Jung, C. G. The Structure and Dynamics of the Psyche. Translated by R. F. C. Hull. London:  Routledge & Kegan Paul; New York,  Pantheon, 1960. pp.  x + 596. (Collected Works 8, Bollingen Series No. 20).

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In fact, in this essay on synchronicity, Jung has really given us not one but three major explanatory principles.

1. Acausal orderedness. Jung regards this as the major category; it would therefore have been more logical to oppose this to the causality principle rather than synchronicity; for Jung himself regards synchronicity as only a special instance of the acausality principle.

2. Synchronicity. This is a phenomenon with the essential quality of meaningfulness. Jung places the accent quite emphatically on this quality when he distinguishes synchronicity or, as he calls it, ‘meaningful coincidence’ from what he calls ‘meaningless chance groupings’.

   Jung ascribes the functioning of synchronicity to the activity of the unconscious psyche. He claims that only the unconscious psyche can have a-priori knowledge, that such knowledge is usually in the form of images and that it is always based on archetypal processes.

3. The ‘psychoid’. Jung describes the psychoid as a property which is common to both matter and psyche and he attributes it to the collective unconscious. Jung considers that such a concept is essential, if one is to account for the interaction between mind and matter. For how, he asks, can there be such interaction unless ‘… psyche touches matter at some point and matter is latent with psyche’ (para. 441).…

The concepts of synchronicity and of historical reality emphasize the fusion of subject and object, and this brings them close, I think, to the idea of non-duality which is basic to Zen philosophy. Jung, the Western scientist, has thus arrived at a point to which the Oriental philosopher attained through speculation and meditation. Yet the Western scientist makes, I think, his own special contribution. For the acknowledgement not only of synchronicity but also of the principle of causality is an acknowledgement that the human mind needs concepts and that experience is possible only when the opposites have differentiated. Only through oppositeness and contrast can