###### On Synchronicity

Suppose I tell you the following story: “I had a young woman patient who, in spite of efforts made on both sides, proved to be psychologically inaccessible. The difficulty lay in the fact that she always knew better about everything. Her excellent education had provided her with a weapon ideally suited to this purpose, namely a highly polished Cartesian rationalism with an impeccably “geometrical” idea of reality. After several fruitless attempts to sweeten her rationalism with a somewhat more human understanding, I had to confine myself to the hope that something unexpected and irrational would turn up, something that would burst the intellectual retort into which she had sealed herself. Well, I was sitting opposite her one day, with my back to the window, listening to her flow of rhetoric. She had an impressive dream the night before, in which someone had given her a golden scarab — a costly piece of jewellery. While she was still telling me this dream, I heard something behind me gently tapping on the window. I turned round and saw that it was a fairly large flying insect that was knocking against the window-pane from outside in the obvious effort to get into the dark room. This seemed to me very strange. I opened the window immediately and caught the insect in the air as it flew in. It was a scarabaeid beetle, or common rose chafer, whose gold-green color most nearly resembles that of a golden scarab. I handed the beetle to my patient with the words, ‘Here is your scarab.’ This experience punctured the desired hole in her rationalism and broke the ice of her intellectual resistance. The treatment could now be continued with satisfactory results.”

Suppose now that I tell you that that is how I discovered synchronicity, an all embracing law governing all phenomena that are not causally connected, yet seem to be “meaningfully connected.” I would then argue that there is no such thing as coincidence when two very unlikely things happen at the same time, and that my principle of “acausal connectedness” is proposed for handling precisely these unlikely coincidences.

If you have a basic familiarity with science and probability, you’ll probably laugh at me and think that I am either joking or crazy. You would invoke your science and say that **scientific principles don’t come out of a single or a few personal observations** that cannot be repeated by fellow scientists. You would invoke your probability and say **rare coincidences can happen** and you don’t need a principle for that. … Yet that single experience – and perhaps a few more – is exactly how Carl Jung “discovered” the all embracing principle of “acausal connectedness.”

###### A hypothetical world of a single activity

Our day-to-day activities are too numerous and complicated to submit to a probability-based calculation of coincidences in an easy and understandable way. But let me take you to a simpler world to see if a principle of “acausal connectedness” is needed. In this world, whose population is completely ignorant of probabilities, there is only one activity: tossing coins. Everybody in this world goes to work only to toss 40 coins using a machine that can toss them 200 times per hour. All they have to do is to see if they get all heads (H) or all tails (T), knowing well that such an outcome is next to impossible.

Now suppose that an office worker is celebrating his birthday in the office and suddenly sees that his machine hits the jackpot! He thinks, “OMG! On my birthday? There must be a connection; a meaningful connection, because there is no such thing as random events.” He discovers the principle of “acausal connection!” Imagine the strength of the principle if the day is not just any birthday, but his 40th birthday – still a not-so-unlikely event!

Looking at the uni-activity world from the outside, and knowing something about probability theory, we can calculate the odds. The probability of getting two Hs or two Ts when you toss two coins is 0.5. This is because two out of the four possible outcomes are two Hs or two Ts. So the probability is 2/(2×2) or 2/4=0.5 (or 50%). If you toss three coins, the probability is 2/(2x2x2), or 2/8=0.25 (or 25%); for 4 coins, the probability of getting all Hs or Ts is 2/(2x2x2x2)=2/16, for 5 coins it is 2/(2x2x2x2x2) or 2/32, and so on. So for 40 coins it is 2 divided by 2 multiplied by itself 40 times. This probability is 0.00000000000182. Very small indeed!