The Lesson of Exponential Growth: Rice and the Chess Board

The inventor of chess, Sessa, pleased the current king so much, that he was asked to name his own prize. His request seemed modest. One grain of rice doubled for each square on the board.

"If a chessboard were to have rice placed upon each square such that one grain were placed on the first square, two on the second, four on the third, and so on (doubling the number of grains on each subsequent square), how many grains of wheat would be on the chessboard at the finish?"

On the first half of the board, a total of 4,294,967,295 (2³² − 1) grains of rice, or about 100,000 kg of rice (assuming 25 mg as the mass of one grain of rice) were counted. India's annual rice output is about 1,200,000 times that amount. Not that bad.

The Power of IBM Watson

In 1997 my company, SetFocus, began operations and prior to our first class, we had to outfit a classroom with about 20 PCs. Back then, the latest and greatest was a 166mhz machine for about $1,000.

In an effort to shed further light on the notion of exponential thinking, it occurred to me, 'how does that compare to the IBM Watson computer'?

I also have this theory that all technology ends up at the checkout counter at the supper market ... when might that occur?