My Logik der Forschung was surprisingly successful, far beyond Vienna. There were more reviews, in more languages, than there were twenty-five years later of The Logic of Scientific Discovery, and fuller reviews even in English. As a consequence I received many letters from various countries in Europe and many invitations to lecture, including an invitation from Professor Susan Stebbing of Bedford College, London. I came to England in the autumn of 1935 to give two lectures at Bedford College. I had been invited to speak about my own ideas, but I was so deeply impressed by Tarski’s achievements, then completely unknown in England, that I chose them as my topic instead. My first lecture was on “Syntax and Semantics” (Tarski’s semantics) and the second on Tarski’s theory of truth. I believe that it was on this occasion that I first aroused the interest of Professor Joseph Henry Woodger, the biologist and philosopher of biology, in Tarski’s work.162 Altogether I paid in 1935–36 two long visits to England with a very short stay in Vienna between them. I was on leave of absence without pay from my teaching job, while my wife continued to teach, and to earn.
During these visits I gave not only these two lectures at Bedford College, but also three lectures on probability at Imperial College, on an invitation arranged by Hyman Levy, professor of mathematics at Imperial College; and I read two papers in Cambridge (with G. E. Moore present, and on the second occasion C. H. Langford, the American philosopher, who was splendid in the discussion), and one in Oxford, where Freddie Ayer had earlier introduced me to Isaiah Berlin and to Gilbert Ryle. I also read a paper on “The Poverty of Historicism”, in Professor Hayek’s seminar at the London School of Economics and Political Science (L.S.E.). Although Hayek came from Vienna, where he had been a Professor and Director of the Institute for Trade Cycle Research (Konjunk-turforschung), I met him first in the L.S.E.163 Lionel Robbins (now Lord Robbins) was present at the seminar and so was Ernst Gombrich, the art historian. Years later G.L.S. Shackle, the economist, told me that he too had been present.
In Oxford I met Schrödinger, and had long conversations with him. He was very unhappy in Oxford. He had come there from Berlin where he had presided over a seminar for theoretical physics which was probably unique in the history of science: Einstein, von Laue, Planck, and Nernst had been among its regular members. In Oxford he had been very hospitably received. He could not of course expect a seminar of giants; but what he did miss was the passionate interest in theoretical physics, among students and teachers alike. We discussed my statistical interpretation of Heisenberg’s indeterminacy formulae. He was interested, but sceptical, even about the status of quantum mechanics. He gave me some offprints of papers in which he expressed doubts about the Copenhagen interpretation; it is well known that he never became reconciled to it—that is, to Bohr’s “complementarity”. Schrödinger mentioned that he might return to Austria. I tried to dissuade him, because he had made no secret of his anti-Nazi attitude when he left Germany, and this would be held against him if the Nazis should gain power in Austria. But in the late autumn of 1936 he did return. A chair in Graz had become vacant and Hans Thirring, professor of theoretical physics in Vienna, made the suggestion that he should give up his chair in Vienna and go to Graz, so that Schrödinger could take over Thirring’s chair in Vienna. But Schrödinger would have none of this; he went to Graz, where he stayed about eighteen months. After Hitler’s invasion of Austria, Schrödinger and his wife, Annemarie, had a hairbreadth’s escape. She drove their car to a place near to the Italian border, where they abandoned it. Taking only hand luggage they crossed the border. From Rome, where they arrived almost penniless, they managed to telephone De Valera, the Irish Prime Minister (and a mathematician), who happened then to be in Geneva, and De Valera told them to join him there. On the Italian-Swiss border they became suspect to the Italian guards because they had hardly any luggage, and money equivalent to less than one pound. They were taken out of the train, which left the border station without them. In the end they were allowed to take the next train for Switzerland. And that is how Schrödinger became the Senior Professor of the Institute of Advanced Studies in Dublin, which then did not even exist. (There is still no such Institute in Britain.)
One of the experiences which I remember well from my visit in 1936 was when Ayer took me to a meeting of the Aristotelian Society at which Bertrand Russell spoke, perhaps the greatest philosopher since Kant.
Russell was reading a paper on “The Limits of Empiricism”.164 Assuming that empirical knowledge was obtained by induction, and at the same time much impressed by Hume’s criticism of induction, Russell suggested that we had to adopt some Principle of induction which in its turn could not be based on induction. Thus the adoption of this principle marked the limits of empiricism. Now I had in my Grundprobleme, and more briefly in Logik der Forschung, attributed to Kant precisely these arguments, and so it appeared to me that Russell’s position was in this respect identical with Kant’s apriorism.
After the lecture there was a discussion, and Ayer encouraged me to speak. So I said first that I did not believe in induction at all, even though I believed in learning from experience, and in an empiricism without those Kantian limits which Russell proposed. This statement, which I formulated as briefly and as pointedly as I could with the halting English at my disposal, was well received by the audience who, it appears, took it as a joke, and laughed. In my second attempt I suggested that the whole trouble was due to the mistaken assumption that scientific knowledge was a species of knowledge—knowledge in the ordinary sense in which if I know that it is raining it must be true that it is raining, so that knowledge implies truth. But, I said, what we call “scientific knowledge” was hypothetical, and often not true, let alone certainly or probably true (in the sense of the calculus of probability). Again the audience took this for a joke, or a paradox, and they laughed and clapped. I wonder whether there was anybody there who suspected that not only did I seriously hold these views, but that, in due course, they would be widely regarded as commonplace.
It was Woodger who suggested that I answer the advertisement for a teaching position in philosophy in the University of New Zealand (at Canterbury University College, as the present University of Canterbury was then called). Somebody—it may have been Hayek—introduced me to Dr Walter Adams (later Director of the London School of Economics) and to Miss Esther Simpson, who together were running the Academic Assistance Council, which was then trying to help the many refugee scientists from Germany, and had already begun to help some from Austria.
In July, 1936, I left London for Copenhagen—I was seen off by Ernst Gombrich—in order to attend a Congress,165 and to meet Niels Bohr; a meeting I have described in section 18. From Copenhagen I returned to Vienna; travelling through Hitler’s Germany. At the end of November I received a letter from Dr A. C. Ewing, offering me academic hospitality in the name of the Moral Sciences Faculty of Cambridge University, together with a letter of support from Walter Adams of the Academic Assistance Council; shortly after, on Christmas Eve, 1936, I received a cable offering me a lectureship in Canterbury University College, Christchurch, New Zealand. This was a normal position, while the hospitality offered by Cambridge was meant for a refugee. Both my wife and I would have preferred to go to Cambridge, but I thought that this offer of hospitality might be transferable to somebody else. So I accepted the invitation to New Zealand and asked the Academic Assistance Council and Cambridge to invite Fritz Waismann, of the Vienna Circle, in my stead. They agreed to this request.
My wife and I resigned from our school-teaching positions, and within a month we left Vienna for London. After five days in London we sailed for New Zealand, arriving in Christchurch during the first week of March, 1937, just in time for the beginning of the New Zealand academic year.
I felt certain that my help would soon be needed for Austrian refugees from Hitler. But it was another year before Hitler invaded Austria and before the cries for help started. A committee in Christchurch was constituted to obtain permits for refugees to enter New Zealand; and some were rescued from concentration camps and from prison thanks to the energy of Dr R. M. Campbell, of the New Zealand High Commission in London.