Risk

In 1953 David van Dantzig created this:

risk = (probability of failure) x (projected cost of damage)

It is now the basis for risk analysis from aerospace to nuclear power.
It seems somehow fitting that the Dutch would create something so simple, so powerful, and so inherently pessimistic. I guess it is only perceived as such because it is utterly rational, and rationality isn't always the barer of smiles, hugs, and flowers.

I look forward to having, hopefully, a new approach to risk revealed to me in future reading (LB...).