned grand research like worn-out shoes and abandoned it entirely. I had frequently pressed him for an explanation, but Dr. A would only smirk tightly and seal his lips in stubborn silence. Then one day when I visited him and happened to mention that Dr. Haber—discoverer of atmospheric nitrogen fixation—would soon arrive in Japan, he unexpectedly declared with sudden cheer, “Very well—today I shall recount the full story of the artificial heart invention you’ve so long desired to hear,” and began his tale.

Let me pause here for a moment—I am a journalist for S Newspaper’s Academic/Cultural Section. ...Artificial amoebas and artificial hearts were devised to prove that biological movements—whether those of amoebae or hearts—are by no means special or so-called divine or mystical phenomena, but rather things that can be entirely explained mechanically through inorganic materials mimicking their motions. You may not have observed an amoeba’s movements under a microscope, but an amoeba is an organism composed of a single cell—consisting of semi-fluid protoplasm and a nucleus—where the protoplasm alters its shape in various ways to ingest food or change position. When observing its crawling movements, at times it appears like a slug advancing along a fence, and at other times as if the nose of a long-nosed goblin mask were gradually elongating. Now, if one places 20% nitric acid into a flat-bottomed glass dish, drips a mercury droplet into it, and immerses a potassium dichromate crystal at one end of the dish, the crystal gradually dissolves and diffuses along the dish’s base. When it contacts the central mercury droplet, that droplet begins moving as though alive—appearing in such a state that one might think it a silver spider extending and retracting its legs. “This is the artificial amoeba. If one observes closely, the mercury performs movements identical to those of an amoeba.”

“Next, the artificial heart. Needless to say, the heart rhythmically alternates between two movements—contraction and expansion. This rhythmic motion can also be skillfully replicated using mercury. To elaborate: if one places ten percent sulfuric acid into a watch glass, adds a minute quantity of potassium dichromate, inserts a mercury droplet into the mixture, then lightly touches the droplet’s surface with an iron needle—the droplet will immediately begin moving like a frog’s heart, rapidly performing rhythmic contractions and expansions comparable to systole and diastole.”

“Now, to explain why the mercury droplet exhibits such lifelike movements: all liquids exhibit a type of force at their interface with foreign substances, which is commonly referred to as surface tension. Within a liquid’s interior, all molecules are pulled equally from all directions—above, below, left, right, front, and back—but on the liquid’s surface, the molecules there are pulled from the inner side by the liquid’s molecules and from the outer side by the molecules of the substance they are in contact with. When oil is dripped onto water, it spreads across the surface because water’s surface tension is greater than that of oil. Similarly, when mercury is dripped into water, it assumes a spherical shape because mercury’s surface tension exceeds that of water. Now, if one were to temporarily strengthen the surface tension of water contacting mercury beyond mercury’s own tension, or conversely reduce mercury’s tension, the weaker portion would contract less than the stronger part, deforming the mercury droplet. In the case of the aforementioned artificial amoeba, when potassium dichromate contacts mercury within a nitric acid solution, a substance called mercury chromate forms at that site, weakening mercury’s surface tension. Consequently, the mercury’s shape changes; however, since mercury chromate readily dissolves in nitric acid, the surface tension restores itself. Naturally, the mercury’s shape then returns to its original form—to an observer, this appears as a single distinct movement. As potassium dichromate and mercury make contact again in the next instant, repeating this process endlessly, the mercury performs ceaseless amoeba-like motions.”

Now, to explain how the phenomenon of the artificial heart occurs: when an iron needle is brought into contact with mercury in a sulfuric acid solution, contact electricity arises due to the acidic liquid’s presence, and this electricity flows through both the metal and the liquid. At that point, electrolysis of the liquid occurs, and the decomposition product—hydrogen ions carrying a positive charge—adhere to the surface of the mercury, which carries a negative charge. Then the surface tension of the mercury increases, causing the mercury to contract. “When it contracts, it breaks contact with the iron needle and swells back to its original size; when it swells, it touches the needle again, generating electricity that causes it to shrink once more. In this way, it rhythmically repeats the same motion—to an external observer, appearing precisely like the movement of a heart.”

II You must find this lengthy explanation rather tedious, but as my motivation for conceiving the artificial heart lies here, I have thus elaborated in detail upon both the artificial amoeba and artificial heart. “However, of course, the artificial heart I sought to invent was fundamentally different from the artificial heart I have just described.” “I shall elaborate on that matter in due course. Now, in General Physiology, we were repeatedly instilled with the principle that all life phenomena—no matter how complex—could be explained purely mechanically, just as with the aforementioned Artificial Amoeba and Artificial Heart.” "And thus, the idea that there was no need to posit the existence of any mysterious forces to explain life phenomena—that they could be sufficiently accounted for by the powers of physics and chemistry—was deeply ingrained in my mind." Now, upon reflection, even if mercury performed movements resembling those of an amoeba, mercury remains after all mercury—not an amoeba—and likewise, mercury cannot be a heart either. Yet in youth, one finds compromise difficult in all matters, and thus I became what is called an extreme adherent of the mechanistic theory.

"The Mechanistic Theory, as I have just explained, is a doctrine that attempts to account for all life phenomena through purely mechanical explanations. Opposing this, what is called Vitalism asserts that life phenomena cannot be explained without invoking a kind of unfathomable force—one utterly beyond measurement by physics or chemistry. This Mechanistic Theory and Vitalism have, since ancient times, been subjects of debate among scholars—sometimes the Mechanistic Theory prevails, sometimes Vitalism prevails, trading victories back and forth—and even now the dispute continues."

