Autobiographical Sketches

I lived far apart from my best friend, actually the only close friend I ever had, for the greater part of my life. (Maybe that is why I have often been accused of flirtatiousness instead of true friendship.) He studied biology (botany to be exact); I physics. And many a night we would stroll back and forth between Gluckgasse and Schliisselgasse engrossed in philo- sophical conversation. Little did we know then that what seemed original to us had occupied great minds for centuries already. Don’t teachers always do their best to avoid these topics for fear that they might conflict with religious doctrines and cause uncomfortable questions? This is the main reason for my turning against religion, which has never done me any harm.

I am not sure whether it was right after the First World War or during the time I spent in Zurich (1921-7) or even later in Berlin (1927-33) that Franzel and I spent a long evening together again. The small hours of the morning found us still talking in a cafe on the outskirts of Vienna. He seemed to have changed a lot with the years. After all, our letters had been few and far between and of very little substance. I might have added earlier that we also spent our time together reading Richard Semon. Never before or after did I read a serious book with anyone else. Richard Semon was soon banned by the biologists, since his views, as they saw them, were based on the inheritance of acquired characteris- tics. So his name was forgotten. Many years later I encoun- tered him in a book (Human Knowledge?) by Bertrand Russell, who devoted a thorough study to this genial biologist, stress- ing the significance of his Mneme theory. Franzel and I did not see each other again until 1956. This time it was a very brief encounter in our flat in Vienna, Pasteurgasse 4, while others were present, so that those fifteen minutes are hardly worth mentioning. Franzel and his wife lived across the border, our northern one, unhampered by the authorities, it seemed; nevertheless, leaving the country had become rather difficult. We never met again: two years later he died very suddenly. Today I am still friends with his charming nephew and 168 ERWIN SCHRODINGER niece, his favourite brother Silvio’s children. Silvio, the youngest in the family, was a doctor in Krems, where I went to see him when I returned to Austria in Ig56. He must have been seriously ill already, for he died not long afterwards. One of Franzel’s brothers, E., is still alive. He is a respected surgeon in Klagenfurt. E. once took me up the Einser (Sextener Dolomites) and, what’s more, saw me safely down again. I am afraid we have lost contact, driven apart by our different views of the world. Shortly before I entered the University of Vienna in I g06, the only university I was ever enrolled in, the great Ludwig Boltzmann met his sad end in Duino. To this day I have not forgotten the clear, precise and yet still enthusiastic words with which Fritz Hasenohrl described Boltzmann’s work to us. Boltzmann’s scholar and successor held his inaugural address in autumn I g07 in the primitive lecture hall of the old Tiirken- strasse building without any pomp or ceremony. I was deeply impressed by his introduction, and no perception in physics has ever seemed more important to me than that of Boltzmann - despite Planck and E:instein. Incidentally, Einstein’s early work (before Ig05) shows how fascinated he too was by Boltz- mann’s work. He was the only one who took a major step beyond it by inverting Boltzmann’s equation S == k 19 W. No other human being had a greater influence on me than Fritz Hasenohrl - except perhaps my father Rudolph, who in the course of those many years we lived together drew me into conversations concerning his many interests. But more about that later. While still a student I made friends with Hans Thirring. This turned out to be a lasting relationship. When Hasenohrl was killed in action in I 9 I 6, Hans Thirring became his successor; he retired at seventy, forgoing the privilege of remaining for the honorary year and leaving Boltzmann’s professorial chair to his son, W al tel’. After Igl I, while I was assistant to Exner, I met K. W. F. Kohlrausch, and yet another lasting friendship began. Kohl- rausch had made his name by proving experimentally the existence of the so-called ‘Schweidle Fluctuations’. In the year Autobiographical Sketches 16g before the outbreak of the war we worked together on the research of ‘secondary radiations’, which produced - at the smallest possible angle on small plates of varying material- a (mixed) beam of gamma rays. I learnt two things in those years: firstly that I was not suited to experimental work, and secondly that my surroundings and the people who were part of them were