Heredity or environment, nature or nurture, there is no general solution to the problem of how much each contributes to the structure of a personality or the achievements of a person. It has been said that any medical student can become an adequate surgeon provided he or she is willing to work long hours, follow the hospital rules, and placate the nursing staff. In other words, this particular skill is not significantly determined by genetic factors. No such prescription can be applied to mathematical physics; original work in this field requires a special kind of native aptitude, the genes must be right. This is a necessary but not a sufficient condition. A potential schrödinger may be lost to physics if he happens to be born in a Bengali village rather than a university town.

Many theoretical physicists have come from academic families, which, at least in Germanic countries, are considered to be upper middle class on the social scale. The fathers of Max Planck, Niels Bohr, Max Born, Wolfgang Pauli and Werner Heisenberg were all university professors, of Law, Biology, Anatomy, Colloid Chemistry and Byzantine Studies, respectively. Paul Dirac's father taught French at a Bristol grammar school, in the English context, a respected but lower-middleclass profession; Paul originally aspired only to be an engineer, but turned to pure theory after his ineptness in practical work became evident. Albert Einstein's lower-middle-class background was exceptional among German scientists. The Einsteins lived in an industrial suburb of Munich, and the early stages of Albert's scientific career were unusually precarious.

Thus the ancestry and family history of Erwin schrödinger are relevant to the story of his life, even if the relative contributions of genetics and economics cannot be clearly separated. Fortunately his Aunt Rhoda compiled a history of his mother's side of the family; less is known about the schrödinger side.

Family history

The story begins with Franziska Zickler, who was a love child of unknown parentage, born about 1780 in a convent in Hungary where her mother had taken refuge. From certain resemblances, it was thought that she may have been related to Josef of Habsburg-Lorraine, a son of Maria Theresia. She grew up to be a temperamental beauty and married a member of the minor nobility, Anton Wittmann- Denglass who was born at St Bernard in Lower Austria in 1771.

When the Great War began in August, 1914, Erwin schrödinger at the age of twenty-seven was a Privatdozent at Vienna University, at the outset of a promising career in physics. He served throughout the war as a commissioned officer in the Austrian fortress artillery, first on the Italian front and later assigned to the imperial meteorology department in Vienna. On October 7,1915, his revered professor of theoretical physics, Fritz Hasenöhrl, was killed by a grenade in an Italian attack on Mount Plaut in the South Tirol.

Early in 1918, schrödinger received word that he was being seriously considered for the position of Professor Extraordinarius [associate professor] in theoretical physics at the University of Czernowitz. ‘I made up my mind to lecture there on honest theoretical physics, first of all according to the pattern of the splendid lectures of my beloved teacher Fritz Hasenöhrl, fallen in the war, but besides to concern myself with philosophy, deeply immersed as I then was in the writings of Spinoza, Schopenhauer, Mach, Richard Semon, and Richard Avenarius. My good angel intervened, since soon Czernowitz no longer belonged to us. So nothing came of it. I had to stick to theoretical physics, and, to my astonishment, something occasionally emerged from it.’ Even on active duty, schrödinger found time to read deeply in philosophy, and indeed it was the only thing that kept him from despair during the long years of senseless killing and destruction.

A serious interest in philosophy was not unusual among German and Austrian physicists, but with schrödinger at that time it was so important that he was even tempted to sacrifice scientific research to devote his life to philosophical study. Much later, in 1963, Max Born wrote: ‘I am convinced that theoretical physics is actually philosophy. It has revolutionized fundamental concepts, e.g., about space and time (relativity), about causality (quantum theory), and about substance and matter (atomistics). It has taught us new methods of thinking (complementarity), which are applicable far beyond physics.’ By his discovery of wave mechanics, Erwin schrödinger contributed in a major way to this revolutionary change in our view of the world [Weltanschauunung].

