The "efficient market theory" theorizes that it is impossible to beat the market because markets are so efficient. This is laughable, and is usually espoused by economists or unsuccessful traders. Markets are not at all efficient. If they were, then volatility would be a constant...and would cease to exist. Prices would simply find the "correct" price, and no subsequent trading would occur. Trends, reversals, breakouts, and various other patterns prove that the market is NOT efficient. The market does indeed take all that is known and theorized into account. But this is not an efficient process - it is an ongoing and dynamic process. If you think markets are "efficient", then get a real job teaching economic theory at a prestigious university to students who don't know any better. But if you want to make money, then understand that markets are not efficient...and start exploiting the inefficiencies. These videos should help you get started.