Physics and Metaphysics

By ARTHUR KOESTLER

There exists a type of phenomenon, even more mysterious than telepathy or precognition, which has puzzled man since the dawn of mythology: the seemingly accidental meeting of two unrelated causal chains in a coincidental event which appears both highly improbable and highly significant. Any theory which attempts to take such phenomena seriously must necessarily involve an even more radical break with our traditional categories of reasoning than the pronunciamentos of Einstein, Heisenberg or Feynman. It is certainly no coincidence that it was Wolfgang Pauli, discoverer of the Exclusion Principle, who collaborated with C. G. Jung on the latter's famous essay: 'Synchronicity: An Acausal Connecting Principle'. Jung coined the term 'synchronicity' for 'the simultaneous occurrence of two or more meaningfully but not causally connected events'; and he claimed that the acausal factor behind such events is to be regarded as 'equal in rank to causality as a principle of explanation'.

'I have often come up against the phenomena in question,' Jung wrote, '... and could convince myself how much these inner experiences meant to my patients. In most cases they were things which people do not talk about for fear of exposing themselves to thoughtless ridicule. I was amazed to see how many people have had experiences of this kind and how carefully the secret was guarded.'

Apparently the Swiss are more secretive by nature than the British, for, ever since I wrote The Roots of Coincidence I have been inundated with coincidences in readers' letters. The most revealing among these were written by people who started by solemnly affirming that to attribute significance to coincidences is sheer nonsense, yet could not resist the urge to tell their own favourite believe-it-or-not story. Could it be that inside every hard-nosed sceptic there is a soft-nosed mystic crying to be let out?

Readers who share an interest in the collecting of coincidences will find a fair selection in The Challenge of Chance. While working through this vast amount of material, some distinct patterns began to emerge, although they often overlapped, while in other cases it seemed doubtful whether some event with astronomical odds aginst chance should be interpreted as a manifestation of 'classical' ESP or in terms of acausal 'synchronicity'. Thus in the library type of cases, you search for an elusive reference, open a fat volume at random, and there it is. In the deus ex machina type of episodes there is a seemingly providential interposition just in the nick of time to solve a problem, or avert a disaster, of fulfil a premonition. It is interesting to note that this intercession occurs indiscriminately on tragic or trivial occasions. A sub-category in this group is the seemingly miraculous recovery of lost property, usually of sentimental, not monetary value. In the poltergeist cases emotional tensions (usually in unstable adolescents) coincide with gross physical happenings -- again regardless whether the effect is dramatic or grotesque. Among the most frequent 'convergent' or 'confluential' events (as one may call this type of coincidence) are unlikely encounters, although many of these might seem to be induced by ESP. Worst of all from a rational point of view are the clusterings of names, numbers, addresses and dates. Lastly, there is a wealth of well-authenticated cases of premonitions or warnings of impending disasters -- but here it is particularly difficult to make a distinction between ESP and synchronicity, or 'confluential events'.

Even more frustating is the attempt to draw a line between significant coincidences, which seem to be contrived by some unknown agency beyond physical causation, and trivial coincidences due to chance alone. For any such attempt must invoke the laws of probability, which are full of pitfalls -- as we shall presently see.