After five years of World War II, the end of the conflict and the defeat of Germany and Japan could be foreshadowed, so that the Irish ‘Emergency’ was becoming less anxious, although shortages of supplies and restrictions on travel were scarcely improved. schrödinger no longer confined his intellectual work to unified field theory and he began to take an interest in a variety of other problems, including some of a more philosophical nature. Physically, as he neared the age of sixty, he enjoyed good health, despite annual attacks of respiratory illness, aggravated by the dismal Irish climate and excessive smoking. When springtime came, Dublin broke out with great masses of yellow daffodils for sale at almost every corner and as he strolled down O'Connell Street Erwin exclaimed in joy at the sight of all the pretty girls who had emerged from winter coats to warm themselves in the occasional midday sunshine.

Statistics again

From January to March, 1944, schrödinger had returned to one of his first loves in science in a course of lectures on Statistical Thermodynamics at D.I. A.S. They were published in a small hectographed edition and later (1946) by the Cambridge University Press.1 In less than one hundred pages he covered the fundamentals of the subject with an insight and clarity that have never been equaled. The book is a distillation of his many years of creative work in the field, and one hears echoes of the passionate discussions of the twenties with Planck, Ehrenfest, and Einstein. He was pleased to learn that Max Born liked the little book on statistics, and wrote to him: ‘For I have no higher aim than to work out the beauty of science. I put beauty before science. Nitimur in vetitum [Ovid: we strive for that which is forbidden]. We are always longing for our neighbour's housewife and for the perfection we are least likely to achieve.’

During 1944 schrödinger exchanged several letters with Lajos Janossy (1912-1978), a Hungarian physicist who had attended some of his courses in Berlin, and who was now working on cosmic rays with Patrick Blackett in Manchester. He had become interested in a note by Janossy in Nature on the statistics of coincidences in Geiger counters - anything to do with statistical problems attracted his attention, and he would put aside even his general field theory to deal with it.

When schrödinger returned from his summer holidays for the winter semester of the academic year 1925/26, he would have been quite unaware that he was on the verge of an outburst of creative activity that would change forever the world of physics. He had just reviewed and codified his personal world view and it was unlikely that his philosophical outlook would change in any revolutionary way. He had set down his belief in Vedanta and thus in Schopenhauer, through whom the Kantian a priori categories of space and time had been refurbished. During five carefree years in Switzerland, he had been insulated from both the hypocrisy of Vienna and the brutality of German politics. It would not be surprising if Swiss society, with its deep roots in economic security, had made him more conservative in other ways. His more unconventional beliefs, he kept to himself, and neither his inaugural lecture nor My World View was published at this time.

Hermann Weyl once said that schrödinger ‘did his great work during a late erotic outburst in his life’. His marriage with Anny was at a high point of disagreement and tension, with constant talk of breakup and divorce. Their zürich circle provided ample opportunities for amorous adventures, and if Erwin cared to venture outside the usual academic liaisons, both Weyl and Debye were available as competent guides to the uninhibited night life of the city.

Before the breakthrough

The semester began on October 15, and schrödinger had his usual heavy teaching schedule, five hours a week on Theory of Electricity, two hours on Theory of Spectra, a weekly seminar for the electricity course, and the joint seminar with E.T.H., which met for two hours every fortnight. Pieter Debye suggested that Erwin should give a seminar talk on the de Broglie thesis, which had just been published in Annales de Physique.

In the midst of all the postwar turmoil and suffering, Erwin took no respite from his intensive research at the Physics Institute. He also filled notebook after notebook with commentaries based upon his reading of European and Eastern philosophers. It was in these dying days of the Danube Empire that he formed the foundations of his philosophy, which was to remain remarkably constant all his life. His interest in philosophy at this time was so intense that he even considered the possibility of devoting his intellectual life to that field. It would have been an inopportune decision, since philosophers now began to consider their subject as a self-contained discipline pursued by specialists for academic ends. Wittgenstein's Tractatus Logico- Philosophicus became the bible of the Vienna School of logical positivism. ‘What is history to me?’, he wrote, ‘Mine is the first and only world’. The task of trying to repair the wreckage of European civilisation may, however, have been hopeless even if help from the philosophers had been forthcoming.