no longer capable of making experimental progress on a big scale. There were many reasons for this, one of them being that in charming old Vienna well-meaning blunderers were placed, often according to seniority, in key positions, thus impeding all progress. If only it had been realized that per- sonalities with great mental capacities were needed, even if it meant bringing them in from afar! The theories of atmospheric electricity and radio activity were both originally developed in Vienna, but anyone who felt really dedicated to their work had to follow those theories wherever they had been passed on. Lise Meitner, for instance, left Vienna and went to Berlin. But back to myself: in retrospect I am very grateful that because of my reserve officer’s training in Iglo/I I I was appointed assistant to Fritz Exner and not to Hasenohrl. It meant that I was able to experiment with K. W. F. Kohlrausch and make use of a number of beautiful instruments, take them to my room, especially the optical ones, and dabble with them to my heart’s content. Thus I could set the interferometer, admire the spectra, mix colours, etc. This was also how I discovered - through the Rayleigh equation - the deuter anomaly of my eyes. Moreover I was committed to do the long practical course, so that I learnt to appreciate the significance of measuring. I wish there were more theoretical physicists who did. In Igl8 we had a kind of revolution. The Emperor Karl abdicated and Austria became a republic. Our everyday life remained much the same. However, my life was affected by the breaking up of the Empire. I had accepted a post as a lecturer in theoretical physics in Czernowitz and had already envisaged spending all my free time acquiring a deeper knowledge of philosophy, having just discovered Schopenhauer, who intro- duced me to the Unified Theory of the Upanishads. E R VV I NS C H R 6 DIN G E R For us Viennese the war and its consequences meant that we could no longer satisfy our basic needs. Hunger was the punishment the victorious Entente had chosen in retaliation for the unlimited V-boat war of their enemies, a war so atrocious that Prince Bismarck’s heir and his followers could only outdo it in quantity, and not in quality, in the Second World War. Hunger prevailed throughout the country except on the farms, where our poor women were sent to ask for eggs, butter and milk. Despite the goods with which they paid - knitted garments, pretty petticoats, etc. - they were sneered at and treated like beggars. In Vienna it had become virtually impossible to socialize and entertain friends. There was simply nothing to ofTer, and even the simplest dishes were reserved for Sunday lunch. In some ways this lack of social activities was compensated by the daily visit to the community kitchens. The Gemein- schaflskuchen were often referred to as Gemeinheitskuchen (Gemein- schafl == ‘community’; Gemeinheit == ‘a mean trick’). There we met for lunch. We had to be grateful to the women who considered it their responsibility to create meals out of nothing. I t is no doubt easier to do this for 30 or 50 people than for three. Besides, relieving others of a burden must in itselfbe rewarding. My parents and I met a number of people with similar interests there and some of them, the Radons, for example, both of them mathematicians, became great friends of our family. I believe that in one way my parents and I were particularly disadvantaged. At that time we lived in a large flat (actually two flats made into one) on the fifth floor of a rather valuable building in the city, which belonged to my mother’s father. It had no electric light, partly because my grandfather did not want to pay for having it installed and also because my father, in particular, had become so used to the excellent gas light at a time when light bulbs were still very expensive and ineffi- cient that we really saw no need for them. And we had the old tiled stoves removed and replaced by solid gas stoves with copper reflectors - servants were hard to come by in those Autobiographical Sketches days, and we had hoped to make things easier for ourselves. Gas was also used for cooking, although we did still have an enormous old wood-burning stove standing in the kitchen. This was all very well until one day one of the higher bureaucratic offices, probably the city council, decreed that gas was to be rationed. From that day on every household was allowed one cubic metre per day regardless of how the fuel had to be used. If anyone was found using more, they were simply cut off. In the summer of 1919 we went to Millstadt, Carinthia, and my father, who was sixty-two, sho\ved the first signs of ageing and of what was to be his final illness, a fact we did not become aware of at the time. Whenever we