Wald.

Abraham Wald was a Hungarian mathematician who studied in Austria , emigrated to the U.S. because of Jewish persecution, and eventually found himself working for the The Statistical Research Group during World War II. The SRG was a badass collection of very smart statisticians helping the war effort.

So, here was the problem: American planes were getting shot down. There was some room for heavier armor but not too much room because that makes the planes less maneuverable and fast.

The military came to Wald for the solution.

They also had collected quite a bit of data. They had all the spots where planes had been hit by enemy fire after their return engagements over Europe. It would make sense to fortify those sections of the plane, right? After all, that’s where the majority of enemy fire was going.

Wrong, said Wald.

Those are the planes that have returned. We need to put armor on all the places where we don’t see bullet holes, because it’s those planes that didn’t make it back and thus, it’s those spots that need better armor in order to be able to return.

It really takes a second to think through but makes perfect obvious sense when you do.

There’s an entire article about Wald here but my favorite part was this: “A mathematician is always asking, ‘What assumptions are you making? And are they justified?’”

And that is the crux, isn’t it?

Because, it sure seems that lots of us are spending all kinds of time putting extra armor in the exact spot where we don’t need it. We’re getting heavier and slower and still getting shot down because we’re ignoring the most obvious, yet hidden, truths that require us to ask about our assumptions and their justifications.