http://libfaqf556m6sqcme7kseel4zehmie6pkpu47bzbqzzaofn5xattfxad.onion/secC2.html
It is rooted in what is termed "marginal productivity" theory. In the words of one of its developers: "If each productive function is paid for according to the amount of its product, then each man get what he himself produces. If he works, he gets what he creates by working; if he provides capital, he gets what his capital produces; and if, further, he renders service by co-ordinating labour and capital, he gets the product that can be separately traced to that...