Like Einstein, Pauli taught at ETH Zurich. In 1945, he was awarded the Nobel Prize in Physics. However, Pauli’s criticism of accepted thinking, and his interest in the non-rational made him a controversial figure.

ETH Zurich professor Ulrich Müller-Herold, a theoretical chemist in the Department of Environmental Sciences, was one of the organizers of conference:

Why does Wolfgang Pauli continue to fascinate in science?

Besides physics, there were sides to Pauli not known even to his assistants and colleagues at ETH Zurich. Those sides were his philosophical ideas and his deep interest in the depth psychology developed by Carl Gustav Jung. These hidden sides are gradually being unveiled through the publication of his huge body of correspondence, which is of growing scientific interest.

What were the highlights of the conference?

For me it would be that the conference addressed one of the basic, unanswered questions of western philosophy, that of the relation of mind and body. This relationship was at the center of Pauli and Jung’s common interests, and so far it has resisted all attempts to be tackled in any scientific way.

At the conference this question was discussed but with new perspective, based on the fundamental distinction between the two types of time: physical and mental time. In contrast to physical time, which only distinguishes between ‘earlier’ or ‘later’, mental time has three tenses: ‘past’, ‘present’ (the Now), and ‘future’.

There was a proposal at the conference to characterize mental time using a particular mathematical symmetry group, the so-called extended affine group. This group has three irreducible unitary representations. It seems that they can be interpreted as the tenses of mental time, which can now be studied as formally as physical time. This approach paves the way for a new scientific effort since it replaces the apparently overly-complex mind/matter problem with a related, though not equivalent, problem.

Wolfgang Pauli was critical of the ‘merely rational’ in science. How well has science followed Pauli in this respect?

Pauli regarded modern science as one-sided. He argued that irrational aspects play a substantial role in science. Dreams, for instance, are often pivotal in scientific discovery, and there are even more manifestations of the irrational. However, in science as a social system, the irrational is suppressed. Pauli was convinced that this repression was not good for science or society. Published material shows that irrational elements played an important role in the work of Oppenheimer, Teller and Sacharov when they developed ’the atomic bomb’: Oppenheimer spoke of “sweet physics” and, in retrospect, Sacharov confessed his fantasies of omnipotence.

IStill inspires scientists of various fields: Wolfgang Pauli. (Photo: nobelprize.org)

What is to be made of the question of mysticism in Pauli’s beliefs?

I would not call that mysticism. One simply has to face everyday reality. Take the moment of creative insight: the German word “Einfall” nicely describes what happens: something ‘falls’ into consciousness; nobody knows where it comes from. Pauli and Jung discussed its origin in terms of archetypical structures of the unconscious. After unconscious ‘breeding’ periods followed by sudden ’Aha’ moments, rational science of course has to take over in order to communicate an idea, to put it into coherent relation with the existing body of scientific knowledge. There is nothing mystical about that.

What were Wolfgang Pauli’s limitations?

If at all, Pauli’s limitations seem to arise from his extreme demands on scientific quality. He published results only if he had arrived at complete physical understanding in combination with a rigorous mathematical exposition. This restrictive attitude extended to his biting criticism, and may have stifled less self-confident colleagues.

Have those limitations hindered his teaching?

Pauli was an excellent teacher in that he constantly produced excellent physicists. He founded a school of theoretical physics in Switzerland that is still influential. Prominent scientists who attended his lectures as students remember that Pauli imparted theoretical insights, which could not be found anywhere else.

In what areas is Pauli’s legacy relevant to science today?

His huge body of correspondence and unpublished manuscripts remain influential in several areas of science and philosophy: concepts of mind-matter relationships; notions of time and process; adaptive mutations and epigenetic inheritance in biological evolution; and the nature of creative insight. Some of Pauli’s formerly heterodox ideas on these subjects are now closer to current scientific research, in particular, Pauli’s criticism of the role of chance in neo-Darwinian concepts of biological evolution. This was the aim of the Pauli conference at Monte Verità: to confront active natural scientists in these fields with Pauli's ideas.

Pauli’s work with Jung also continues to fascinate. A collection of some 400 dreams Pauli recorded during his psychoanalysis, first with Erna Rosenbaum, then with C.G. Jung in the early thirties, will be published in the near future. Jung used about fifty of these dreams in his classic “Psychology and Alchemy” where they play an important role in the exposition of his epoch-making approach. After publication of the complete collection, the time may become ripe for another Pauli conference.