went for a walk he would lag behind, especially where it got steep, and he would feign botanical curiosity to mask his exhaustion. From about 1902 on Father’s main interest was botany. During the summer months he collected material for his studies, not for setting up a herbarium of his own, but for experimenting with his microscope and microtome. He had become a mor- phogeneticist and phylogeneticist and had abandoned his dedication to I taly’s great painters and also his own artistic interests, which consisted of sketching innumerable land- scapes. Father’s rather bored reaction to our coaxing: ‘Oh, Rudolph, do come on’ and ‘Mr Schrodinger, it’s getting rather late’, did not alarm us either; we were actually used to that; so we put it down to his absorbed concentration. After our return to Vienna the signs became more apparent, but still we did not take them seriously as a warning: frequent and heavy bleeding from his nose and retina, and finally fluid in his legs. I think he knew long before everyone else that his end was near. Unfortunately this was just the time of the gas calamity mentioned above. We acquired carbon lamps, and he insisted on tending them himself. A dreadful stench spread from his beautiful library, which he had turned into a carbide laboratory. Twenty years earlier, when he had learnt to etch with Schmutzer, he had used the room to soak his copper and zinc plates in acids and chlorinated water; I was still at school then, and had shown great interest in his activities. But now I ERWIN SCHRODINGER left him to his own devices. I was glad to be back at my beloved physics institute after serving in the war for almost four years. Besides, in autumn 1919 I became engaged to the girl who has been my wife for forty years now. I do not know whether my father had adequate medical treatment, but what I do kriow is that I should have looked after him better. I should have asked Richard von Wettstein, who was after all a good friend of his, to seek help at the medical faculty. Would better advice have slowed down his arteriosclerosis? And if so, would it have been to the advantage of a sick man? Only Father was fully aware of our financial situation after the closing down of our oilcloth and linoleum store on the Stephansplatz in 1917 (due to lack of stock). He died peacefully on Christmas Eve 1919, in his old armchair. The following year was that of rampant inflation, which meant the depreciation of Father’s meagre bank account, which would never have kept my parents’ heads above water anyway. The proceeds of the Persian rugs he had sold (with my consent!) dissolved into nothing; gone for ever were the microscopes, the microtome and a good part of his library, which I gave away for a song after his death. His greatest worry during the last months had been that at the ripe old age of thirty-two I was earning virtually nothing - 1,000 Austrian kronen (before tax, that is, for I am sure he listed it in his tax declaration except when I was an officer during the war). The only success of his son that he lived to see was that I had been offered (and had also accepted) a better-paid post as private lecturer and assistant to Max Wi en inJena. My wife and I moved to Jena in April 1920, leaving my mother to fend for herself, in fact which I am not at all proud of today. She had to bear the burden of packing and clearing the flat. Oh, how blind we all were! Her father, who owned the house, was rather worried after my father’s death about who would pay the rent. We were in no position to do so, and Mother had to make room for a more affluent tenant. My future father-in-law kindly turned up with the man, a Jewish businessman working for the Phoenix, a prosperous insurance Autobiographical Sketches 173 company. So Mother had to leave, where to I do not know. Had we not been so blind we would have foreseen - and thousands of similar cases would have proved us right - what an excellent source of money the big, well-furnished flat could have proved for my mother had she lived longer. She died in the autumn of 1921 of cancer of the spine after what we believed had been a successful operation on her breast cancer in 1917. I rarely remember dreams, and I seldom had nasty ones - except maybe in my early childhood. For a long time after my father’s death, however, a nightmare kept recurring again and again: my father was still alive and I knew I had given away all his beautiful instruments and botanical books. What was he to do now that I had rashly and irretrievably destroyed the basis of his intellectual life? I am sure it was my guilty conscience that caused the dream, as I had cared so little for my parents between 1919 and 1921. This can be the only explanation, as I am not normally bothered with nightmares or a guilty