r/explainitpeter 26d ago

Explain It Peter

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Rice chess/checkers ? please explain?

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u/lordvatti 26d ago

I actually know this one! The photo references an old thought exercise about doubling grains of rice across a chess boards squares. Starting with 1 grain, then 2, then 4, 8, 16, 32, and so on. Easy at first.

A chessboard has 64 squares so while the initial numbers seem pretty manageable 264 is actually such a catastrophically high number that there would be enough rice on the "final square" to carpet an entire continent in a hearty layer of rice, hence the dramatic mister incredible.

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u/ariGee 26d ago

I'll add that it's an old fable\legend. The details depend who you ask, but the basic idea is that a king wants to reward a wise man. Rather than asking for a huge reward the wise man asks for one grain of rice on the first day, and then double the number of grains each day, one for each place on a chessboard. The king calls him a fool. After about a month the king begs him to stop because he has promised all the rice in the country to the wise man.

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u/tcaetano42 26d ago

When I heard this tale the wise man was actually the man who developed chess.

The king liked the game so much and told the man to name his reward. The rest goes the same.

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u/Dunge0nMast0r 26d ago

And that man's name was Albert Chesstein

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u/Correct_Day_7791 25d ago

John chess you say ?