Why Terrible Disasters Are Unlikely

Shane Parrish, from Farnam Street Blog, writes about the mental model of Multiplicative Systems. He uses the example of a basketball player that has everything going for him, but was unsuccessful because of a cocaine habit. We may consider the amount of basketball notoriety he could gain as a multiplicative system. His height could be, say, five points. His raw talent another five. His motivation another five. His drug addiction – zero.

Basketball notoreity = 5 x 5 x 5 x 0 = 0

So our basketball player went nowhere because of his one zero. Yet the multiplicative systems model doesn’t only describe how extraordinary people can lose their careers, but also how disasters are unlikely to be particularly terrible. One simple reason is that it’s hard to get so far to either side of a bell curve. Both terrible and amazing events are unlikely. Of course, a sudden apocalypse is more likely than a sudden appearance of Plato’s Republic.

Still, multiplicative systems can prevent apocalypses from getting too bad. Let’s say a bioterrorist tries to give people Ebola. They will probably go around, giving some people Ebola and a small number may die, giving some others the disease before they perish. Still, Ebola doesn’t spread easily. Perhaps a dozen or so people die. This is bad, but it’s no apocalypse, numbers-wise. Compared to a real apocalypse, it’s basically nothing. Without a better way to spread Ebola, the bioterrorist has been unsuccessful at ending the world. They get five points for Ebola and zero (or maybe 0.0001, as it did kill some people) for the distribution method.

Magnitude of oblivion = 5 x 0 = 0

(I don’t know if terrorists, never mind bioterrorists would want to actually end the world. If I meet one I will ask them and get back to you.)

Let’s try another example, where the terrorist has figured out how to make Ebola airborne. Five points for Slytherin! Not to mention the five points they already had for Ebola.

Magnitude of oblivion = 5 x 5 = 25

In reality, there would be more than two parts to the equation. There would be five points for acquiring the Ebola, five for transporting it safely, five for not getting caught by the authorities, etc. Thankfully, all it takes is a single zero to prevent the worst kind of disaster. Smaller events, such as mass shootings, have fewer variables and lower likelihood of a zero showing up. This is how the bell curve happens. Smaller quantities of evil occur more frequently than larger doses.