con- science ei ther. My childhood and adolescence (1887-1910 or thereabouts) was mainly influenced by my father, not in the usual educa- tional manner, but in a more ordinary way. This was due to his spending a lot more time at home than most men who work for a living and to my being at home, too. In my early years of learning I was taught by a private teacher who came to see me twice a week, and at grammar school we still had the blessed tradition of attending for twenty-five hours a week, mornings only. (On two afternoons only we had to attend for protestant religious education.) I learnt a great deal on those occasions, although the result was not always related to the subject of religion. Time limita- tions concerning school commitments are a great asset. If a pupil feels inclined, he has time for thinking, and he can also take private lessons in the subjects which are not part of the curriculum. I can only find words of praise for myoid school (Akademisches Gymnasium): I was rarely bored there, and when it did happen (our preparatory philosophical course was really bad), I would turn my attention to some other subject, my French translation, for example. 174 ERWIN SCHRODINGER At this point I should like to add a remark of a more general kind. The discovery of chromosomes as the decisive factors in heredity seems to have given society the right to overlook other better-known but equally important factors such as communication, education and tradition. It is assumed that these were not so important because from the point of view of genetics they are not stable enough. This is quite true. However, there are cases such as that of Kaspar Hauser, for example, and that of a small group of Tasmanian ‘Stone Age’ children who were only recently brought to live in English surroundings and granted a first-class English upbringing, with the effect that they reached the educational level of upper-class Englishmen. Does this not prove to us that it takes both a code of chromosomes and civilized human surround- ings to produce people of our kind? In other words, the intellectual level of every individual is bred by ’nature’ and by ’nurture’. Schools are therefore (not as our Empress Maria Theresa liked to see it) invaluable for human guidance, and much less for political purposes. And a sound family back- ground is just as important for preparing the soil for the seed the schools will sow. This is unfortunately a fact overlooked by those who claim that only the children of the less educated should attend schools for higher education (will their children be excluded for the same reasons?) and also by British High Society, where it is deemed upper class to replace family life by boarding school and considered a sign of nobility to leave home early. So even the present Queen had to part with her first-born and send him to such an institution. None of this is strictly speaking any of my concern. I t only came to my mind when I once again realized how much I gained from the time I spent with my father as a young boy and how little I would have profited from school had he not been there. He actually knew far more than they had to offer, not because he had been forced to study it thirty years earlier, but because he was still interested. If I went into detail here, I should end up telling a long story. Later on, when he had taken up botany and I had virtually devoured The Origin oj Species, our discussions took on a Autobiographical Sketches 175 different character, certainly different from that conveyed at school, where the theory of evolution was still banned from our biology lessons and teachers of religious education were advised to call it heresy. Of course I soon became an ardent follower of Darwinism (and still am today, for that matter), while Father, influenced by his friends, urged caution. The link between natural selection and the survival of the fittest on the one hand and Mendel’s law and de Vries’s theory of mutation on the other had yet to be fully discovered. Even today I don’t know why zoologists have always tended to swear by Darwin, while botanists appear to be rather more reticent. However, one thing we all agreed on - and when I say ‘all’, I particularly remember Hofrat Anton Handlisch, who was a zoologist at the museum of natural history and the one I knew and liked best of all my father’s friends - we were all unanimous in holding that the basis of evolutionary theory was causal rather than finalistic; and that no special laws of nature, such as vis viva, or an entelechy, or a force of orthogenesis, etc., were at \vork in living organisms to abro- gate or to counteract the universal laws of inanimate matter. My religious teacher would not have been happy about this view, but he did not concern me anyway.