If I were to attempt an overview of its history, we can say with certainty that in primitive times, people undoubtedly believed life was sustained by a kind of mystical force. After all, people of that era could perceive things but were incapable of deep thought; thus when encountering phenomena like life and death, it was only natural they would think these were governed by spirits. However, as knowledge gradually developed, people began to particularly contemplate what life truly was. I must clarify that the development of scientific thought in Japan is quite recent, and as it is difficult to ascertain past intellectual conditions, I shall here use Western examples to illustrate my points. Now, it was the Greeks who conducted relatively deep studies on life, approximately 2,700 to 2,800 years ago. In that era, natural philosophers emerged in Greece who contemplated the creation of the universe and humanity, attributed the origin of all things to the four elements of earth, water, fire, and wind, and established what is called the mechanistic theory—positing that all phenomena are formed through the separation and union of these four elements.

However, later in that same Greece, figures such as Plato and Aristotle emerged. Through their profound studies of human beings, they clearly distinguished mind from body, elevating the mind above the body. This led to the revival of vitalism, as mental phenomena could not be explained mechanically. And with the rise of Christianity, this vitalism took on religious overtones and held sway over people’s minds for nearly a thousand years.

Then came the sixteenth century—the so-called Renaissance period—which saw the emergence of pioneers who would shape modern science. As anatomical and physiological studies of the human body advanced, mechanistic theory regained dominance, giving rise to extreme schools like the iatrophysical and iatrochemical schools that sought to explain all life phenomena solely through physics and chemistry. Yet when the great physiologist Haller appeared at the end of the eighteenth century—identifying phenomena unique to living organisms absent in inanimate matter—and began advocating vitalism, the eminent philosopher Casto coincidentally emerged to champion this cause. Thus vitalism reached its zenith in the first half of the nineteenth century.

Then again, in the latter half of the nineteenth century, natural sciences achieved astonishing development: Darwin’s renowned theory of evolution and the cell theory emerged, and mechanistic theory was revived to persist into the present day. However, even the great physiologist Du Bois-Reymond—who passed away some years prior—leaned more toward vitalism. Thus, throughout various eras, vitalism and mechanistic theory alternated victories. Yet even a single scholar who adhered to mechanistic theory during one period might convert to vitalism due to some motive. “Indeed, from my student days until I completed the invention of the artificial heart, I had been an extreme proponent of mechanistic theory—but upon finally applying it in practice, I abandoned that theory.” “And at that same moment, I cast aside my research on artificial hearts.”

III Now, having attended lectures on artificial amoebas and artificial hearts and become a devotee of the mechanistic theory, when I reached my second year and came to perform practical exercises with artificial amoebas and artificial hearts, I suddenly wondered: Could one not artificially construct a heart—whether human or animal—to serve as a substitute for the original? When I attended lectures on physiological specialties, I learned that the heart merely serves as a kind of pump. Yet despite its function being so simple, there is no organ as vital as the heart. While the heart is beating, even if one has fallen unconscious, that person cannot be said to be dead. Therefore, I thought that if—when the heart stopped—one were to immediately replace it with an artificial heart, supply energy from an external source to activate the pump’s function, and send blood throughout the body, it would be possible to revive even those who had died—and depending on the circumstances, perhaps even grant them eternal life. The artificial heart was completed through an extremely simple principle: receiving blood from the vena cava that had circulated throughout the body into the pump, then sending this via a valve into the aorta. Since one could use an electric motor to operate the valve—as long as Earth’s magnetism existed—the electricity supply would never cease; thus humans equipped with artificial hearts would achieve longevity for as long as the Earth endured… I even indulged in such fantasies back then.

What made me yearn for the artificial heart was the extremely intricate theories concerning the heart. While meticulous attention to detail lies at the core of scholarship, I found it rather burdensome during my student days to be subjected to such a multitude of theories. Though listening to academic debates could prove fascinating on occasion, their cumulative weight became intolerable. I came to think that physiology might better be described as an aggregate of theories, and that streamlining them would not only benefit students of physiology but could ultimately simplify life itself.

As you may know, there are two theories regarding the origin of cardiac motion. One is called the muscle theory, which posits that the heart moves due to the excitation of the muscles forming it; the other is the theory that it moves due to the excitation of nerves entering those muscles. The heart continues to beat without issue even when excised from the body, provided appropriate methods are employed; thus, there is no doubt that the force driving its motion originates from the heart itself. However, whether this force arises from its muscles or from the nerves within remains undetermined. To discover which of these was correct, numerous scholars conducted extensive research on the hearts of various animals—there were even those who dedicated their entire precious lives to this research—and yet no satisfactory resolution was reached. A certain scholar conducted research on the heart of a rare animal such as the horseshoe crab—one seldom encountered—and supposedly fully substantiated the nerve theory, boasting greatly of this achievement; however, scholars, prone as they were to narrow-minded dispositions, did not easily come to accept it.

That was when I came to think. “Whether muscle theory or nerve theory—they only exist because we have this thing called a heart. Troublesome theories sprout from troublesome organs.” “Once the artificial heart is realized, both muscle theory and nerve theory will be smashed to splinters.” “The electricity powering the motor would become their true origin—all previous theories unified under a single ‘electrical theory.’” “And against this electrical theory, no one could voice opposition.” “What glorious simplicity!” “Though I called it youthful excess, I’d become intoxicated by this supremely straightforward notion.” Yet upon deeper reflection—had God crafted our bodies—how much more absurd than my electrical fantasy must our squabbling over muscle theories and nerve theories appear through divine eyes? In any case, overwhelmed by the mental clutter of competing doctrines, I resolved to complete my artificial heart invention the very day I graduated university.

