Tabibito (The Traveler)

Hideki Yukawa, L M Brown, R Yoshida

• Publisher: WSPC
• Year: 1981
• Print ISBN: 9789971950101
• eBook ISBN: 9789814338004
• Topic: Biological Sciences
• Subtopic: Science General
• Index: Biological Sciences

This is Yukawa's autobiography of his early years, written in Japanese when he was fifty years old. It describes his family background and the education and experience, both social and intellectual, that helped to form his character and direct his career. Especially valuable to the historian of science are his discussions of scientific relationships with his colleague Sin-Itiro Tomonaga, with his teacher Yoshio Nishina, and with his students (who later became his collaborators): Sakata, Taketani, and Kobayashi. The Story ends with the writing of his first scientific paper in English, being the birth of the meson theory of nuclear forces.

Also included are the original paper of the meson theory by Prof H Yukawa and an introduction by Prof L M Brown.

Contents:

• Introduction: Hideki Yukawa and the Meson
• The Home of Knowledge
• My Father
• "Iwan" (I won't Say)
• Somedono
• A Voyage
• The Wave and the Wind
• Episode
• Youth
• The Narrow Gate
• Crystal
• A Turning Point
• Kurakuen
• Epilogue
• Meson Theory by H Yukawa

Chapter 1

The Home of Knowledge

Many people think that Kyoto is my hometown. It is actually the place where I received most of my education. After graduating from the University in Kyoto, I lived for a time in the vicinity of Osaka, but then I returned. When I came back from America in 1957, I did not feel that I was “home” until the train approached Kyoto through the Tōyama tunnel.

But, unquestionably, I was born in Tokyo (at Nibanchi, Ichibei-cho, Azabu). I cannot remember the house of my birth, not even the plum blossoms there. I know them only through my mother, but in my mind I know they are extremely beautiful. (Perhaps my subconscious tries to beautify my birth.)

I lived in my house at Azabu for fourteen months. Then my father, Takuji Ogawa, who was the head of a geology research center in Tokyo, accepted a professorship at Kyoto Imperial University and moved there with his family. He taught the first geography course at Kyoto University.

Azabu was burned during the War and is no longer recognizable as it was. Our house was at the end of a narrow path on a slope. One of our neighbors was Takuma Dan, and Kaneko Yanagi had a large and impressive house there (I am told).

When I was a small boy in Kyoto, I used to beg my mother to tell me about the house and she would begin: “It was not a large house, but it was sunny and comfortable. You were born on a cold day and … .” Of course it was cold, it was the 23rd of January! The plum blossoms must have been still hard buds. My oldest brother, Yoshiki, was six; my second brother, Shigeki, was four. They barely remember the house, but my sisters Kayoko and Taēko, who are older, seem to remember it better. Fifty-year-old memories are probably not very accurate.

After the luggage and parcels were shipped from Tokyo to Kyoto, the family stayed at an inn at Shinbashi, near the railway station. “The train tracks at night emit light, and I still remember the blue glow,” my brother says. We moved in late March; the nights must have been cold.

The year was 1908, not long after the Russo-Japanese War. The atmosphere in the country was probably tense, and the vicinity of Shinbashi Station must have been incredibly dark by modern standards. Under the oil lamp that hung from the low ceiling of the old inn where we stayed, I can imagine how the family members harbored in their hearts the hopes and fears of a new beginning. (But the inn may already have had a dim electric light.)

My own memories begin from the time we moved to Kyoto, so perhaps Kyoto is my hometown, after all. My earliest recollection is the image of myself on my mother’s back. I believe we were standing on the bridge that connected the railroad platform with the main building of Kyoto Station; I was half asleep. It was probably not the time of our arrival in Kyoto that I recall, because the image is much too vivid. I can see the dirty ceiling and the blackened windows of the covered bridge, and I can hear the steam whistle of the train.

There is another similar memory: I was being carried in a garden on someone’s back, probably one of the maids who served our large family. I can hear a sleepy lullaby and I am drowsy. The garden is covered with moss, and the white wall of the storehouse is bright with the thin rays of the winter sun. This memory seems to refer to the house in Somedono that I will describe later.

When our family arrived in Kyoto, we found that no house was available. We were supposed to rent a section of Engakuji Temple in Yanagifuro, close to the old Imperial Palace, but it was not ready for us. For a time, we settled in Sawabun Inn at Sanjo Fuya, where we had a very large room. The unsettled living in the Inn must have been hard on my mother. Father had preparations to make for his new position. The two pre-school boys played games beside the desk where Father was working. The baby, myself, must have been crying from time to time.

During this hectic time, a misfortune occurred. One night, Takuji, my father, began to run a high fever and complained that his arm hurt. At first my mother thought he was tired from carrying heavy luggage during the long trip. But his face became red with fever, and he said the pain was unusual. The arm hurt from shoulder to wrist and it was swollen. A doctor came from Kyoto University Hospital and the next day my father entered the hospital. My father was cured by an operation under full anesthesia; fortunately, no mistakes were made.

