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.
Warren BuffettThe best business returns are usually achieved by companies that are doing something quite similar today to what they were doing five or ten years ago.
Warren BuffettThe problem with commodities is that you are betting on what someone else would pay for them in six months. The commodity itself isn't going to do anything for you....it is an entirely different game to buy a lump of something and hope that somebody else pays you more for that lump two years from now than it is to buy something that you expect to produce income for you over time.
Warren Buffett