Earlier this year I had some of my elementary students do the classic how-many-times-can-you-fold-a piece-of-paper-in-half exercise. A three-by-three sticky will get you six folds that creates a very nice little eight-by-eight grid. That’s a little stack of paper 64 thicknesses tall. The thickness of the paper is growing exponentially, and it’s not possible to fold it a seventh time. We found a 30-foot-long piece of adding machine tape would allow seven folds but no more.
When I asked the students how many pieces we would have after 10 or 20 folds, the guesses were predictably low. The mind – and not just (of) elementary students – has a difficult time grasping how quickly things increase when they double with each fold.
If you were able to continue folding, it would be just 20 folds to breach the million mark. In fact, 20 folds gets you 1,028,576 very little imaginary pieces of paper. This is exponential growth. Thirty folds and you’ve got over a billion.
Folding a piece of paper in half is trivial, but it illustrates how many things work. One weed in your yard goes to seed and pretty soon the weeds are everywhere. If it’s money you have invested, doubling is a wonderful thing.
If, however, it’s the spread of a new virus across the globe, then it’s a crisis that requires swift action. At the front end of an exponential curve, the numbers look really small and it’s hard to grasp where things are going. Remember: Twenty folds, if possible, would get you to a million.
The time has come to hit the pause button with force and alacrity. The schools have been closed, social distancing has been added to our vocabulary, and many businesses have locked their doors. To effectively slow down the growth of COVID-19, we need to stop just about everything but the essentials.