are willing to pay for it", like with how any item is priced. So long as people keep thinking stocks will go up, they'll keep buying and the price will go up.

At some point, some large trader, or some overly automated computer program will give a "Sell" order and other large players and BOTS will then also sell in order to "Take Profits" as it plummets....as it plummets for no better reason than the reason it's driving so high.

The real key is either being one of the big guys (Most of us on this board are not), or having a hedge strategy of some sort.

Yes, there is some sort of fundamental value in the market. Some figure that all those companies are actually worth, but what we're seeing for the past few years is based on optimism, not necessarily math.