Our family was accustomed to travelling in the summer. This not only brightened my life, but also helped whet my intellectual appetite. I remember one visit to England a year before I started intermediate school (Mittelschule) , when I stayed with relatives of my mother at Ramsgate. The long, wide beach was ideally suited for donkey rides and learning to handle a bicycle. The strong tidal changes claimed my full attention. Little bathing huts on wheels were set up along the beach, and a man and his horse were always busy moving these cabins up or down according to the tide. On the Channel I first noticed that one could make out the funnel smoke of distant boats on the horizon long before they themselves appeared, a result of the curvature of the water- surface.

In Leamington I met my great-grandmother at Madeira Villa, and as she was called Russell and the street she lived in was called ‘Russell’, I was convinced it was named after my late great-grandfather. An aunt of my mother’s also lived there with her husband, Alfred Kirk, and six Angora cats. (In later years there were said to be twenty.) In addition she had an ordinary tomcat who would very often come home from his nocturnal adventures in a sad state, so he was given the name Thomas Becket (referring to the Archbishop of Canterbury who was killed in office by order of King Henry II) - not that. this meant a great deal to me then, nor was it very appro- priate. It is thanks to my Aunt Minnie, Mother’s youngest sister, who moved from Leamington to Vienna when I was five, that I learnt to speak fluent English long before I could write in German, let alone English. When I was finally introduced to the spelling and reading of the language I thought I knew so well, I was in for a surprise. It was thanks to my mother that half-days of English practice were launched. I was not too pleased about that at the time. We would walk from the Weiherburg down to the pretty and in those years still quiet little town of Innsbruck together, and Mother would say: ‘Now we are going to speak English to each other the whole way - not another word of German.’ And that is just what we did. I only realized later how much I profited from it to this day. Though forced to leave the country of my birth, I never felt a stranger abroad. I seem to remember visiting Kenilworth and Warwick on our bicycle tours round Leamington. And on the way back to Innsbruck from England I remernber seeing Bruges, Cologne, Coblenz - a steamboat took us up the Rhine - I remember Riidesheim, Frankfurt, Munich, I think; then Innsbruck. I can recall the little boarding house which belonged to Richard Attlmayr.

From there I went to school for the first time, down to St Nikolaus, where I had private tuition, as my parents were afraid I had forgotten my ABC and my sums during the holiday and would fail my entrance exam in the autumn. In later years we nearly always went to the South Tyrol or Carinthia, and sometimes we would go to Venice for a few Autobiographical Sketches 177 days in September. There is no end to the list of beautiful things I was given the chance to see in those days, things that no longer exist, due to the motor car, ‘development’ and new borders. I think few people then, let alone today, experienced such a happy childhood and adolescence as I did, even though I was an only child. Everyone was friendly towards me and we were all on good terms with each other. If only all teachers, including parents, would take to heart the necessity of mutual understanding! We cannot exert any lasting influence over those en trus ted to us wi thou tit. Maybe I ought to say something about my years at university between 19°6 and 19 I 0, as there might not be any chance of doing so later on. I mentioned earlier that Hasenohrl and his carefully conceived four-year course (five hours a week!) influenced me more than anything else. Unfortunately I missed the last year (19 I 0/ I I), as I could no longer postpone my national service. As it turned out this was not quite as unpleasant as I had anticipated, for I was sent to the beautiful old town of Cracow and I also spent a memor- able summer near the Carinthian border (near Malborghet). Apart from Hasenohrl’s, I attended all the other mathemat- ics lectures I could. Gustav Kohn gave his talks on projective geometry. His style, so severe and clear, left a lasting impres- sion. Kohn would alternate from a pure synthetic method one year - without any formulas - to an analytical approach the next. There is in fact no better example for the existence of axiomatic systems. Through him duality in particular turned out to be a breathtaking phenomenon, differing somewhat in two- and three-dimensional geometry. He also proved to us the profound influence of Felix Klein’s group theory on the development of mathematics. The fact that the existence of a fourth harmonic element has to be accepted as an axiom in a two-dimensional structure while it can easily be proved in a three-dimensional was to him the simplest illustration of Goedel’s great theorem. There were so many things I learnt from Kohn which I would never have had the time to learn later on.

