Here is epic piece from Warren Buffet from November 22, 1999. Just five months before internet bubble collapsed he explained why he didn't invest in internet technology when everyone said that he was being stupid old fool. http://archive.fortune.com/magazines/fortune/fortune_archive...
> 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.