IV When I became a third-year student and began attending clinical lectures while directly handling patients, I came to keenly feel modern medicine’s impotence while simultaneously discovering that what we studied as medicine was ultimately nothing more than an accumulation of theories—something far removed from practical application. “If theories were definitively settled one way or another, treatments could be administered with clarity,” I explained. “But given these theories remain mired in debate, interventions inevitably become half-measures.” “Among countless diseases,” I continued, “those treatable with specific pharmaceuticals number fewer than fingers on one hand—for the rest, we merely administer placebos and wait for nature’s cure.” My voice grew sharper. “And when lives hang in the balance? As you know, every case ends the same—camphor injections administered without exception.” “In Japan alone,” I noted bitterly, “over a million perish yearly, most crossing to the afterlife with camphor as their parting gift.” Leaning forward, I tapped the table for emphasis. “This camphor—a cardiac stimulant strengthening heart function—reveals medicine’s ultimate aim: fortifying that vital pump.” “Whether acute or chronic,” my tone turned didactic, “if hearts maintain undiminished strength, curable diseases resolve themselves while incurable ones merely persist without claiming lives.” “Even plague and cholera,” I declared, “ultimately kill through cardiac assault! Thus scholars must abandon pathogen studies—forge hearts of iron instead! No—” My fist struck wood— “advance further! Devote ingenuity to crafting steel artificial hearts!” “Then,” my hands spread wide, “no need exists to catalog individual maladies or amass treatises.” “Complete the artificial heart,” I whispered fiercely, “and no disease warrants fear.” Pausing, I gazed beyond my listener. “Each reflection on Pasteur’s vaccines, Koch’s postulates, Ehrlich’s chemotherapy—” My throat tightened— “while grateful for their gifts, I lamented bitterly: Why hadn’t such geniuses pursued cardiac engineering?” “History brims with medical titans,” I mused, “but had they united on this single purpose? An ideal device would’ve emerged long ago—utopia itself constructed through circulatory perfection.” My chair creaked as I straightened. “Humanity’s fatal flaw through cultural evolution? Rendering simple truths needlessly complex.” “Like architects reveling in maze-wrought torment,” my laugh held no mirth, “we’ve made suffering our diversion.” “Complexity breeds distraction—” My finger traced circles in air— “trivialities eclipse fundamentals.” “Thus Rousseau’s cry—” My voice dropped an octave— “‘Return to nature!’” “Not regression,” I clarified sharply, “but shedding superfluities to reclaim essence.” “This truth burned—” My palm pressed over sternum— “Complete the artificial heart! Restore medicine’s foundation! Thus resolved—” Eyes blazing— “my spirit surged like mercury through charged electrodes.”

The advancement of human culture, the increasing complexity of things, and medicine’s focus on peripheral issues gave rise here to a dreadful kind of disease. That needless to say was tuberculosis. Tuberculosis did not readily arise from the tubercle bacillus alone; it occurred when the human constitution became conducive to the proliferation of the bacillus—and since this susceptibility was itself born from humanity’s cultural development—tuberculosis could ultimately be seen as divine irony directed at human civilization. As proof of this modern medicine held no authority over tuberculosis. Far from holding authority it merely looked on helplessly at its raging spectacle. “To doctors this might have been their rice bowl—but patients found nothing but torment.”

Therefore, all who aspire to medicine turn their thoughts to the treatment of tuberculosis. I was indeed one of them, but I learned that this problem too would be immediately resolved by the invention of the artificial heart. As I stated earlier that the solution to all disease treatments would be achieved through the artificial heart, tuberculosis naturally falls within that scope—but since the organ known as the lungs holds a unique relationship with the artificial heart, I wish to address it specifically here.

The primary function of the lungs was needless to say the gas exchange of blood. In other words, venous blood—which had circulated throughout the body containing carbon dioxide—would be sent from the heart to the lungs, where it would discard its carbon dioxide, take in oxygen from external air to become arterial blood, return to the heart, and then be sent throughout the body. Therefore, were one to create an artificial heart while attaching a device that absorbed or expelled carbon dioxide from venous blood while supplying oxygen, the lungs would become entirely superfluous. “If implemented,” he continued, “no matter how severely tuberculosis might ravage the lungs themselves, they’d feel no discomfort whatsoever.” “Consequently,” he concluded with clinical precision, “the tuberculosis problem would resolve itself immediately.” “Moreover,” he added, leaning forward slightly, “by pre-attaching what might be termed an artificial lung to the artificial heart beforehand, the surgical implantation procedure becomes remarkably simplified—truly achieving two objectives with a single intervention.”

However, when one attached an artificial lung to the artificial heart and freed the lungs from gas exchange duties, I believed a certain remarkable phenomenon would occur in that scenario. To explain what that phenomenon was: if lung cells were liberated from gas exchange duties, it would likely enable humans to drastically reduce their food consumption. Therefore, I imagined that the artificial heart would not only save humanity from the anguish of disease but, depending on circumstances, also rescue them from food scarcity—enabling all people to live on mist like so-called Taoist immortals.

Regarding the invention of the artificial heart, there may have been scholars who had given it some consideration before me; however, I believed I was likely the first to conceive that liberating the lungs from their gas exchange function could significantly reduce food consumption. For this reason, I decided to say a few words about it.

