Aristotle, in his book on POLITICS, tells the following story about Thales, the Ionian philosopher portrayed above and best known for the theory that water is the essence of all matter. "Thales, so the story goes, because of his poverty was taunted with the uselessness of philosophy; but from his knowledge of astronomy he had observed while it was still winter that there was going to be a large crop of olives, so he raised a small sum of money and paid round deposits for the whole of the olive-presses in Miletus and Chios, which he hired at a low rent as nobody was running him up; and when the season arrived, there was a sudden demand for a number of presses at the same time, and by letting them out on what terms he liked he realised a large sum of money, so proving that it is easy for philosophers to be rich if they choose, but this is not what they care about." Fascinating story. Someone who apparently had the reputation of being what we would call today an 'ab...