Science in Christian Perspective

YUKAWA: Naturalist, Traveler

Raymond J. Seeger

4507 Wetherill Road
Bethesda, MD 20816

From PSCF 40 (September 1988): 168-169.

Hideki Ogawa was born in 1907 in Tokyo, the third of five sons. His father Takuji was head of the geology research center, but became Professor of Geography at Kyota Imperial University (1897) when the boy was one. (Kyota had been the capital of Japan until 1869). His archaeological interests led to close connections with the Institute of Chinese Culture. He had the boy's maternal grandfather, a samurai with great learning in Chinese classics, teach Hideki to read the classics at five years of age. The next year Hideki entered the Kyogaku Primary School, where he developed a distaste for science. At twelve he went to the Kyota Prefectural First Middle School, where he developed a fondness for mathematics, but did not like physics. He also learned English and German. During the next year or two he read Taoism and Chuangtse, which he found in his father's voluminous library.

At sixteen, he entered The Third High School where he read the then-popular Tolstoy, though he gravitated towards Dostoevski later. He lost his interest in mathematics because of his teachers: the one in algebra emphasized memorizing, the one in geometry insisted upon verbatim repetition of the notes given. Engineering, too, was not attractive, owing to his poor draftsmanship. Although somewhat clumsy in a laboratory, he became fascinated by theoretical physics. He particularly enjoyed Jun Ishihara's Theory of Relativity and Fundamental Problems in Physics. He bought Planck's Introduction to Theoretical Physics I (General Mechanics, in German). He later remarked that the 1900 Leyden talk on "The Unity of the Physical Universe" was the "most outstanding" of Planck's lectures. He was intellectually stimulated, above all, by Fritz Reiche's Quantum Theory. At nineteen Hideki entered the Kyota Imperial University to study physics, graduating three years later. He spent the next three years there as an unpaid research assistant; his primary interests were the little-known fields of the atomic nucleus and of cosmic rays.

At twenty-five he married Sumi Yukawa, two years his junior, and was adopted by her family (taking on their name). He was made a lecturer at the Kyota Imperial University and then also at Osaka Imperial University the following year. A turning point in his life probably occurred when he met Professor Hidetsugu Yagi, head of the new Osaka Physics Department.

At twenty-seven, he presented a paper "On the Interaction of Elementary Particles I" at a meeting of the PhysicoMathematical Society of Japan. The paper predicted a new elementary particle, the meson, for which he received the 1949 Nobel Prize in physics at the age of forty-two (cf., the experimental discovery of the muon and of the ir meson). At twenty-nine he was made Associate Professor at Osaka, and received his Ph.D. from the University three years later. At thirty-two, he became Professor at Kyota. On his way back from a Solvay Conference in Europe, cancelled on account of WWII, he visited the United States. At forty-one he became Visiting Professor at the Institute for Advanced Study in Princeton, and the following year Professor at Columbia University. Four years later, he was appointed Director of the new Kyota University Research Institute for Fundamental Physics. He was made a member of the Japanese AEC at forty-nine. He died at the age of seventy-four in 1981.

He was awarded in 1940 the Imperial Prize of the Japan Academy, and in 1943 the Order of Decoration of Cultural Merit of Japan. He was made an Honorary Citizen of Kyota. Yukawa also received an honorary doctorate from the University of Paris. He was a Foreign Associate of the U.S. National Academy of Sciences and a member of the American Physical Society. He was an honorary member of the Royal Society of London, the Royal Society of Edinburgh, the Italian Academy of Science, and the Pontifical Academia Scientiarium, among others.

He founded and edited the English journal Progress of Theoretical Physics. He published two books, including Creativity and Intuition (I 973). An autobiography, Tabibito (the Traveler), written when he was fifty, was published posthumously in 1982. As a scientist from 1932 to 1934, he said: "I felt like a traveler carrying a heavy burden and struggling up a slope.... Those who explore an unknown world are travelers without a map; the map is the result of the exploration."

Early on, Yukawa set himself a daily schedule. Although docile in temperament, he had tenacity of purpose, perhaps even stubbornness. He continually sought new, difficult challenges. In later life, however, he deplored the plethora of miscellaneous information and the multitude of expected tasks. When young he was asocial; he never became quite adept in dealing with other people.