V

For some time, I had harbored doubts regarding the presence of such a vast quantity of nitrogen in the air. Indeed, nitrogen occupies four-fifths of the entire volume of air—yet it was considered to hold no benefit whatsoever for human survival. Interpreting all things teleologically may be dangerous—but I believed this atmospheric nitrogen must surely benefit human survival like oxygen does. The oxygen in this same air remains indispensable for survival even momentarily; yet nitrogen—fourfold in quantity—meaninglessly circulated through human bodies without purpose—an irreconcilable contradiction by any measure. Therefore I concluded: nitrogen’s passage through us held meaning. What seemed meaningless was merely humanity’s failure to recognize nitrogen’s value.

"As you know, the chemical substance constituting the most vital tissues of the human body is protein." "Since this protein is a nitrogen-centered compound, nitrogen compounds are something the human body cannot do without even for a day." "While we normally take in these nitrogen compounds through food, I considered it a grave oversight by God that nitrogen in gaseous form remained entirely unused by the human body despite nitrogen in compound form being indispensable." "And at the same time, I came to interpret that this was by no means an oversight on God's part—that He had properly prepared free nitrogen to be utilizable, but humans had simply failed to notice it." "Now, the term 'God' may not be to your liking, but I believe it's more straightforward than saying 'the Creator' or similar terms, so please bear with me."

“Now then, in which organ of the human body did God bestow the function to utilize free nitrogen?” “It goes without saying that it must be the lungs through which nitrogen constantly passes in and out.” “While the skin—through what is termed ‘skin respiration’—may engage in oxygen utilization and perhaps nitrogen utilization to some extent, I considered that just as oxygen utilization occurs primarily in the lungs, nitrogen utilization too should principally take place in the lungs.”

“Are you aware that a type of bacteria residing in the soil possesses the ability to fix atmospheric nitrogen—that is, to convert free nitrogen into nitrogen compounds?” “If even the lowest organisms like bacteria have been endowed with such a wondrous power, then how much more certain must it be that the cells of humans—the highest animals—possess this same power?” “And so, I inferred that it was precisely in the lung cells that a nitrogen-fixing function—like that of soil bacteria—was endowed.”

However, because lung cells have the crucial role of gas exchange, they naturally cannot attend to nitrogen fixation. “Furthermore, since the nitrogen compounds necessary for human survival are replenished through food, the lung cells do not necessarily need to work.” “However, if one were to cease food intake and enter a so-called state of starvation now, the lung’s nitrogen fixation function would certainly become active.” In other words, instead of the digestive tract, the lungs would take charge of the body’s nutrition. The fact that one can survive for weeks during starvation fasting by drinking nothing but water must certainly be because the lungs are fixing nitrogen. When conducting starvation voluntarily, the reason experimenters can prolong their fasting the more they remain at rest is most appropriately interpreted as follows: by reducing gas exchange work through rest, conversely, the nitrogen fixation function becomes vigorous. Moreover, when considering tuberculosis cases, the reason patients become markedly emaciated and must replenish proteins in large quantities should be attributed to the fact that the lungs, having been compromised by the tubercle bacillus, have their nitrogen fixation function weakened.

Therefore, if the lungs were to be relieved of gas exchange duties, they would undoubtedly devote their full capacity to nitrogen fixation. And if human nutrition were to be supplemented through that nitrogen fixation, then perhaps there would no longer be any need to ingest protein as food through the mouth. Some have calculated that the human body requires only two grams of protein per kilogram of body weight per day, but I believed that if all lung cells were to engage in nitrogen fixation, they could easily produce that amount of nutrients. Therefore, if one were to complete the invention of the artificial heart and substitute the gas exchange function of the lungs with an artificial lung attached to it, humans could greatly reduce their food consumption; moreover, if research were to advance further, humans might even be able to live without food. …and so I fantasized about such things back then, thinking I wanted to graduate from university as soon as possible and devote myself to inventing the artificial heart.

VI

Upon finally graduating from university, I was permitted to join the physiology department and, with authorization from the head professor, commenced research on the artificial heart. Due to personal circumstances, I had married while still enrolled in university, but begrudging the time spent commuting from home, I secured permission from the head professor for my wife and me to lodge in a room within the department. My wife developed a keen interest in my research and became my assistant. We labored from dawn until deep into the night. Though located within the city proper, nights across the university's expansive grounds fell profoundly silent—the gaslight reflecting in our high-ceilinged laboratory evoked an indefinable loneliness, yet whenever we exchanged smiles across an experimental animal with eyes shining in hope, we would immerse ourselves in immeasurable joy. When experiments faltered, I often worked through the night wearing a grim expression; during such times my wife too would stay awake till morning, tirelessly striving to uplift my spirits. Through countless repeated failures—when I teetered on the brink of despair—it was always my wife who rescued and encouraged me. Had my wife not been there, I could never have brought the artificial heart's invention to completion. That very wife now walks among the living. And through that wife's death, I was compelled to abandon this hard-won invention I had finally perfected.

“What a strange fate this is.” When I think of the hardships and joys of those days, I still feel my heart race. Ah, I’ve unwittingly digressed from the main subject. Now, when I actually began working on inventing the artificial heart, I realized its completion was nowhere near as straightforward as I had imagined during my student days. And so I came to think that while there may have been those who conceived of inventing an artificial heart before me, the lack of any records in the literature was likely due to their inability to realize it.

