The Greater Fool theory is an at least somewhat formal concept, see https://en.wikipedia.org/wiki/Greater_fool_theory https://en.wikipedia.org/wiki/Greater_fool

The Greater Fool theory is an at least somewhat formal concept, see https://en.wikipedia.org/wiki/Greater_fool_theory https://en.wikipedia.org/wiki/Greater_fool_theory for a start. I find it to have a lot of explanatory value.