Saturday, 21 May 2016

Four Coins
Four coins can be used to easily generate hexagram lines with yarrow stalks probabilities.

 This method has been devised by Stuart Anderson and proceeds as follows:

  1. Pick three identical coins and one coin that is notably different from the others 
  2. Throw the four coins;
  3. Look at the single different coin:
    • If it's tail, draw  ;
    • If it's head, draw  ;
  4. Look at the four coins, if among them there are exactly three head, it is a moving line.
  5. Repeat steps 1-4 drawing hexagram lines from bottom to top.


The table below summarizes the possible outcomes of this metods, the results that generate a moving line are highlighted in red.

By counting, it's easy to see that the probabilities are:
Prob(6) = 1/16
Prob(8) = 7/16
Prob(7) = 5/16
Prob(9) = 3/16
Prob(yin) = Prob(yang) = 1/2


  1. I'm the author of this method, and although the original article is gone along with, I have found a new home for a (slightly revised and better formatted) version of the article at Here is a direct link, if you're interested:

  2. Thank you for the link and this article (which brought it to my attention.)