In ordinary physiological experiments, it was considered standard practice to first conduct them on readily available frogs, but for artificial heart experiments, frogs proved far too small for intricate work, so I resolved to perform the tests on rabbits. "Oh, how many rabbits I must have killed." All procedures were always performed under anesthesia, but however noble the experiment’s purpose of saving humanity might have been, I now find myself filled with remorse toward those rabbits. "The public often misunderstands scientists as heartless beings—some even think we possess such brutality as to take pleasure in killing experimental animals—but not all researchers fit that mold." The reason I nearly abandoned my experiments multiple times midway was precisely because I could not endure causing those rabbits pain.

The procedure of the experiment was as follows: first, we would place a rabbit on its back, secure it to a special platform, administer anesthesia, open the cardiac region of its thorax, then incise the pericardium, after which we would attach the pump we had devised in place of the heart. “To put it that way makes it sound quite simple,” he said, “but in reality, the surgery was by no means easy.” At first, we attempted to excise the rabbit’s heart and replace it with a pump, but this resulted in such severe hemorrhaging that achieving our objective proved utterly impossible. Consequently, we later opted to leave the rabbit’s heart intact while affixing relatively long tubes to the pump and connecting them to appropriate major blood vessels instead.

Initially, I did not devise an artificial lung and focused solely on researching the artificial heart. However, with only the artificial heart, connecting the pump’s tubes to both the pulmonary artery and pulmonary vein actually required more effort, so I realized it would be more practical to design an artificial heart equipped with an artificial lung. The heart, as you know, consists of four chambers, so naturally we had to create four chambers in the artificial heart—that is, the pump. However, with an artificial heart equipped with an artificial lung, only two chambers—or effectively one chamber—around the valve were necessary, making it remarkably simple.

For the pump material, we initially used thick-walled glass, and for the valves, hard rubber. This was to observe blood flow patterns externally, but later we switched both pump and valve entirely to steel. And through experience, we found that steel was more suitable than glass for the artificial heart.

“Now I must explain the pump’s structure—but first let me describe the artificial lung’s principle.” “The principle itself was simple enough: remove carbon dioxide from venous blood arriving through both vena cavae, replace it with oxygen, then send it into the aorta.” “However while oxygen supply merely required connecting an oxygen tube，carbon dioxide removal proved far more troublesome.” “The difficulty lay not in removal itself，but in eliminating massive quantities instantaneously.” “Collecting venous blood in a fixed container and applying strong negative pressure could remove some CO₂，but extracting all gas from rapidly flowing blood remained extremely challenging.” “After extensive deliberation，I concluded reducing overall venous CO₂ levels might overcome this obstacle.” “By circulating oxygen-rich blood faster than normal—tripling or quadrupling valve actuation frequency—I successfully minimized venous CO₂，resolving artificial lung issues with relative ease.”

Thus, the carbon dioxide removal section of the artificial lung was directly connected to the vena cava; the blood stripped of carbon dioxide entered the artificial heart—that is, the pump—advanced through a valve-equipped aperture, was pushed out by the valve, received oxygen supplied through an installed tube there, became what we call arterial blood, and proceeded into the aorta. “Now, you might think an artificial heart equipped with an artificial lung would be quite bulky,” he continued, “but through gradual refinements and improvements, we reduced its size to approximately one and a half times that of an experimental animal’s original heart.” “By using steel as material,” he added, “we could minimize the artificial heart’s volume.” “I neglected to mention earlier,” he concluded, “that an electric motor powered the valve’s movement—and we later employed electrical power to generate negative pressure for carbon dioxide removal too.”

When I explain it this way, it may appear that we proceeded with the experiments quite simply—yet the process of devising and refining them up to this point was anything but easy. Both my wife and I worked so absorbed that we literally forgot to eat or sleep on numerous occasions. Even once completed, connecting the machine to a rabbit’s vena cava and aorta proved most formidable. Initially, we directly connected steel pipes to blood vessels using catgut thread, but steel’s rigidity later compelled us to insert rubber tubes of fixed hardness between them. Yet even then, uneven pressure regulation would frequently cause joints to part—bleeding out rabbits in moments.

A phenomenon that should be considered particularly unpleasant in surgery was the coagulation of blood. As you know, blood coagulates immediately upon exiting blood vessels, but even a single fragment of this coagulum, if reintroduced into the bloodstream, would cause embolisms in small vessels and lead tissues to necrosis; thus there remained no alternative but to devise means of preventing blood coagulation. Therefore, I decided to use a substance called hirudin, taken from the mouthparts of frogs, to prevent coagulation and perform the surgery. However, even when the surgery was completed without incident, blood clots would readily form on the inner side of the contact points between the major blood vessels and rubber tubes, and we still experienced repeated failures. Through experience, we found that if we moved the valve more quickly, coagulation would not occur. With the completion of the artificial lung’s design, we were able to overcome this critical challenge.

Next among the phenomena that should be considered unpleasant was suppuration caused by bacteria. However, if we carefully sterilized the instruments and performed so-called aseptic surgery, rabbit blood possessed relatively strong bactericidal power to avoid suppuration—but above all else, the most crucial factor in preventing suppuration was performing the surgery swiftly. Not only to prevent suppuration but also to eliminate all other unpleasant phenomena, performing the surgery in as short a time as possible remained the most crucial condition. Fortunately, due to having sacrificed numerous rabbits, I eventually became able to perform the entire surgery in a mere ten minutes. Though it was merely a procedure of opening the thorax to attach the artificial heart and then closing it again, I felt somewhat proud at having managed this in ten minutes. Needless to say, the artificial heart remained located outside the thorax. It would have been ideal if we could have housed it within the thoracic cavity, but with the device configuration I described earlier, we could not possibly have achieved that. "You may well think a steel heart would require periodic oiling," I added, "but fortunately, since blood contains some fat, there was no need for such concern."