Schopenhauer

Erwin read everything written by Schopenhauer. The luminous words of the philosopher of pessimism were perfectly suited to the world of 1919, and in that context may even have had a consoling effect, making some sense of Europe's four years of self destruction.

Arthur Schopenhauer (1788-1860) was born in Danzig, the son of Heinrich, a rich Hanseatic merchant, and Johanna, a romantic novelist. As a youth, he traveled widely, becoming fluent in English and French, so that his prose style acquired a lightness and clarity quite unlike the murky philosophic German of his times. His first education was that of a man of the world, only later did he obtain the usual academic credentials. He became a friend of Goethe, and in 1816 wrote a small book on color theory inspired by the ideas of the older man.

Schopenhauer regarded himself as the true spiritual descendant of Kant, and he did not hide his view that Hegel, then at the height of his fame, and other university philosophers were charlatans who had perverted the Kantian gospels.

In this book I have tried to tell something of the life of Erwin schrödinger in such a way that even those who are not scientists may be able to understand the greatness of his work, the range of his ideas, and the kind of person he was. Montaigne wrote that ‘our life is divided betwixt folly and prudence: whoever will write of it only what is reverend and canonical will leave about the one-half behind’. In order to come closer to the whole of schrödinger, I have included some account of his personal life. It is not thirty years since his death and thus many personal memories and sensitivities have not yet receded into history, a situation that is both a help and a hindrance for a biographer. It is possible to interview former friends and colleagues, but some important collections of letters and memoirs remain closed to research.

My book was made possible by the generosity with which schrödinger's eldest daughter, Mrs Ruth Braunizer, made available many of the archives concerning her father's life.

Special thanks are due to Professor Ludvik Bass of the University of Queensland, schrödinger's last postdoctoral student, who reviewed the entire manuscript; his scientific and historical comments have been invaluable.

Dr Linda Wessels of Indiana University provided many helpful suggestions. Professor James McConnell of the Dublin Institute for Advanced Studies never failed to answer my seemingly endless questions about schrödinger's Dublin years. Dr Anthony Bracken reviewed several theoretical sections; Professor David MacAdam clarified some of the difficulties of color theory. My friend and neighbor, Robert Halporn, assisted in the decipherment of Gothic script and in explaining life in Vienna and the Austrian educational system. Dr John Fletcher helped with the study of schrödinger's poetry. Professor Sture Nordholm provided translations of the Nobel Archives, and Dr Kirsten Streib translated some of Niels Bohr's letters from the Danish. Professor Karl v. Meyenn of Barcelona made available unpublished material about schrödinger in Spain, and Professor Kenji Sugimoto shared his collection of photographs. My family was enlisted in various ways: Professor Joseph Wiecha as consultant on German language and literature, my sister Mary Wiecha for comments on style and content, and my nephew Dr John Wiecha for one of the interviews.

Erwin began his career in physics during the last peaceful years of the Danube monarchy. Old Franz Josef still retained the respect and affection of the lower and upper classes among his subjects, but his control over the bourgeois politicians and their nationalistic tendencies began to falter. The Hungarian leaders consistently placed the privileges of the great Magyar landowners above all else, and extorted special concessions as the price of loyalty to the throne. The annexation of Bosnia-Herzegovina in 1908 created a large population of disaffected Slavs and Muslims in the southern borderlands. The K&K structure was becoming more unstable, and as for a radioactive atom, the question was not if but when it would disintegrate.

Before the war

The chief of the general staff, Franz Conrad, was a persistent warmonger, urging the emperor to embark upon ‘preventive war’, one year against Serbia, the next against Italy. At the end of 1911, he was dismissed, not so much for meddling in foreign policy as for his affair with a married woman, Gina Reininghaus, which offended the religious sensibilities of the old emperor. After a year in disfavor, he was called back, but soon thereafter Franz Ferdinand, heir to the throne, was appointed General Inspector of all the Armed Forces. In May, 1913, the war machine was shaken by the revelation that Colonel Alfred Redl, one of the chiefs of military intelligence, was a Russian spy and a member of a homosexual coterie among the army officers. Since he had sold the Russians all the plans for a prospective eastern theater of war, a hasty revision of K&K strategy was required. Meanwhile, the two Balkan wars of 1912-1913 had left Serbia as a much stronger military force in the region. Even Conrad realized that it was now too late for preventive war.

