The Non Linear Property of Water

Liquid water gets lighter in of heavier, right before it changes into solid ice. If you were predicting the behaviour of water from a theory of thermo dynamics, there is no way you would predict that three degrees cold water would be lighter than four degrees cold water. Without this non linear, non monotonic property of water, life as we know it would hardly exists. Same thing with economics, because money, like water, is non linear.