The Invention of Chess

Impressing the King

Legend has it that the game of chess was invented by Sissa ben Dahir of the court of King Shiram. The king was so impressed with this invention that he promised to give Sissa any reward he wished for.

Choosing a Reward

Being a clever chap, Sissa gave the king a choice. The king could either give him 10,000 rupees, or a payment of wheat based on the 64 square chessboard. To pay Sissa in wheat, the king would need to give him one grain of wheat for the first square, 2 grains of wheat for the second square, 4 for the third, 8 for the forth, and so on. Each square should have double the amount of wheat as the previous square.

Now, the kingdom was known for its wheat production, so King Shiram was more than willing to part with some wheat. He thought Sissa a fool to ask for such an insignificant award.

Gathering the Reward

The gathering of Sissa’s reward began. The king had a couple bags of wheat brought into the throne room and the servants started counting. 1, 2, 4, 8, 16, 32, 64, 128, 256, 512…and soon, the first bag was empty. 2 more bags were required, then 4, then 8. The amount needed was growing out of control! Soon, more grain was required then the kingdom could provide. In fact, the total sum of Sissa’s reward amounts to (2^64)-1. That equals a whopping 18,446,744,073,709,551,615 grains of wheat!!

The Moral of the Story

The king realized that he was the fool, not Sissa. The king had underestimated the power of doubling. The amount might not be so noticeable at first, but it can quickly explode out of control.