The musical, literary, and dramatic life of Vienna still made the city the cultural center of the German-speaking world, but this eminence was increasingly a creation of the Jews. In October, 1912, the Censorship prohibited the Wiener Deutsches Volkstheater from presenting Schnitzler's play Professor Bernhardi, which deals with antisemitism in the medical profession. Many Jews became converted to Christianity, and a few even to antisemitism.

Vienna is the second-oldest German-speaking university, founded in 1365 by Pope Urban V, seventeen years after the University of Prague. Albert of Saxony, formerly rector of the University of Paris, brought the hitherto secret statutes of that establishment to Vienna as a basis for the new university, and he became its first rector. Students came from all over Europe, but especially from the four nations, Austria, Bohemia, Saxony, and Hungary.

In the sixteenth century, the university joined the battle against Lutheranism, but not without misgivings, since most of the Viennese had become convinced Protestants. In 1550, the Jesuits were called into Vienna, where they established a number of excellent lower schools. The counter-reformation now began in earnest, with many expulsions and a few burnings at the stake, until Catholicism was firmly re-established in the Habsburg lands after a struggle of one hundred years. The professors for the most part resisted the clerics until 1617, when the university was formally united with the Society of Jesus. The Society was a militant order, and no sooner had it achieved its aims, than it began to lose interest in the university and to look for other enemies, which it found in the Dominicans who had refused to swear an oath to the Immaculate Conception of Mary.

In 1683 the Turks appeared in force at the gates of the city. The court fled but the burghers and soldiers defeated the Turkish army, and this siege marked the high point of the Moslem invasions, as the power of the crescent gradually receded from Europe. One thing Vienna learned from the Turk was a love for coffee, and coffee houses soon rivaled university class rooms as centers of intellectual activity.

Charles VI made extensive reforms in the university studies, which he directed more toward the service of the state and less to that of the church. His daughter, the Empress Maria Theresia, who gave Francis I five sons and eleven daughters, embraced the spirit of the Enlightenment with increasing fervor and encouraged the university to develop in new directions. She also provided funds for a magnificent new building, which was opened in 1756 with great celebrations. In 1780, Josef II issued a patent of tolerance, which abrogated the Catholic oath; Protestants and even Jews were admitted to degrees, but not women of any persuasion.

schrödinger had accepted an invitation from the University of Wisconsin to give a course of lectures early in 1927; they would pay $2500, which included an allowance for travel costs.1 He sent a paper to Physical Review which was published in the December, 1926, issue, so that the American physicists would have an excellent summary of his work on wave mechanics, and he would not need to review all the fundamentals when he lectured at American universities. Shortly before he left for America, he heard that he was a leading candidate for the succession to Max Planck at the University of Berlin.

American voyage

On December 16, Erwin and Anny attended a Christmas and Farewell Party held in the Physics Institute of the University. Edgar Meyer was master of ceremonies, and he recited one of the long doggerel poems for which he was famous. It included the verses:

Since Edgar Meyer always had some basis for his verses, it is likely that considerable urging was necessary to get Erwin to leave zürich and thereby sacrifice his Christmas vacation.

They set out on December 18 for the new world, by train to Basel and Paris, and then the boat train to Le Havre where they boarded the French liner de Grasse for a ten-day voyage to New York. Erwin grumbled from the beginning. He found his fellow passengers distinctly unattractive ‘examples of the modern “society” that I usually manage to keep at arm's distance.’ At dinner he was seated between two painted and powdered ladies ‘beyond the canonical age’ and he found the ‘hard, ruthless expressions’ of their consorts equally repulsive. Their French manners, for him, made the bad company even worse. His disposition was not helped by the fact that he was cooped up in a small cabin with Anny, who was frightfully seasick throughout the voyage.