As he grew older, he appreciated more and more how science is intimately linked with society. He was anxious about thoughtless applications of science and fearful of "scientific wars." As a scientist, a Japanese, and a human being, he regarded the production of atomic energy as a turning-point for mankind. He was himself one of the eleven signatories of the Russell-Einstein Manifesto (1955) which was against the use of nuclear weapons and for the abolition of war. In view of the impotence of the United Nations, he favored a World Federation to insure peaceful coexistence by scrapping all armaments. In 1961, he was President of the World Association of World Federalists (made Honorary President in 1965). Although he attended the first Pugwash Conference on Science and World Affairs (1957), he became disappointed with the Association's increasingly bureaucratic operations.

He was discouraged also with the growing cultural estrangement of physics from other disciplines. Yukawa himself did not neglect the humanities, particularly, philosophy, history, and literature. He said, "I have always believed that literary beauty is not so far removed from the beauty that is revealed to us by theoretical physics." The novels he preferred early in life were of a melancholic mood, even pessimistic. His later appreciation of Lady Murasaki's The Tale of Gengi lightened the generally dark atmosphere of his literary tastes with only occasional flashes.

Looking backwards, he felt that "modern physics carries an echo of ancient philosophies" (e.g., Democritus'atom). In Epicurus' letters, he believed he saw the interesting current idea of the universe as nonborn and nondestructible. He admitted, however, that the old distinction between existence and nonexistence is becoming increasingly unclear in modern physics. The "chaos" of the Chinese philosopher Chuangtse (4th century B.C.), he felt, "is much akin to the world of elementary particles."

Yukawa had an open world view: the great unknown touching the ever-changing known. He wondered about an invisible mold that apparently produces all electrons alike, and about DNA that chance may have caused but that reproduces itself. In it all, however, he felt the mystic unity of nature emphasized by Planck: "To strive towards such a goal is surely, even today, the most essential justification of physics." He believed, however, that our perception of nature is diminishing owing to the increasing alienation of theory from human senses: "I have felt more and more strongly my estrangement from contemporary physics in spite of the fact that I myself am a physicist." He preferred the simpler general relativity to the more abstract quantum mechanics: "When one turns back to one's own views on life and endeavors to relate physics to some sense of purpose, one begins to have the greatest doubt. Indeed, one wonders if they have any, reference to the purpose of life at all."

Yukawa bemoaned the lack of any adequate metaphysics "to discover the truth." He noted the plentifulness of professors of philosophy. but the dearth of any philosophies. In his own case he found that the ideas of the Chinese philosopher Laotse (604-531). the father of Taoism, and of his follower Chuangtse seemed "most modern." Both placed nature at the center of their thinking, man being unhappy apart from nature and punv in attempting to resist it. In the case of the atomic bomb. he found man actually subservient to nature. A favorite quotation was from Laotse: "Heaven and Earth are without compassion; they see all things as straw dogs" (i.e., ceremonial objects destroyed after their use). "Man's efforts on behalf of man are all the more meaningful. Here .... lies the only purpose in life that makes life worth living." He felt that Laotse had unknowingly given a scathing indictment of scientific culture-long before its advent. Yukawa admitted, "We today, have come to cherish very fundamental doubts as to where scientific progress is leading." For him both Laotse and Chuangtse suggested a fatalistic naturalism, "like that to which the scientific view of nature may ultimately lead."

On the other hand, Yukawa seemed at times to favor another more helpful Chinese mentor, Motse (480-390?), who was a rationalist and a pacifist. His doctrine of "Chienai" ("dual love"- close to the second great commandment of Christ) is that one should love one's self and others-not self-sacrifice. Yukawa believed that "no approach could be better suited to mankind today, for whom survival and prosperity is peaceful coexistence." Motse showed a strong theistic tendency; his Heaven is anthropomorphic, where there are demons and spirits.

Yukawa represented a strange interfusing of the old East and the new West-where the 'twain now meet-in science.

Twenty-second in a series by Raymond J. Seeger about scientists and their religion.