The term “coincidence” covers a wide range of phenomena, from the cosmic (in a total solar eclipse, the disc of the moon and the disc of the sun, by sheer chance, appear to have precisely the same diameter) to the personal and parochial (my granddaughter has the same birthday as my late wife). On the human, experiential, scale, a broad distinction can be drawn between serendipity – timely, but unplanned, discoveries or development of events – and what the 20th-century Lamarckian biologist and coincidence collector Paul Kammerer called seriality, which he defined as “a lawful recurrence of the same or similar things or events … in time and space”.
Jung’s collaboration with Pauli was an unlikely coalition: Jung, the quasi-mystic psychologist, a psychonaut whose deep excursions into his own unconscious mind he deemed the most significant experiences of his life; and Pauli, the hardcore theoretical physicist who was influential in reshaping our understanding of the physical world at its subatomic foundations. Following his mother’s suicide and a brief, unhappy marriage, Pauli suffered a psychological crisis. Even as he was producing his most important work in physics, he was succumbing to bouts of heavy drinking and getting into fights. Whereas Kammerer hypothesised impersonal, acausal factors intersecting with the causal nexus of the universe, Jung’s acausal connecting principle was enmeshed with the psyche, specifically with the archetypes of the collective unconscious. Jung’s archetypes are primordial structures of the mind common to all human beings. Resurrecting an ancient term, he envisioned an unus mundus, a unitary or one world, in which the mental and physical are integrated, and where the archetypes are instrumental in shaping both mind and matter. It’s a bold vision, but where, we are bound to ask, is the evidence for any of this? There is more than a grain of plausibility in the suggestion that archetypal structures have an influence in shaping thought and behaviour. But the entire universe? Pauli aside, the idea of synchronicity received little support from the wider scientific community.
Pauli turned for help to Jung, who happened to live nearby. His therapy involved the recording of dreams, a task at which Pauli proved remarkably adept, being able to remember complex dreams in exquisite detail. Jung also saw an opportunity: Pauli was a willing guide to the arcane realm of subatomic physics; and furthermore, Pauli saw Jung’s theory of synchronicity as a way of approaching some fundamental questions in quantum mechanics – not least the mystery of quantum entanglement, by which subatomic particles may correlate instantaneously, and acausally, at any distance. From their discussions emerged the Pauli-Jung conjecture, a form of double-aspect theory of mind and matter, which viewed the mental and the physical as different aspects of a deeper underlying reality.
It’s a state of mind resembling apophenia – a tendency to perceive meaningful, and usually sinister, links between unrelated events – which is a common prelude to the emergence of psychotic delusions. Individual differences may play a part in the experience of such coincidences. Schizotypy is a dimension of personality characterised by experiences that in some ways echo, in muted form, the symptoms of psychosis, including magical ideation and paranormal belief. There is evidence to suggest that people who score high on measures of schizotypy may also be more prone to experiencing meaningful coincidences and magical thinking. Perhaps schizotypal individuals are also more powerfully affected by coincidence. Someone scoring high on measures of schizotypy would perhaps be more spooked by a death dream than I (a low scorer) was.
I have set naturalism and the supernatural in binary opposition, but perhaps there is a third way. Let’s call it the supranatural stance. This was the position adopted, in different ways, by Kammerer, and by the Swiss psychologist Carl Jung. Arthur Koestler’s The Roots of Coincidence (1972) introduced Kammerer’s work to the English-speaking world and was influential in reviving interest in Jung’s ideas. Kammerer began recording coincidences in 1900, most of them mind-numbingly trivial. For example, he notes that, on 4 November 1910, his brother-in-law attended a concert, and number 9 was both his seat number and the number of his cloakroom ticket. The following day he went to another concert, and his seat and cloakroom ticket numbers were both 21.
I sent the picture to my ex, and asked how she was doing. She didn’t reply, but later that evening called with unsettling news. Zoe, an acquaintance of ours, had that afternoon killed herself. My brain by now was in magical thinking mode, and I said I couldn’t help but link Zoe’s death to the appearance, and death, of the golden beetle. I didn’t believe there was a link, of course, but I felt there might be. There was something else at the back of my mind. In Greek mythology, all that king Midas touched turned to gold. His daughter’s name was Zoe, and she too was turned to gold.
His headstone is easy to locate, festooned as it is with drumsticks and cymbals left as offerings by the many pilgrims who make their way to the shrine from around the world. The grave lies in the shade of a spreading, blue-needled conifer and, to the right, there’s a row of three other graves – so just four graves in total (there is also a small, sandcastle-like monument at the base of the tree trunk, which I discounted for lack of name and dates). The plan was to conduct a self-terminating search. Starting with Bonham’s headstone, and with my notebook in hand, I would inspect the other graves in the row and then the rows behind and in front, working my way methodically around the graveyard, until I found any two matching dates of death, but my mission ended almost as soon as it had begun. I needed to go no further than the four graves (with five occupants) in Bonham’s row. The occupants of the two on the right shared 29 September as their date of death (21 years apart). I wish I could report that the mysterious black dog made an appearance, but it didn’t.
frequency illusion n. a quirk of perception whereby a phenomenon to which one is newly alert suddenly seems ubiquitous.

Van Elk and his colleagues were not the first to signal the unreliability of intuitive judgments of probability as a factor in the perception of coincidence. Various authors before them – such as Stuart Sutherland in his book Irrationality (1992) – have suggested that paranormal beliefs, including the belief that some coincidences are supernatural, arise because of failures of intuitive probability. The so-called birthday problem, a staple of introductory classes in probability theory, reliably exposes the flaws of our intuitions. It asks what is the likelihood that two people will share a birthday in randomly selected groups. Most people are surprised to learn that a gathering of only 23 people is required for the chances of two of them sharing a birthday to exceed 50%. I’d been meaning for some time to try a simple empirical exercise involving “deathdays” to mirror the birthday problem. When I found myself again staying briefly at my parents’ old house, a short drive from Rushock, I decided I would use Bonham’s grave as the starting point for my research, for no reason other than the vague pull of that black dog story.
While some coincidences seem playful, others feel inherently macabre. In 2007, the Guardian journalist John Harris set out on “an intermittent rock-grave odyssey”, visiting the last resting places of revered UK rock musicians. About halfway through, he went to the tiny village of Rushock in Worcestershire to gather thoughts at the headstone of the Led Zeppelin drummer John Bonham, who died at the age of 32 on 25 September 1980, after consuming a prodigious quantity of alcohol. A Guardian photographer had visited the grave a few days earlier to get a picture to accompany the piece. It was, writes Harris, “an icy morning that gave the churchyard the look of a scene from The Omen”, and, fitting with one of the key motifs of that film, the photographer was “spooked by the appearance of an unaccompanied black dog, which urinates on the gravestone and then disappears”. Black Dog (1971) happens to be the title of one of the most iconic songs in the Led Zeppelin catalogue.
Ah, but rose chafers are quite common in the south of England; they are active in warm weather; the balcony opens out on a water meadow (a typical rose chafer habitat); et cetera. And it has since been suggested to me that the beetle was quite likely “playing dead” rather than truly dead. Perhaps, after I’d thrown it back out on to the meadow, there was a “rebirth” of the kind these creatures are said to symbolise.
