Modern systems: close reading
Synchronicity:
meaning, Jung, the odds
Synchronicity is C. G. Jung’s (1875-1961) word for a meaningful coincidence with no causal link; he coined it in a 1929 seminar, used it in public in 1930 and set it out in 1952, with Wolfgang Pauli. His own test on 483 couples came out within chance; statisticians trace much of the force of coincidences to hidden causes, memory and very large numbers.
Synchronicity is C. G. Jung’s (1875-1961) term for a meaningful coincidence: an inner state (a dream, a thought) and an outer event that match in meaning with no causal link. He set it out in 1952, in a book shared with the physicist Wolfgang Pauli (1900-1958).
What does synchronicity mean?
In Jung’s definition, synchronicity is a state of mind and one or more outer events that coincide in time and seem to mirror each other in meaning, while neither causes the other (1955 English edition, p. 36).
Three things must be present: the timing, the missing cause and a meaning the person sees. Plain simultaneity he called “synchronism”. Jung granted that the meaning is “an anthropomorphic interpretation” (p. 95), yet made it the test.
His best-known case: a young woman was telling him a dream of a golden scarab when something tapped at the closed window. He caught a rose-chafer (Cetonia aurata), which he called “the nearest analogy to a golden scarab” in his latitudes, and says nothing like it happened to him before or since (p. 31). The story is his own, undated, and the only account of it is his.
Where does the idea come from? A dated timeline, 1851-1955
The word is Jung’s: he told a private seminar in December 1929 that he had coined it, and first used it in public on 10 May 1930. The question was older: Jung named an 1851 essay by Arthur Schopenhauer (1788-1860) its “godfather” and cited the Viennese biologist Paul Kammerer (1880-1926).
| Year | What happened (record) |
|---|---|
| 1851 | Schopenhauer, essay on “apparent design” in fate: Jung’s “godfather” (1955, p. 16) |
| 1919 | Kammerer, Das Gesetz der Serie, Stuttgart and Berlin (scan) |
| Dec 1929 | Jung tells his seminar on dreams he has coined the word; in 1928 it had only “synchronism” (LoC) |
| 10 May 1930 | Jung’s address for the sinologist Richard Wilhelm, Munich: first public use (1955, p. 52) |
| 1931 | Address printed with The Secret of the Golden Flower: a “synchronistic principle” behind the I Ching |
| 1952 | Naturerklärung und Psyche, Zurich: Rascher, with Pauli (LoC); English 1955 (LoC) |
Kammerer defined a series as a law-like repetition of similar things whose cases, as far as one can tell, share no common cause (1919, p. 36). Jung’s footnote calls the 1930 address his first use; the seminar notes, printed in 1984, show the word five months earlier (J. Cambray, IAAP). We date by the earlier record (why dates first).
Is synchronicity a Hermetic idea?
No ancient Hermetic text uses the word; Jung traced the idea first to Chinese Tao, then to the “sympathy of all things” and correspondences, a picture of a connected cosmos the Hermetic tradition shares: a lineage, not proof.
His chapter on forerunners (1955, pp. 95-122) opens with Lao-tzu and Chuang-tzu, then quotes a tract ascribed to Hippocrates (“all things are in sympathy”), Philo, Plotinus, Pico della Mirandola (1463-1494) and Cornelius Agrippa (1486-1535), for whom “all things are in all” (Cologne, 1533), then Paracelsus, Johannes Kepler (1571-1630) and Leibniz. Pauli’s half of the book studies Kepler’s quarrel with Robert Fludd (1574-1637), who cites Hermes Trismegistus for the world as the image of God (p. 192). “As above, so below”, often attached to synchronicity online, is not in Jung’s list.
Our page on correspondences dates that background: the ancient sources speak of sympathy; “law of correspondence” is the Kybalion’s wording (1908). On the Modern systems line, synchronicity is where the old picture became a psychological claim.
Synchronicity vs coincidence: what is the difference?
Every synchronicity is a coincidence; what makes it synchronicity, for Jung, is the meaning a person sees and his claim that no cause links the two events.
The statisticians Persi Diaconis and Frederick Mosteller (1989) define a coincidence as a surprising concurrence of events, felt to be related, with no apparent cause, close to Jung. Where Jung saw a factor “equal in rank to causality”, they list four ordinary sources:
- A hidden cause nobody has spotted.
- Memory. Hits are remembered, misses are not.
- Loose matching. “Close” counts as “the same”, and many kinds of match would have counted.
