New Kyurizukai
Over the years Dr. Yukawa has taken up and persistently pursued hobbies and sports, such as soroban (abacus, a traditional calculation tool), table tennis and dancesport, which appear to be minor (in Japan) yet are of great depth. This attitude overlaps with his mindset as a researcher who devotes himself to the theoretical side of studies rather than jumping at themes in fashion. Behind his way of life were valuable encounters with good friends and respected teachers, not to mention the support from his family.

What was your childhood like?
      As far as I was told by my mother, I was a very talkative boy, who often reported to my nursery school teacher about everything that had happened at home the day before. To make the matter worse, I spoke out clearly and in an easy-to-understand way. Later my mother complained to me that she had felt pretty embarrassed (Laughter).
      I have a sister four years older than me. As a small boy, I used to follow her and play house with her. This gave me a nickname “shadow-like follower” (Laughter).
      I was born in Minami-Ashigara City, Kanagawa Prefecture. Both my father and mother were public servants, father working for the Odawara City Office and mother for the Ministry of Finance’s Printing Bureau. Both of my parents were good at math in their school days. Presumably having inherited their genes, they say I was good at mental calculation since my nursery school days. But I have few memories of those days. The only thing I still member is that, as an elementary school boy, I often went shopping with my mother, when I did sums in my head.
      Because of my mathematical interest, I was very fond of riddles, quizzes and puzzles and loved reading books about mathematics.
      Soon after entering the elementary school, I attended a soroban school. Thanks to a good teacher, I liked the art of soroban and continued to learn it up to the end of junior high school second year. I hold a first dan license in soroban and a third dan license in mental calculation. On the occasions of soroban competitions, I was always among the best; at an All Kanagawa Prefectural soroban competition when I was an elementary school sixth grader, I became the champion in the category of calculating figures read off aloud. Even today I still do two-digit addition and multiplication by mental calculation – not so well as in the past, though.
      I used to teach arithmetic and mathematics to my friends. Looking back now, I may also have learned something by teaching them. I’m still grateful to my friends.

Were you an indoor-oriented boy?
      I don’t think so. An expanse of rice fields could be found around my house, so rice and flower fields were ideal playgrounds for us children. Actually I was an active elementary school boy; the moment recess time began, I dashed out of the classroom into the schoolyard to enjoy ball playing with classmates. There was also a period when I went to school at 6:00 in the morning just to practice long-distance running together with my friends – a cherished memory now.In my junior high school days, I served as captain of the table tennis club and even participated in the prefectural tournament. The more I exercised, the better I slept at night (Laughter).
      Meanwhile, at one time I was crazy about “Famicon” video game machine and “Game Boy” handheld game device. I played and played these games until I got sick of them. Having done too much, I said good-bye to these games (Laughter).

Didn’t your parents tell you to study hard?
      No, they didn’t. My parents never criticized me about my attitude about studies because I did at least what I should do – I did homework as assigned and listened carefully to classroom lessons. I’m grateful to my parents for basically allowing me to do whatever I liked. When I was an elementary schoolboy, I was making a plastic model and badly soiled the carpet surface here and there with a sticky bond. Even at that time I remember they didn’t scold me at all. As parents they must have been very generous.
      Following entry to a local junior high school, I began to attend a small cram school in my neighborhood partly because of my elder sister’s influence. Thanks to the cram school teacher’s enthusiastic guidance, I became more and more interested in mathematics. In those days, however, I wanted to become a certified public accountant in the future, not a researcher.
      As for senior high school, I chose Prefectural Atsugi High School, which was outside of my school district. It was my routine to make a 40-minute trip one way on the Odakyu Line train while reading the mathematics textbook on board. Presumably, this experience may have made my backbone as a researcher as I am today.
photo      From halfway through the first year to the end of the second year, one of my schoolmates and I took up a part-time job at a co-op store near my high school – for a bit of real-world experience and earning pocket money. There I was assigned to the deli corner, so it became my special skill to neatly wrap food in cellophane. Once I demonstrated this skill and surprised my wife (Laughter).
      After all, I spent most of the money I earned from this part-time job for music, buying an acoustic guitar and so on. I liked to chant numbers from “SPITZ” (a Japanese rock band) and other J-Pop artists to my own accompaniment, but I was too shy to appear in front of an audience … (Laughter).
      As a high school third grader, I began to think seriously about the university entrance exam and began attending a prep school aiming to enter the engineering course. On the occasion of the school’s autumn cultural festival, all of us classmates were excited to bring our dancing performance and other programs to success. It seems to me that the extraordinary energy I exhibited during the festival somehow fueled my last spurt for the university entrance exam.