A prediction about the direction of the stock market tells you nothing about where stocks are headed, but a whole lot about the person doing the predicting.
For some reason, people take their cues from price action rather than from values. What doesn't work is when you start doing things that you don't understand or because they worked last week for somebody else. The dumbest reason in the world to buy a stock is because it's going up.
Investors making purchases in an overheated market need to recognize that it may often take an extended period for the value of even an outstanding company to catch up with the price they paid.
The key to investing is not assessing how much an industry is going to affect society, or how much it will grow, but rather determining the competitive advantage of any given company and, above all, the durability of that advantage.
Only those who will be sellers of equities in the near future should be happy at seeing stocks rise. Prospective purchasers should much prefer sinking prices.