IAR: Influence and Meaning of Phrase

The Wheat on the Chessboard by Liz Huyck

1 Long ago in India, there was a wise mathematician called Sessa. He invented a new game to amuse his friend, the king. He called it “chess.” The king loved chess and told Sessa to name anything he liked as his reward. Anything! The king enjoyed boasting of his limitless wealth. But instead of gold, jewels, or elephants, after much thought Sessa told the king that he wished only some grains of wheat.

2 “What?!?” exclaimed the king, greatly astonished.

3 “I am a simple man,” replied Sessa, “and my wants are few. But since you enjoy my chessboard so much, give me a single grain of wheat on the first square, two grains on the second square, four for the third, and so on. For each square double the last, as each day of play doubles our delight. That will mean more to me than all the riches in the world.”

4 “Very well!” said the king, a little irritated, thinking that Sessa was mocking him. “If wheat is all he wants,” he told his treasurer, “give it to him!”

5 The first day, the treasurer presented Sessa with a single grain of wheat, to the huge amusement of the court.

6 The second day, he got two, on a little cushion. The great lords roared with laughter. But Sessa kept his thoughts to himself.

7 On the ninth day, Sessa received 256 grains, enough to make a small handful. But the very next day, he had two handfuls. It took Sessa 16 days to get enough wheat to fill a large bag. But only one more day to get two bags. The day after, he had four bags.

8 The courtiers stopped laughing and started whispering.

9 By the end of the month, wagons filled with grain were rumbling toward Sessa’s house, and the treasurer began to look worried. Quaking in his boots, he went to see the king.

10 “Highness!” he trembled. “Please look over my calculations, but I don’t think they are in error. By his simple doubling, Sessa has now collected nearly all our stores of wheat! What shall we do? If we continue at this rate the treasury will soon be empty, and I doubt there is enough wheat in the entire world to pay him!”

11 “Impossible!” said the king. But he checked and double-checked the sums, and there was no doubt. In horror, he saw that by square 64, he would owe Sessa a total of 18,446,744,073,709,551,615 grains of wheat!

12 He could not even imagine so many grains—they would make a pile of wheat larger than the tallest mountain. That much wheat could not be gathered in all of India for the next 2,000 years!

13 There was nothing for the king to do but call Sessa, and take back his boasts of limitless wealth.

14 “Sire!” Sessa replied. “Say no more. I am happy with what I have already—I forgive you the second half of the chessboard.”

15 With that, the king and Sessa remained the best of friends and enjoyed many games of chess together. And the clever Sessa got the real reward he had wanted all along—a wiser and more mathematical king.