To understand how we got ourselves into our current economic mess, complicated explanations about derivatives, regulatory failure, and so on are beside the point. The best answer is both ancient and simple: hubris - in this case, that of modern mathematical economics, which claimed to have devised a set of scientific tools that could predict and manage human behavior.
https://prosyn.org/mNjoL21
PRINCETON – To understand how we got ourselves into our current economic mess, complicated explanations about derivatives, regulatory failure, and so on are beside the point. The best answer is both ancient and simple: hubris.