I attended Jerusalem’s lectures on Spinoza - a memorable experience for whoever listened to him. He talked about so many things, about Epicurus’ 6 3civato<; OUbEV npo<; l1Jlci<; (‘Death is not man’s enemy’) and his DUbEV 3aUJlu<;E1V (’to wonder at nothing’), which Epicurus always kept in mind when philosophizing. In my first year I also did qualitative chemical analysis, and certainly gained a lot from it. Skraup’s lectures on inorganic chemical analysis were rather good; those on organic chemical analysis, which I read during the summer term, poor in comparison. They could have been ten times as good and still they would hardly have improved my understanding of nucleic acids, enzymes, antibodies and the like. As it was I could only feel my way ahead, led by intuition, which was none the less productive. On 31 July 19 14 my father turned up at my little office in the Boltzmanngasse to break the news that I had been called up. The Predilsattel in Carinthia was to be my first destination. We went off to buy two guns, a small one and a large one. Fortunately I was never forced to use them on either man or animal, and in 1938 during a search of my flat in Graz I handed them over to the good-natured official,just to be sure. A few words about the war itself: my first posting, Predilsat- tel, was uneventful. Once, though, we had a false alarm. Our commanding officer, Captain Reindl, had arranged with confi- dants that in the event of Italian troops advancing up the wide valley towards the lake (Raiblersee), we were to be warned by smoke signals. I t so happened that someone was baking pota- toes or burning weeds just along the border. We were told to man the two watchposts and I was put in charge of the one on the left. We spent ten days up there before someone remem- bered to call us back down. Up there I learnt that springy floorboards (with only a sleeping-bag and blanket) are much more comfortable to sleep on than a solid floor. My other observation was of a different nature, something I never came across before or after. One night the guard on duty woke me up to report that he could see a number of lights moving up the slope opposite us, obviously heading toward our position.

(Incidentally, this part of the mountain (Seekopf) had no paths Autobiographical Sketches 179 at all.) I got out of my sleeping-bag and made my way through the connecting passage to the post to take a closer look. The guard was right about the lights, but they were St Elmo’s fire on the top of our own wire abatis a couple of yards away, and the displacement against the background was only parallactic. This was because the observer himself was moving. When I stepped out of our spacious dug-out at night I would watch these pretty little fires on the tips of the grass that covered the roof. This was the only time I came across the phenomenon. After spending much idle time there I was posted to Fran- zensfeste, then to Krems and then to Komorn. For a short time I had to serve at the front. I joined a small unit first at Gorizia, then at Duino. They were equipped with an odd naval gun. We eventually retired to Sistiana, and from there I was sent to a rather boring but none the less beautiful observation post near Prosecco, 900 feet above Trieste, where we had an even odder gun. My future wife Annemarie came to see me there, and on one occasion Prince Sixtus of Bourbon, the brother of the Empress Zita, visited our positions. He was not in uniform, and later I learnt that he was in fact our enemy as he was serving in the Belgian army. The reason for this was that the French did not allow any member of the Bourbon family to join their army. The aim of his visit at the time was to bring about a separate peace agreement between Austria-Hungary and the Entente Cordiale, which, of course, meant high treason against Ger- many. Unfortunately his plan never materialized. My first encounter with Einstein’s theory of 1916 was at Prosecco. I had so much time at my disposal, yet had great difficulties in understanding it. Nevertheless a number of marginal notes I made then still appear reasonably intelligenL to me even now. As a rule Einstein would present a new theory in an unnecessarily complicated form, and never more so than in 1945, when he introduced the so-called ‘asymmetric’ unitary field theory. But perhaps that is not just characteristic of that great man, but nearly always happens when someone postu- lates a new idea. In the case of the above-mentioned theory Pauli told him there and then that it was unnecessary to introduce the complex quantities, because each of his tensor equations