While my father was in the hospital, the family moved into the Engakuji Temple. It was hard for my mother to make the move with so many children. My parents had no relatives living in Kyoto, although both of them came from Kishu, not far away. Yanagifuro, where the temple is located, is still a quiet district; in those days it was at the lonely edge of town. In that year, only twelve years after the establishment of Kyoto Imperial University, the population of Kyoto numbered just over 300,000. We lived in the temple for about one year, and we changed houses fairly often after that, sometimes for the convenience of the landlord, but more often for our own reasons.

My father’s mother and my mother’s parents were living with us, my father having been adopted upon his marriage. After myself, my two younger brothers Tamaki and Masuki, were born. It was a large family — and on top of that, my father’s library was expanding rapidly!

My father, although a specialist in geology and geography, had wide interests and bought many books about other fields. For example, he was very fond of art. When interested in something, he could not rest until he had collected all possible writings on that subject. For instance, when he took up the game of go, he bought all the books on it that he could find. They would fill up the library and then spill into the study. When all storage places were full, my father would say to my mother, “We shall have to move again. Where can we find a larger house?” In those days, university professors must have been much wealthier than they are today!

My father rode to the University each day in a rickshaw and returned the same way. These hand-carts did not have rubber tires, and I can still remember the loud noise made by their wheels. But the family was not always well-off financially, because of the many books and art objects my father bought. Sometimes he doubted whether he could afford to send all his sons to the University to study. Without my mother’s strong urging, I might not have received university training, and I would not exist today as I am.

Although I do not believe in predestination, I cannot avoid a strange feeling when I think about this. A man cannot know in advance what will shape his career; I could not have known that an idea would come to me twenty years later that would make a contribution to physics, and that I would influence the shape of physics.

We moved finally to a house in Teramachi (Hirokoji Noboru, Somedono), just north of the Nashiki Shrine. The house had belonged to a nobleman connected with the household of the Emperor. Its garden was covered with moss. Our landlord, the aforementioned nobleman, was named Rokujō. I never saw him, but according to my older sister, he had a squarish face that was fierce and frightening to a child. Everyone called him “Deaf Rokujō-san.”

Where did this name come from? My older sister says that she can still remember him riding a horse, splendidly costumed during the annual Aoi Festival in Kyoto. I always thought he was really deaf, but my sister later told me that he had no physical defect in this regard, but only pretended not to hear when he was told something he did not like, so that the neighbors jokingly called him “deaf.” In those days, Kyoto had many noblemen with high ranks and thin wallets, and just as many with eccentric reputations — “Deaf Rokujō-san” was one of these.

The house was on Teramachi Street. The rooms at the back of the house were large and old-fashioned; my grandparents had their rooms on the second floor. To the left of the gate, set against the wall that surrounded our property, was a room with a high floor and a lattice window. I played there with my brother Shigeki, and we looked out on the street through the window. Even today, Teramachi is a narrow street. In those days a small street railway line ran on one side of the street, one of the oldest such lines in Kyoto. Today (in 1957), the street car runs on Kawaramachi Street, east of Teramachi, and the tracks have been removed from Teramachi.¹

On the other side of the street almost facing our house, was the main gate of the temple Shōjōkein, the headquarters of the Jodo sect of Buddhism. For some reason, we called this “Jōken Temple,” and my brothers often played on its grounds. As one entered its gate, the main temple building stood to the left. At the roof, one could see the chrysanthemum seal. Passing through the elevated corridor that connected the main building with the office and the priests’ living quarters, one looked over the cemetery. My brothers played hide-and-seek there, and I also sometimes played there, although I remember almost nothing about it. Wait, there is one thing —

My eldest brother, Yoshiki, was mature for his age and the next oldest, Shigeki, was full of confidence; I, the third son, was already conscious of pressure from the older boys. As I was running through the graveyard of “Jōken Temple,” I slipped and struck my head against a stone grave marker; I saw darkness for a moment. I started to cry, but my brothers were already far away. As I lay on my back, the sunbeams that shone through the leaves of the cherry trees hit my eyes, and I gasped: they were like countless stars — the midday stars! Much later, when the idea of the meson occurred to me, I caught a vaguely remembered glimpse of those midday stars.

My father, Takuji, traveled all over Japan doing geological surveys when he was a young man. At thirty years of age, he was appointed a delegate to an International Geological Conference in Paris. He was always intent on his work. To a child, that sort of scientist is sometimes too strict a father; at times he seemed insufficiently concerned about his child.

In later years, after I had been adopted by the Yukawa family, I used to return to visit my father. We would talk for hours, sometimes about our researches, sometimes about current issues. It was then that I discovered that he had another side. But when I was a child, he seemed to me a humorless man. Often he would say to my mother, “One shouldn’t spoil children.” And she would answer, “But they are still so small.” It does seem as if my father did not approve of childlike behavior in children!

