James Altucher thinks
The Dow is going to 20,000 within the 12 to 18 months. However, he doesn't think people should buy stocks. He thinks it is far too difficult for most people. He also thinks it is mostly a scam and says he would "never ever trust any number that comes out on a 10Q, no matter how GAAP compliant it is."
His advice for those who insist on buying stocks is to buy an index fund and hold on to it. He also says wait for another crash like 2008 and buy a big basket of funds and hold on to them. Take a look: