It's true that we need doctors and engineers (I am an R&D engineer) but I am constantly astonished by the number of persons working in R&D or simply sitting behind a computer at large companies, banks or administrations. By first hand in my company I know that many computerized workplaces are pure joke where there are workflows but people still print orders and send them to colleagues by the internal snail mail. I also saw many times scientist writing scientific paper during a meeting on another subject. There are even shops that can write a paper for you if your ideas are not clear, you just have to send them an hugly canvas and they write a paper that will be accepted in most conferences on the topic. So I wonder if someone can kindly point out me academic papers showing that education higher improves the wealth of a nation. In fact I would be happy if someone could find a paper schowing that having a very high percentage of "knowledge workers" actually slow down the economy ;-)