Finger Dice

You and your friends are trapped on a desert island. What better way to pass the time than to play games? But you have no dice! What do you do?

You could whittle some out of coconut, but instead here’s an easy way for a group of people to simulate rolling a six-sided die. I originally laid out this method in Microscope Explorer, but it seems like a useful thing for everyone to have in their toolkit so I’m sharing it here.

  • Each person secretly picks a random number from 1 to 6. Simultaneously hold out one hand pointing that many fingers or make a fist for a 6. Don’t discuss what you are going to vote ahead of time. That’s cheating!
  • Add up the fingers, with each fist counting as a 6.
  • If the total is greater than 6, subtract 6. Keep subtracting 6 until the total is 6 or less.
  • You now have a number from 1 to 6. That’s your result.

You’ll find that you can also quickly eliminate sets of six as you count fingers. Drop fists or group together fingers that add up to six and drop them as you go, so long as there are still more fingers remaining (i.e. don’t go down to zero).

Statistically all results from one to six should be equally likely, regardless of how many people you include. Can you cheat and rig the results? Only if every player cooperates. If even a single player picks randomly, the result is unpredictable, which is pretty solid.

    Ben Robbins | August 29th, 2022 | , , | show 6 comments