Now, I believe you can well imagine how immense our joy was when the invention of the artificial heart was finally completed. When we saw the rabbit—still bound to the platform, surviving nonchalantly for five hours, then ten hours after awakening from anesthesia—as the electric motor rotated with a sound like the buzzing of a horsefly madly darting among leaves on a mild autumn day, its valves operating at blinding speed, we clung to one another and choked back tears of joy. The sounds—beginning with the motor’s hum, followed by those of carbon dioxide removal and oxygen supply—might have been unpleasant for the rabbit itself, but I thought that if it had consciousness, it would surely share in our joy at having broken through artificial heart research’s first great barrier, a challenge no one had overcome since humanity’s dawn. Moreover, I thought that if we could advance our research further and succeed in restoring life by installing artificial hearts into once-dead bodies, then even the rabbits would surely feel gratitude from their very core. And since we had overcome the first critical obstacle, this second one should have been relatively easy to surmount. Thus we soon began research on this next phase, but there arose an entirely unforeseen impediment.

VII "They say 'no good deed goes unpunished,' and truly, nothing goes as one wishes." One night about a week after I had broken through the first critical obstacle, I suddenly coughed up blood.

The first stage of artificial heart research was completed approximately a year and a half after I entered the physiology department, but from about half a year prior to that, I had begun to occasionally experience a slight cough. I likely had some degree of fever during that period, but being utterly absorbed in my research with no time to spare for such concerns, my physical overexertion must have taken its toll. Ultimately, I was struck by hemoptysis and was forced to temporarily halt my research. Perhaps it was the recklessness of youth—not conducting research with a composed attitude and persistently rushing forward that was my downfall. Now that I have fortunately regained my health, I came to realize that the more significant the endeavor, the more deliberately one must advance the research henceforth.

When I coughed up blood, the Chief Professor strongly recommended hospitalization for treatment, but I simply could not bring myself to leave the vicinity of the laboratory. We converted our lodging room into a sickroom as it was, and my wife became a nurse and cared for me. Initially, I coughed up approximately ten grams of blood, so I immediately lay down on the bed. When I had a friend working in internal medicine come examine me, he administered a hemostatic agent and advised absolute rest, so I lay on my back and remained still.

Suddenly awakening at midnight, I felt an itching, tickling sensation in my chest. The moment I became aware, a harsh cough erupted the next instant, and still-warm blood surged violently into my mouth. Cough after cough—my wife brought a cup, but before my eyes it filled completely with crimson. My startled wife brought a basin to catch the flow. I kept coughing while lying on my left side, but excess blood forced its way through my nasal cavity too, coating the lower half of my face in sticky red. My chest made a sound like stabbing a beehive—then immediately rumbled like thunder. The basin filled halfway in moments, making me fear I might cough out every drop of blood in my body. On the white sheets bloomed red-black stains of varying sizes, while my wife’s hands supporting the basin shook uncontrollably.

The gas lamp hissed; the night fell deathly silent. As I coughed up blood, I was overcome by a profound sense of solemnity.

However, fortunately, the hemoptysis subsided. The sensation that followed the cessation of hemoptysis defies easy description. My mind momentarily became perfectly clear. However, after a while, I began to feel dazed. But that too was fleeting, and then a fierce anxiety assailed me.

It was terror. An unbearable terror. From the moment I was born until then, I had never known such terror. Needless to say, it was terror born from the certainty that hemoptysis would soon begin anew. This might still be called the terror of 'death'. Yet somehow, I felt this terror surpassed death itself. Because of this, I could no longer sleep. The terror kept me awake. The conviction that sleeping would inevitably restart the bleeding left me rigidly alert through the nights. The ruptured vessels in my lungs defied external intervention. Doctors could only watch silently - hemostatic agents proved utterly useless. To abandon ruptured vessels untreated... What consummate horror! Until that moment, I'd never considered patients' terror while examining them. There I first understood - physicians untouched by illness themselves lack qualification to treat patients. I reached this conclusion: remove the terror accompanying hemoptysis, and the bleeding itself becomes trivial. Thus I apprehended medicine's true purpose - not curing disease itself, but excising the terror of illness.

To dispel my sleepless anxiety, I had my wife administer a morphine injection. Convinced a standard dose couldn't alleviate this terror, I asked her to inject a slightly larger quantity. And what do you suppose occurred? Within less than an hour, that dreadful anxiety had entirely dissipated. Before I realized it, I found myself wandering through pleasant dreamscapes. "Have you ever taken morphine?" "Or read that volume called *Confessions of an Opium-Eater*?" "When one takes morphine, you're pulled into a peculiar realm where dream and reality blur." "That world contains no trace of terror." "It's a pleasure garden transcending time and space."

When I abruptly became aware, there was a sound like a droning horsefly near my ear. When I wondered what it was and listened closely, there came a whooshing, gushing sound like rushing water. I thought I was strolling through ×× Park with my wife, listening to a waterfall’s roar while basking in the autumn sun to my heart’s content—but upon closer reflection, I lay in bed. Realizing this, I looked beside me and saw the motor whirring incessantly, the negative pressure generator and oxygen supply device humming into action.