consisted of both a symmetric and a sheer symme- tric part anyway. Only in 1952, in an article he wrote together with Mme B. Kaufman for a volume published to celebrate Louis de Broglie’s sixtieth birthday, did he agree with my much simpler version by ingeniously excluding the so-called ‘strong’ version. This was a very important move indeed. The last year or so of the war I spent as a ‘meteorologist’ first in Vienna, then Villach, then Wiener Neustadt and finally in Vienna again. This was a great asset to me, as I was spared the disastrous retreat of our badly torn front lines. In March/April 1920 Annemarie and I got married. We moved soon after to J ena, where we took furnished lodgings. I was expected to add some up-to-date theoretical physics to Professor Auerbach’s set lectures. We enjoyed the friendship and cordiality of both the Auerbachs, who were Jews, and of my boss Max Wien and his wife (they were anti-Semites by tradition, but bore no personal malice). Being on such good terms with them all was a great help to me. In 1933, the Auerbachs, I am told, saw no means of escape from the oppression and humiliation which Hitler’s taking over (Mach- tergreifung) held in store for them but suicide. Eberhard Buchwald, a young physicist who had just lost his wife, and a couple called Eller with their two little sons were also amongst our friends inJena. Mrs Eller came to see me here in Alpbach last summer (1959), a poor bereaved woman whose three men-folk had lost their lives fighting for a cause they did not believe in. A chronological account of someone’s life is one of the most boring things I can think of. Whether you are recalling incidents of your own life or that of someone else, you will rarely find more than the occasional experience or observation worth recounting - even if the historical order of events seems important to you at the time. That is why I am now going to give a short summary of the periods of my life, so that I can refer to them later without having to watch the chronological order.

The first period ( 1887- 1920) ends with my marrying Annemarie and leaving Germany. I shall call it my first Autobiographical Sketches Viennese Period. The second period (1920-7) I shall call ‘My First Years of Roaming’, as I was taken to J ena, Stuttgart, Breslau and finally to Zurich (in 1921). This period ends with my call to Berlin as Max Planck’s successor. I had discovered wave mechanics during my stay in Arosa in 1925. My paper had been published in 1926. As a result of this I went on a two-month lecturing tour of North America, which prohibition had dried up successfully. The third period (1927-33) was a rather nice one. I shall call it ‘My Teaching and Learning’. It ended with Hitler’s assumption of power, the so-called Machter- greifung, in 1933. While completing the summer term of that year I was already busy sending my belongings to Switzerland. At the end ofJ uly I left Berlin to spend my holidays in the South Tyrol. The South Tyrol had become I talian under the Treaty of St Germain, so it was still accessible to us with our German passports, whereas Austria was not. Prinz Bismarck’s great successor had succeeded in imposing a blockade in Austria which became known as the Tausendmarksperre. (My wife, for instance, could not visit her mother on her seventieth birthday. His Excellency’s authorities did not give her permission). I did not go back to Berlin after the summer, but instead handed in my resignation, which remained unanswered for a long time. In fact they then denied ever having received it, and when they learnt I had been awarded the Nobel Prize for physics, they flatly refused to accept it. The fourth period (1933-9) I shall call ‘My Later Years of Roaming’. As early as spring 1933 F. A. Lindemann (later Lord Cherwell) offered me a ’living’ in Oxford. This was on the occasion of his first visit to Berlin, when I happened to mention my distaste for the present situation. He faithfully kept his word. And so my wife and I took to the road in a little BMW acquired for the occasion. We left Malcesine and via Bergamo, Lecco, St Gotthard, Zurich and then Paris we reached Brussels, where a Solvay Congress was being held. From there we went to Oxford; we did not travel together. Lindemann had already taken the necessary steps to make me a fellow of Magdalen College, though I received the greater part of my pay from ICI. ERWIN SCHRODINGER When, in 1936, I was offered a chair at Edinburgh Univer- sity and another at Graz, I chose the latter, an extremely foolish thing to do. Both the choice and the outcome were unexampled, though