Ben Graham once said that

in the short-term the stock market is a voting machine, while in the long-term it is a weighing machine.  "市場是情緒控製的" is only true in a short window, mainly due to news, spin, politics…, but in the long-term stocks will follow fundamentals and reward profits. Market as a whole usually know the profits ahead of time. That's why we think "市場是Efficient" for the long term.