Artificial Heart! That’s right—I had the Artificial Heart installed. The Artificial Heart’s comfort! The Artificial Heart that knows no terror! The Artificial Heart alone completely eliminates the terror of illness! The Artificial Heart alone allows people to revel in paradise! What a peaceful world this was!

The moment I realized, a raucous cough erupted and once again the hemoptysis began. Paradise suddenly transformed into the depths of hell. What I had mistaken for the artificial heart's motor was nothing more than abdominal sounds caused by hemoptysis. I had merely been made to misrecognize those sounds through morphine's effect as a peaceful world arising from the artificial heart. The hemoptysis stopped after about three cupfuls, but terror violently assailed me once more. That is, because the effect of morphine had vanished.

Lying still on my back, I found myself profoundly yearning for the Artificial Heart. I came to consider that the Artificial Heart, just as I had envisioned it in my dream, must undoubtedly save one from the “terror of disease.” The reason I had conceived the invention of the artificial heart was to save humans from death and achieve longevity and life extension, but after experiencing the terror of hemoptysis that surpassed even the fear of death, I came to believe that even if only to save one from the “terror of disease,” I had to complete the artificial heart.

At that moment, I particularly recalled Lange’s theory I had heard long ago in psychology lectures. “To give an example,” I explained, “Lange’s theory claims we feel terror because we make the various expressions that occur during terror.” In simpler terms—that one doesn’t feel terror because their hair stands on end and face turns pale; rather, one feels terror because their hair stands on end and face turns pale—it was what you might call an extreme mechanistic theory. Even while coughing blood, I—who still clung solely to mechanistic doctrine—discovered this theory could elegantly explain why terror would disappear through the Artificial Heart. That is to say, during terror the heartbeat slows and in severe cases stops. “This means nothing more than that the slowing or stopping of the heartbeat causes terror itself.” Therefore, if an Artificial Heart were installed and made to beat unvaryingly, the sensation of terror could never arise.

Thinking this way, I wanted to recover as soon as possible and begin the second stage of research on the artificial heart. Fortunately, the hemoptysis stopped after five episodes, and the subsequent progress proceeded smoothly. After about a month and a half of convalescence, I was able to get up again and return to work. The friend who had been treating me persistently recommended a change of climate for recovery, but I stubbornly refused. My wife—sympathizing with my resolve—and I once again embarked on our research into the artificial heart. "If only I had heeded my friend’s advice back then," I now think with utmost regret. The change of climate for recovery was necessary more for my wife than for me. It seems my wife had already suffered considerable damage to her lungs by the time she was nursing me, but being as stubborn as I was, she never showed the slightest sign of it to me.

VIII

"The second stage of artificial heart research—that is,the research on reviving once-deceased animals through artificial hearts—was not as difficult as I had expected." "I administered various poisons to kill rabbits; waited for their hearts' final beats; immediately opened their chest cavities; conducted experiments by attaching artificial hearts; through this discovered procedures begun within five minutes post-mortem could restore consciousness." "However,beyond five minutes proved impossible." "Reviving cold corpses remained beyond hope." "When first reviving dead rabbits effortlessly despite anticlimax we ran through lab elated." "Verbal simplicity belied extensive rabbit sacrifices." "Selecting suitable poisons posed particular difficulty." "'We couldn't await natural death requiring artificial termination,but blood-altering toxins complicated matters.'" "Moreover,single-poison success didn't guarantee others' efficacy necessitating exhaustive trials—efforts proved monumental."

Since the original purpose of the Artificial Heart was to save humanity from terror, once we succeeded with rabbits, it became necessary to apply this to humans.—I stated earlier that saving humanity from terror was the purpose, but after experiencing hemoptysis, I had no time to consider other matters—I came to think that if we could save humanity from terror, we could form a paradise. A world without terror! What a blissful world that would be!—And so, as the next step, we decided to test the artificial heart on dogs larger than rabbits. For dogs, we simply needed to use a larger pump; there was nothing different about the surgery itself except requiring slightly more electricity than with rabbits. Of course with dogs, we only attempted experiments to revive them after death; through this we learned that starting within ten minutes postmortem achieved our objective. In other words, we found that larger animals permitted somewhat delayed attachment of the artificial heart. I considered this difference likely stemmed from variations in blood coagulability. The smaller the animal, the faster its blood coagulates. Needless to say blood coagulates after death—once solidified, the artificial heart becomes useless. Proceeding under this hypothesis, I selected a sheep matching human weight for experimentation and indeed succeeded in revival even when starting fifteen minutes postmortem. This time it meant humans. To think how desperately I wanted human trials—what cruel irony fate delivered. The first person I tested the artificial heart on was my wife Fusako—she who had helped invent it.

One day, my wife suddenly collapsed in the laboratory. I immediately lifted her and moved her onto the bed. When I gave her red sake, she soon regained consciousness, but upon touching her forehead—burning like fire—I applied the thermometer and was shocked to find a high fever of 41.5 degrees. I immediately prepared an ice bag and cooled her, then had that internist friend come over. The feeling I had when hearing the diagnosis from my friend still makes me shudder to this day. "That is," my friend declared, "a full-fledged case of miliary tuberculosis." "Miliary tuberculosis!" It was no different from a death sentence. My wife had long been afflicted with a lung condition, and through enduring it again and again, she had finally fallen into an irreversible fate. I sank into immense sorrow, yet somehow I also felt there was a glimmer of hope there— Needless to say, it was the hope that I could save my wife through the artificial heart.

