Well, I may have overreacted the first time it happened. I can see that now.  When it happened a second time, it spooked me again, but then I looked into the statistics a little more.

A couple weeks ago, inspired by the chance operation ideas of Cage, Zorn, and Eno, I started a little project in which I throw the I Ching once each day (Chance Operation I). I then use the text of the moving lines as a prompt to produce pictures in various AI image generators (Chance Operation II). From the resulting images, I select my favorites and post them on Instagram along with the readings. Even though the selections of what gets posted and what doesn't are based on my personal preferences and therefore willful, they could be considered Chance Operation III by others, as they may consider my preferences to be arbitrary and capricious.

On both Day One and Day Three of the project, I tossed the 30th hexagram, Li. What are the odds? Sixty-four hexagrams, and I threw Li on two out of three tries. This - getting repeat hexagrams - has happened several times now in the past three weeks.

But then on Day 19 of the project, I threw the exact same line (line six) of a hexagram (Hexagram 28) a second time. Then on Day 21, it happened again - a same line (this time the second) of a hexagram (Hexagram 50) for a second time. 

There are 64 hexagrams in the I Ching and each hexagram has 6 lines for a total of 384 lines. What are the chances of getting the same line twice - not once, but two times - in 21 attempts?   

The Birthday Paradox states that in a set of randomly chosen people, at least one pair will have the same birthday. Despite there being 365 days in a year, it only takes a group of 23 for there to be a 50% chance that two people have the same birthday. For a group of 70, there is a 99.9% chance. This seems counter-intuitive at first but with each additional person in the pool, there is one more potential birthday to be matched and the odds increase exponentially.  

The total number of lines in the I Ching, 384, is roughly the same as the number of days in the year. My I Ching project is in its 21st day, about the same as the number of people (23) needed to have a 50% chance of some pair having the same birthday. So it's not really that surprising that I got my first "paired" I Ching line after only 19 days.

For a 50% chance that not one, but two pairs of people will have the same birthday as each other, a group of 36 people is needed. So my odds of randomly obtaining the same line of the I Ching on two different occasions would be about 50% after around 36 or so days. The fact that it happened to me after only 21 days is a bit surprising, but certainly not impossible.

I should be feeling lucky, but my latest repeat hexagram, 50 (Ting), is The Cauldron, and line four reads, "A leg of the cauldron buckles, spilling the hot meal on the very person you wish to serve. Trust evaporates, and the void is filled with shame and scorn." Misfortune, resignation, shame, and defeat.

Good thing I'm not superstitious.