Isn't it normally referred to as the efficient market hypothesis? You don't have to think investors can consistently beat the market to distrust that hypothesis

Isn't it normally referred to as the efficient market hypothesis? You don't have to think investors can consistently beat the market to distrust that hypothesis, and plenty of economists think it is suspect, e.g. behavioural economists: http://www.economist.com/blogs/freeexchange/2009/08/behavioural_finance_to_the_res http://www.economist.com/blogs/freeexchange/2009/08/behaviou... A belief in an efficient market is far from a consensus among professionals. I personally think it's pretty absurd to claim that markets are efficient given that their behaviour is driven by humans with a lot to gain/lose, and algorithms which are looking for short-term profit, not efficiency, and also given the many acknowledged examples of over-confidence, corruption, bubbles and subsequent crashes over the last few decades.