the outcome was a lucky one. Of course I was more or less undermined by the Nazis in 1938, but by then I had already accepted a call to Dublin, where de Valera was about to found the Institute for Advanced Studies. Loyalty towards his own university would never have allowed Edinburgh’s E.T. Whittaker, de Valera’s former teacher, to suggest me for the post had I gone to Edinburgh in 1936. As it was, Max Born was appointed in my stead. Dublin proved a hundred times better for me. Not only would the work in Edinburgh have been a great burden to me, but so would the position of enemy alien in Great Britain throughout the war. Our second ’escape’ took us from Graz, via Rome, Geneva and Zurich to Oxford where our dear friends, the Whiteheads, put us up for two months. This time we had to leave our good little BMW, ‘Grauling’, behind, as it would have been too slow, and besides, I no longer possessed a driving licence. The Dublin Institute was not yet ‘ready’, and so my wife, Hilde, Ruth and I went to Belgium in December 1938. First I held lectures (in German!) at the University of Ghent as guest professor; this was for the ‘fondation Franqui-Seminar’. Later on we spent about four months in Lapanne by the sea. It was a lovely time - despite the jellyfish. I t was also the only time I ever came across the phosphorescence of the sea. In Septem- ber 1939, the first month of the Second World War, we left for Dublin via England. With our German passports we were still enemy aliens to the British, but obviously thanks to de Valera’s letters of reference we were granted transit. Perhaps Lindemann pulled a few strings on that occasion too, despite the rather unpleasant encounter we had had a year before. He was after all a very decent man, and I am convinced that as his friend Winston’s advisor in matters of physics he proved invaluable in the defence of Britain during the war. The fifth period (1939-56) I shall call ‘My Long Exile’, but without the bitter associations of the word, as it was a wonderful time. I would never have got to know this remote Autobiographical Sketches and beautiful island otherwise. Nowhere else could we have lived through the Nazi war so untouched by problems that it is almost shameful. I can’t imagine spending seventeen years in Graz ’treading water’, with or without the Nazis, with or without the war. Sometimes we would quietly say amongst ourselves: ‘Wir danken’s unserem Fuhrer’ (‘We owe it to our Fuhrer’) .

The sixth period (19S6-?) I shall call ‘My Late Viennese Period’. As early as 1946 I had been offered an Austrian chair again. When I told de Valera about it he urgently advised me against it, pointing to the unsettled political situation in Central Europe. He was quite right in that respect. But while he was so kindly disposed towards me in many ways, he showed no concern for my wife’s future should anything happen to me. All he could say was that he wasn’t sure what would happen to his wife in such a situation either. So I told them in Vienna that I was keen on going back, but that I wanted to wait for matters to return to normal. I told them that because of the Nazis I had been forced to interrupt my work twice already and start all over again elsewhere; a third time would certainly put an end to it altogether. Looking back, I can see that my decision was right. Poor Austria had been raped and was a sad place to live in those days.

My petition addressed to the Austrian authorities for a pension for my wife as a kind of reparation was in vain in spite of the fact that they seemed keen to make amends. The poverty was too great then (and still is today in 1960, for that matter) to make allowances for certain individuals and deny them to almost all others. Thus I spent ten more years in Dublin, which turned out to be of great value to me. I wrote quite a number of short books in English (published by Cambridge University Press) and continued my studies on the ‘asymmetric’ general theory of gravitation, which appears to be disappointing. And last but not least there were the two successful operations in 1948 and 1949 by Mr Werner, who removed the cataracts from both my eyes. When the time had come, Austria very generously restored me to my former position. I also received a new appointment to Vienna University (extra status), although at my age I could only expect two and a half years in office. lowe all this mainly to my friend Hans Thirring, and to the Minister of Education, Dr Drimmel. At the same time my colleague Robracher successfully pushed the new law for the status of Professor Emeritus and thus also supported my cause.