I do not recall ever being hugged by my father. Neither did I ever ask him for toys. Perhaps he expected a child to have a man’s outlook. When I entered the Third High School in Kyoto (junior college level), the Headmaster, Sotosaburo Mori, said in his welcoming speech to my class, “From today on, I will treat you as gentlemen.” Mori was speaking to boys of seventeen and eighteen, and his speeches were famous in Japan. Perhaps my father’s attitude was a similar one.

Toward my brothers, his attitude was the same; I do not think any of them had ever been embraced by my father. His authority was absolute, and it was my mother’s duty to support it. She gave up her own personal life to take care of the children and the old people in the house. Mother might have done her own shopping once a month, but she always returned home as soon as she was finished. She did read a great deal, but that was also done for the children.

By today’s standards, Mother was very old-fashioned and there is no doubt that she accepted her household tasks as her obligation. Her only joy, it seemed, was in raising the children. She died in 1943, and had never seen a movie in her life. The very idea of pleasure seemed not to exist for her. As a child, I always felt sorry for her, and I still wonder if she was really satisfied with her life.

As my mother was always busy, I grew close to my grandmother, my father’s mother. Her name was Miē Asai. She was of an open and outspoken disposition and used to take me to visit the numerous Buddhist temples and Shinto shrines of Kyoto: Kyoto, seen from the stage of Kiyomizu; the autumn leaves of Tōfukuji Temple; Chion-in’s huge roof and its roof-tiles: The buildings and the natural beauty of Kyoto have made strong impressions on me.

Both my parents walked a path without lifting their eyes from it. Perhaps that is the heredity that led me to walk the path of science; yet, as a child, I was not fond of science. Although I received good grades in elementary school, I was far from a genius in middle school or in high school. My eldest brother, Yoshiki, likes to say jokingly, “Hidé was not a bright child; he was stubborn, and gave us trouble.” But I became very absorbed in my activities. When I was given building blocks to play with, I would do so by myself for hours at a stretch. Our house had a sunny veranda facing the garden which had bushes and stone lanterns, and I would play with the blocks there — building houses, gates, and towers.

How did this look to others? My father’s mother would bring me snacks. “Are you still playing with those blocks? What a busy child!” she would say in a kindly voice. As far as I could tell, the towers I built were as gorgeous as the Tower of Yasaka, and my houses as impressive as those of the Imperial Palace. “Grandma, I’ll make you the Honganji Temple.” I would take the tower apart and start the new task. When it was finished, my grandmother would say, “What a beautiful temple! I’ll have to make a pilgrimage to it.” Then she would pretend to pray.

One day Grandmother bought me a jigsaw puzzle of twelve pieces, with a brightly colored picture. I played the game of assembling it with great concentration, but after several times it became too easy. Nothing could have been easier once the completed picture was memorized, and my curiosity quickly faded as I noted, without effort, the shape of each piece. “Look, Grandma, I can do the puzzle face down!” I could not see any picture facing me but I put the pieces together, and when I flipped it over, there was the picture. “Well,” said my grandmother, “there is a bright child — perhaps the brightest in the family.” My grandmother thought highly of my capabilities, a feeling not shared by the rest of the family.

That grandmother died in the house at Somedono, and so I was lonely when we moved to another house, at Higashizakura. But I became the favorite of my grandparents on my mother’s side. The new house was owned by a viscount named Keishi Toyōka. The county hospital was nearby, and so was Kuninomiya Palace. Beyond the Palace flowed the Kamo River. Once a year, Rokusainenbutsu (a dancing incantation of Buddha) was performed inside the palace grounds, and on that day the public was admitted. A large go-board was placed in front of the gate, and on it a lion dance was performed. The bright orange and green of the lion’s costume, and its fierce-looking mask, impressed me deeply.

The gate of our house was like that of a temple; its roof-tiles were shaped like peaches. Inside the gate there was a shelter for the servants of visitors. After this shelter, there came the storage house, and then the main entrance, with a stoop in front. It was the old-fashioned house of a nobleman. I remember that several bamboo trees stood to the left of the gate, and a holly tree stood to its right.

As one passed through the wooden gate to approach the house, there was a courtyard to the right, in one corner of which stood a small shrine. Next to it was a detached room, which became the living room of my grandfather, Komakitsu. In the courtyard between this room and the main house, my grandfather cultivated morning glories and chrysanthemums. Once he took me to a morning glory competition. He also used to take me to see sumō wrestling.

The town is all changed now and it is hard to describe the exact location of the morning glory contest, wh...

Table of contents

• Cover
• Title
• Copyright
• Contents
• Foreword
• Chronological Table
• Introduction: Hideki Yukawa and the Meson*
• Chapter 1: The Home of Knowledge
• Chapter 2: My Father
• Chapter 3: Iwan (I won’t say)
• Chapter 4: Somedono
• Chapter 5: A Voyage
• Chapter 6: The Wave and the Wind
• Chapter 7: Episode
• Chapter 8: Youth
• Chapter 9: The Narrow Gate
• Chapter 10: Crystal
• Chapter 11: A Turning Point
• Chapter 12: Kurakuen
• Epilogue
• On the Interaction of Elementary Particles. I.