- Very large numbers. With enough people and days, something astonishing happens to someone.
How likely was that coincidence? A table of odds
A striking coincidence is usually less rare than it feels, because the fair question is not “what are the odds of this?” but “what are the odds of something like this, to someone, some day?”
| Coincidence | The odds | What to check |
|---|---|---|
| Two people share a birthday | 23 people: even chance; within a day, 14 (D. and M.) | Group size |
| A friend calls as you think of them | Thought weekly, call monthly, same hour: 1 in 9 a year; 20 friends, about 2 a year | Times they did not call |
| The clock shows 11:11 | 30 glances a day: 3% of days; with 8 “special” times, about 1 day in 5 | Which times you count |
| A double lottery win | Better than 1 in 30 somewhere in the US in four months (D. and M.) | To whom, anywhere? |
| A “one in a million” day | 250 a day among 250 million people (D. and M.) | How many people |
| A “sign” in your feed | Not chance: feeds follow what you engage with | What you liked or watched |
Unsourced rows are our arithmetic; use your own numbers. Friend: one call a month over 480 waking hours is 1 in 480 per hour, times 52 thoughts. Clock: one minute in 960 waking minutes.
Is synchronicity real? What the research shows
The experience is real and common, but no study has shown an acausal principle behind it, and Jung’s own statistical test, on the horoscopes of 483 married couples, came out within chance, as he himself accepted.
- Jung, 1952. 483 married couples against unmarried pairings: a mathematician found the peaks mere chance scatter (pp. 64-65), and the top figures fell from 8.1% to 5.6% across batches (p. 76). Jung, putting the odds of that pattern across batches at 1 in 62.5 million, called this chance result “a synchronistic phenomenon” (pp. 82-84).
- Diaconis and Mosteller, 1989. Their four sources “account for much of the force of synchronicity”. Probability models, not an experiment. They summarise Ruma Falk (1989): people find their own coincidences far more surprising than the same ones told of others.
- Johansen and Osman, 2015. A review: noticing coincidences is a by-product of normal causal learning. No new data.
- Rodríguez-Ferreiro and colleagues, 2025. Believers in pseudoscience reported more meaningful coincidences, gave them non-chance causes and, asked to write out random coin tosses, avoided repeats. Correlational; no sample size in the abstract.
- Russo-Netzer and Icekson, 2023. Two adult samples (198 and 440): reading meaning into coincidences went with life satisfaction, partly via optimism. Self-report at one time: it measures a habit, not acausal events.
So you are not imagining the coincidences, and their meaning can matter to you. What the evidence does not support is that the timing was arranged.
Is it a sign? Synchronicity in feeds and chatbots
A coincidence on a screen is often not a coincidence: recommendation feeds show more of what you have just engaged with, so a “sign” after a like, a follow or a long watch usually has a cause.
TikTok says its feed weighs likes, shares, follows and captions, and treats finishing a longer video as a strong signal (June 2020): the hidden cause, built in. Once you notice something, it seems to be everywhere, the “frequency illusion” Arnold Zwicky named in 2005 (Language Log). Ask a chatbot whether it is a sign and it may simply agree: five AI assistants tended to tell users what they wanted to hear (Sharma and colleagues, 2023; see Does AI make things up?). The useful question is who chose what you are seeing: the agency question.
How do you test a coincidence in five minutes? A coincidence log
Write the coincidence down the same day and add the column most journals leave out, how often the same thought or event came without the match: the striking moment becomes a count you can check.
- One line, same day, with date and time, before retelling adds detail.
- Name the match. What exactly lined up? If it was “close”, say so.
- The misses. Last month, how often did the first half come with no second half?
- The base rate. How often does the second half happen anyway?
- A hidden cause? Shared news, a date, your feed.
- One action you would take today even if it was chance.
Example.
12 Nov, 19:40: thought of Ana; she texted ten minutes later.
Match: her, not the words.
Misses: I think of her most days, mostly no text.
Base rate: she texts about twice a month.
Hidden cause: our band announced a tour today.
Today: reply about tickets. I would anyway.
Why it might help. Selective memory (Hintzman, 1978) and added detail (Falk, 1982) inflate coincidences, as Diaconis and Mosteller report; writing at once is meant to limit both, and the misses column restores what confirmation bias drops (Nickerson, 1998). The log itself is untested.
Where it stops. It measures rarity, not meaning; an ordinary coincidence can still move you.
What does this not promise?
