Two Squares tiles

It's very easy to make this two square tiles by any scrap of plywood you can have around in your garage. Cutting them with around 5 cm per side makes them easy to handle. I gave away the two tablets shown in the picture long ago to a friend that wanted to learn more about I Ching. I've never made another pair (and I don't know if my friend still has these two) but I remember it was an easy and pleasant way to cast hexagrams. An easier way to make them is to replace the mahjong tiles with just their number. I must confess I can't remember exactly what I used (and I retouched the picture below to make them more clear) but there are many instructions on the Internet that show you how transfer inkjet printed graphics to wood.

The image at the top left of this post is the back of the two tiles; on the front side, there is a mahjong tile per side as shown in the picture below:

To cast an hexagam the process is:

1. Spin the two tiles independently and without looking.
2. When you feel it's the right time, stop spinning and join the two tiles along one side.
3. Sum the numbers that are on that side (in the picture above it would be 5+3) and draw a line according the following table:

   6	7	8	9

4. Repeat steps 1-3 other five times drawing lines from the bottom to the top of the hexagram

Probablities

This methods provide lines with the yarrow stalk probabilities. The numbers first tile are 4,5,5,6 while the numbers on the second tile are 2,3,3,3. Summing them up as shown in the following table:

gives the same probabilities of the yarrow stalks method:

Prob(6) = ¹/₁₆ = 6.25%
Prob(8) = ⁷/₁₆ = 43.75%
Prob(7) = ⁵/₁₆ = 31.25%
Prob(9) = ³/₁₆ = 18.75%
Prob(yin) = Prob(yang) = ¹/₂

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