The most famous legend about the origin of chess is due to the Persians. It tells the story of a legendary king of India (according to the versions, the king is called Balhait/Balhit or Shahram/Shirham) who sought at all costs to deceive his boredom. As a result, he promised an exceptional reward to anyone who could find a way to entertain him.
When the wise Sissa, son of the Brahmin Dahir, presented him with the chess set, the ruler enthusiastically asked Sissa what he wanted in return for this extraordinary gift. Humbly, Sissa asked the prince to place one grain of rice on the first square, two on the second, four on the third, and so on, to fill the chessboard by doubling the amount of grain on each square.
The prince was about to grant Sissa this seemingly modest reward when his advisor explained to him that he had just signed the death of the kingdom because the year’s harvests would not be enough to satisfy what had been requested.
Indeed, on the last square of the chessboard, it would be necessary to deposit 263 grains, that is to say more than nine billion billion grains (9,223,372,036,854,776,000 grains precisely), and to add to it the total of the grains deposited on the previous squares, which makes a total of 264-1, that is to say 18,446,744,073,709,552,000 grains, or approximately 4,1011 tons of husked rice.
Some versions say that Sissa did not ask for anything in return, but that the king insisted, so Sissa decided to mock the king by asking for a reward that he could not give.
Variations of this legend exist, one suggesting that the king agreed on the condition that the wise man count the seeds himself, another claiming that Sissa had his head cut off for such effrontery. Let’s hope the king had a good sense of humor…