Neither Jung’s idea nor the log promises guidance, luck or proof of fate; at most the log shows how rare an event was, and what it means stays your decision.
- Not a decision rule. Do not stake health, money or a relationship on a sign.
- Not a verdict on faith. If a coincidence moved you, that is yours; we neither endorse nor mock it.
- Not a treatment. A reading tool, not therapy.
When to see a doctor. If coincidences start to feel like messages aimed at you, from strangers, television or your feed, keep multiplying and come with poor sleep or fear, see a doctor soon. The US National Institute of Mental Health lists such beliefs and disrupted sleep among signs of psychosis, where early treatment often means better recovery (NIMH).
If you think of harming yourself, call now: 988 (US, Canada, call or text); Samaritans 116 123 (UK, Ireland); elsewhere, findahelpline.com; in danger, your local emergency number.
| Term | Coined by C. G. Jung |
|---|---|
| First public use | 10 May 1930, Munich; seminar, Dec 1929 |
| Main text | 1952, with W. Pauli; English 1955 |
| Definition | Meaningful coincidence, no causal link |
| Older roots | Tao, sympathy, correspondences (Jung’s list) |
| Jung’s own test | 483 couples: within chance |
| Research | Coincidences common; no acausal factor shown |
| Checked | 13 November 2026 |
Fair questions
What is synchronicity in simple terms?
It is C. G. Jung’s word for a meaningful coincidence: something in your mind, such as a dream or a thought, matches an outer event in meaning, with no cause linking them. Jung coined the term in a private seminar by December 1929, used it in public in 1930 and set it out in 1952.
What is the difference between synchronicity and coincidence?
Every synchronicity is a coincidence. Jung kept the word for coincidences that feel meaningful and, he claimed, have no causal link; the statisticians Diaconis and Mosteller (1989) argue that hidden causes, memory, loose matching and very large numbers explain much of that force.
Is synchronicity scientifically proven?
No. In Jung’s own test on the horoscopes of 483 married couples, a mathematician found no figure above chance, though Jung still read the pattern as meaningful; no later study has shown an acausal principle, and research finds that people differ in how readily they notice coincidences and read meaning into them.
How can you tell if a coincidence is a sign?
Meaning cannot be tested, but rarity can: write the coincidence down the same day, count how often the thought came without the match, and look for a hidden cause such as your feed. If it would steer a big decision, decide on other grounds.
Is synchronicity a Hermetic idea?
Not by name. Jung traced it first to Chinese Tao and the I Ching, then to the old idea that all things are in sympathy and correspond, quoting Pico della Mirandola and Agrippa (1533) among others; that background is shared with the Hermetic tradition, but it shows where the idea came from, not that it is true.
Sources & further reading
- C. G. Jung and W. Pauli, Naturerklärung und Psyche (Zurich: Rascher, 1952, LoC); English, The Interpretation of Nature and the Psyche (New York: Pantheon, 1955, LoC). Pages from the 1955 edition; in copyright, quoted in short phrases.
- P. Kammerer, Das Gesetz der Serie (Stuttgart and Berlin, 1919), DNB, Internet Archive (Public Domain Mark); dates, GND. A. Schopenhauer, Parerga und Paralipomena (Berlin, 1851), Internet Archive, record only.
- Pauli and Jung letters: Springer 1992 (LoC); Atom and Archetype, Princeton 2001 (LoC). Records only.
- P. Diaconis and F. Mosteller, JASA 84(408), 1989, 853-861, doi, PDF.
- Abstracts read: R. Falk, Am. J. Psychol. 102(4), 1989, record (finding via Diaconis and Mosteller); Johansen and Osman, 2015, doi; Rodríguez-Ferreiro and colleagues, 2025, doi; Russo-Netzer and Icekson, 2023, doi; Nickerson, 1998, doi.
- Feeds and chatbots: TikTok Newsroom, “How TikTok recommends videos #ForYou”, 18 June 2020; B. Zimmer, “Frequency illusion” in the OED, Language Log, 2019 (Zwicky, 7 August 2005); M. Sharma and 18 others, 2023, arXiv:2310.13548.
- NIMH, “Understanding Psychosis”, read 12 November 2026; crisis lines as on our AI anxiety page.
- C. G. Jung, Dream Analysis, ed. W. McGuire (Princeton, 1984, LoC), pp. 44-45 and 417, as quoted by J. Cambray, IAAP; R. T. Carroll, Skeptic’s Dictionary (2015): the sceptic’s reading, synchronicity as apophenia.