Keynes (and Keynesians today) would think of the crisis as resulting from the opposite cause: under-investment relative to the supply of saving – that is, too little consumption or aggregate demand to maintain a full-employment level of investment – which is bound to lead to a collapse of profit expectations.
而凯恩斯（以及如今的凯恩斯主义者）则认为危机来自于一个截然相反的根源：与储蓄供应有关的投资不足——就是消费或者总需求过低，不足以维持一个满足全员就业的投资——而这也必定会导致一场收益预期的崩溃。