Reminds me of that old joke: Two economists are leaving a lecture. One says, "Hey, there's a $100 bill on the floor!" The other replies without looking down, "C

Reminds me of that old joke: Two economists are leaving a lecture. One says, "Hey, there's a $100 bill on the floor!" The other replies without looking down, "Can't be. If there were, someone would have picked it up." The market can be inefficient. It's a construct of society and society can set some nonsensical rules. Heck, the market can be inefficient even under simple rules. It's easy to construct dynamical systems with different phases, some with equilibria and some without. Most economic analysis -- that whole supply/demand thing -- assumes an equilibrium to make the math easier.