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The Predisposition to Notice Similarities and Coincidences

How the meanings of coincidences help to explain them.

Key points

  • The synchronicity principle, according to Jung, is an acausal connecting principle.
  • Of the four meanings in a meaningful coincidence, the recognition of similarities between the incidents is fundamental to the explanation.
  • Individual variations in the predisposition to see similarities appears to be a parsimonious explanation for meaningful coincidences.

Psychology, rather than physics, may provide the most efficient explanation for synchronicity.

When Carl Jung (1972) introduced the term synchronicity to the Western World, it was as the synchronicity principle, an acausal connecting principle, which was intended to explain meaningful coincidences. By “acausal” Jung seemed to suggest that the standard view of cause and effect did not govern the occurrence of meaningful coincidences, rather that their shared meaning “acausally” connected the incidents of the coincidence. Jung proposed that the incidents of a meaningful coincidence were linked through a “constellated” or activated archetype coming from a realm beyond cause and effect, which he called “unus mundus”, Latin for one world.

Many additional explanations for meaningful coincidences have followed. Jung, through his work with Nobel Prize laureate Wolfgang Pauli, and many subsequent theoreticians have proposed quantum mechanics to explain meaningful coincidences. Many others insist that chance provides the optimal explanation.

The Four Meanings in a Meaningful Coincidence

Jung scholar Roderick Main (2014) described four meanings in each meaningful coincidence.

  1. Parallel Content: Two or more elements of the coincidence have a semantic-symbolic meaning in common.
  2. Emotional Charge: Coincidences usually provoke surprise, wonder, curiosity, or interest. Emotional charge creates a feeling of significance and meaningfulness.
  3. Explanation: The emotional charge of coincidences commonly triggers the question, “What are the odds?” which implies, “What does this mean about how things happen?”
  4. Use: Coincidences often trigger the question, “What does this mean about me and my future?”

The emotional charge tends to drive attention toward explanation and use. Less attention is directly paid to the semantic-symbolic meanings. Yet without the unlikely shared semantic-symbolic connection between the incidents, the surprise would not take place.

It takes a mind to recognize the shared meanings in the incidents of the coincidence. Usually, the similarities are so self-evident that stepping back to acknowledge the recognition of the similarity seems unnecessary. However, in theorizing about how coincidences happen, we need to acknowledge the fundamental triggering event as the rapid recognition of a shared semantic-symbolic meaning in the elements of each incident. People vary in their predisposition to see matches like this which relies upon their predisposition to notice similarity.

The variability in the perception of similarity

Some coincidences become meaningful through the exact matching of symbolic-semantic meanings. Numbers or words match meaningfully by being exactly the same number or word. However, similarity judgments can be stretched so that somewhat the same becomes equivalent to being the same. For example, some people find birthdays that are separated by a few days almost equivalent to having the same birthday. For some, the difference of a few days triggers an emotional charge while for others, a few days separation makes the pairing a non-coincidence. The degree of similarity becomes subjective.

In another example, maybe the person was thinking of a song, "Hey Jude" and it started playing on the radio, an exact match. Or maybe the person was thinking of "Hey Jude" but another Beatles song started playing instead: a degree of similarity but not an exact match. The greater the perceived similarity between the incidents, the higher the emotional charge.

Computer programs are being developed to measure similarities for applications among objects and other data sets. These programs may one day provide a way to objectify similarity. Until then the judgment of similarity will vary with the subjective predispositions of the person noticing them. The desire to see similarity drives the discovery of similarity.

The need to find similarity

Jung’s "scarab coincidence" illustrates how the need to find the similarity drives a person to find it. Jung needed something startling to break the iron cauldron of his patient’s resistance. She reported a dream of a scarab ring. Jung, perhaps knowing that scarab-like beetles were flying around Zurich seeking roses, heard a tapping sound on glass and went to his window. He grasped a rose chafer beetle and thrust it into the view of his patient. “Here is your scarab!” In this way, Jung forced the similarity into an exact match. It was not an actual scarab but it did resemble one.

According to Jung, the patient's surprise at the apparent match broke her rigid views of reality and of herself. She became more open to Jung’s attempts to help her change.

The primacy of mind

Jung seems to have been partially correct in suggesting that meaning acausally connects two incidents, thereby creating meaningful coincidences. Having a human mind match the similarity between two incidents could be considered “acausal”. While the constellation of an archetype remains a speculative possibility, the psychology of the predisposition to find similarities rests on a stronger explanatory foundation. Without a mind recognizing the meaning shared by the two incidents, there would be no meaningful coincidence.


Jung, CG (1972) Synchronicity. Princeton, NJ: Princeton University Press.

(Roderick M (2014), “Synchronicity and the Problem of Meaning in Science,” in The Pauli-Jung Conjecture and Its Impact Today, ed. Harald Atmanspacher and Christopher A.Fuchs (UK: Imprint Academic, 223–24