Thirty years ago, Wolfgang Pauli, the great Nobel quantum physicist and professor at the very university sponsoring this conference on occult and scientific mentalities in the Renaissance, published a famous essay entitled “The Influence of Archetypal Ideas on the Scientific Theories of Kepler.” It appeared in a volume entitled The Interpretation of Nature and the Psyche in which Carl Gustav Jung, also a member of this university for many years, wrote a companion essay entitled “Synchronicity: An Acausal Connecting Principle.” Pauli's essay is often cited with great admiration by historians who write about Kepler or Fludd and by writers in the Jungian literature conscious of the respectability bestowed upon their work by the association of Jung with a renowned “hard scientist.” Pauli's historical study is, in all respects, a thoroughly professional historical analysis with scrupulous citation of texts, superior translations checked by the art historian Erwin Panofsky, and succinct interpretations. What is never mentioned by anyone in the history of science literature is the fact that the book appeared under the auspices of the C. G. Jung Institute in Zurich, and that the real subject of Pauli's article was not primarily Kepler as a historical figure but rather Kepler as an illustration of the problematic relationship between the observer and what is observed; or, in the language of Jung's analytic psychology, the relation between archetypal images and sense perception.

Until now, no one has asked publicly why Pauli wrote such an essay, why he encoded his analysis in Jungian terms, and what his relationship to Jung might have been. Nor, surprisingly, has anyone questioned the historical account for evidential accuracy or the terms of the analysis itself.