My wife, upon seeing the expressions on my and the friend’s faces and apparently having already perceived her own fate, no sooner had the friend left than

“I won’t recover, will I?”

she asked.

I found myself at a loss for words and silently shook my head. “I understand perfectly well.” “But I am not the least bit afraid of dying.”

Her voice was so filled with hope that I inadvertently, “Huh?” I said as I stared at her face. “There’s the artificial heart, after all. Listen, when I die, please attach it right away. I’ll surely come back to life.” “Wouldn’t saying such things make me sad? You must stay strong.” “You’re the one who needs to stay strong. After all the effort we’ve put into conducting so many experiments up to now, if we don’t test it on humans, it’ll all be for nothing. When we succeeded with rabbits, I resolved that even if I didn’t fall ill, I would intentionally die and have you conduct the experiment on my body.”

I involuntarily grasped her hand and kissed her lips. “So, will you conduct the experiment?” “Ah, does that please you?” “Until now, with only rabbits and dogs tested, no one could have described what survival through an artificial heart truly feels like.” “That’s precisely what I wish to experience myself.” “I firmly believe that a tranquil world—just as you envision—will be realized.” “Thinking of that makes me almost eager to die.” “Tell me—when do you suppose I’ll die?”

I grew increasingly sorrowful.

“Oh, it’s alright…”

“That’s not good.” “I’ll be devastated if we miss the window—please make the preparations quickly!”

That's it! If she truly couldn't be saved, then fulfilling my wife's wish through the artificial heart would be an act of kindness toward her! Thinking this, I found time amidst nursing to prepare the artificial heart. Usually, since I did it together with my wife, my heart would swell with courage, but this time, I somehow felt a dark gloom come over me.

Nine

The morning after completing preparations for the artificial heart, my wife's condition changed dramatically. Friends came rushing over, but my wife kept only the chief professor and the friend serving as her physician behind while sending others away. She then asked them to ensure her husband would face no legal repercussions when he conducted the artificial heart experiment immediately following her death. Tears glistened in the chief professor's eyes.

Then my wife had the two leave the room and requested that I show her the artificial heart. When I picked it up and showed her, my wife smiled sweetly, but at that very moment her throat rattled once, and she quietly closed her eyes.

Snapping back to my senses, I informed the people outside that my wife had stopped breathing, requested that no one enter during the surgery, and quickly began the operation. The sensation when the scalpel touched the chest—that is something I still cannot forget. I swiftly opened the chest cavity and attached the artificial heart. The surgery began nine minutes after her death and concluded in thirteen minutes.

When I turned the switch with my blood-stained hands, the motor started up with its distinctive sound. One minute, two minutes, three minutes—I examined her pulse while staring into her eyes. Since the valve operated at 250 cycles per minute, counting her pulse was impossible, but I could clearly sense the blood circulating safely.

Five minutes! At the same moment her lips regained their color, her eyelids quivered faintly. I nearly cried out in joy before stopping myself. This was exactly how it had begun during my experiments with dogs and sheep—that first delicate tremor beneath closed lids. Seven minutes! Her eyeballs started rotating beneath their thin veils of skin. Clenching my bloodied hands, I swallowed the elation rising in my throat and kept watching. Nine minutes! Her eyes snapped open—wide and vacant—while her lips parted in a soundless twitch.

Eleven minutes! Her gaze focused on my face. Thirteen minutes! She let out a deep sigh: “Ah…” I involuntarily shouted.

“Fusako! Do you understand? You’ve come back to life!” However, she did not smile.

“Fusako! The artificial heart was a success. Aren’t you happy?” “I am happy,” she said mechanically.

“Are you happy? I’m happy too. You’ve gained a new life!” “Oh!” she said, her face still mask-like as ever. “I did say I was happy just now, didn’t I? But I can’t feel happy.” I started. Then I suddenly kissed her.

“Oh, please forgive me!” “I don’t feel the slightest bit of longing.”

I was even more astonished. "You—I'm sorry." "Even if I try to laugh—I can't." "Even if I try to be happy—I can't feel happy." "Living like this amounts to nothing!"

My despair at that moment! I involuntarily buried my face in the bed.

“You!” “No!” “Quickly, please remove the artificial heart.” “Dying or coming back to life—I feel nothing at all!”

Two years of research were shattered into splinters by this single statement. We who had thought only of eliminating fear had failed to notice that the artificial heart would also remove pleasure and other emotions. Remorse! Shame! My wife does not even feel that now. The artificial heart was ultimately nothing more than an artificial human life. *Click!* I resolutely twisted the switch to stop the motor.

“Oh, I’ve gone and rambled on at such length. My bitter experience may perhaps have substantiated Lange’s theory, but ever since then, I have harbored dissatisfaction with what is called the mechanistic theory. The mechanistic theory ultimately crushes human hope. It may be precisely because there is fear, disease, and death that humans find meaning in living.”

Thus, with my wife’s death, I completely severed all ties to my artificial heart research. However, concerning the nitrogen fixation function of the lungs I mentioned earlier, I do intend to resume studying it when the opportunity arises—but since haste leads to blunders, I plan to approach it at a leisurely pace.

“Well, since you mentioned Dr. Haber—the inventor of the nitrogen fixation method—coming to Japan, I ended up recounting my life’s confession of regrets.” “After all, perhaps physiologists find it far more reassuring to be merrily crafting mercury ‘artificial hearts,’ hahahaha.”