Today the network of relationships linking the human race to itself and to the rest of the biosphere is so complex that all aspects affect all others to an extraordinary degree. Someone should be studying the whole system, however crudely that has to be done, because no gluing together of partial studies of a complex nonlinear system can give a good idea of the behaviour of the whole.

Murray Gell-Mann in ISSS The Primer Project International Society for the Systems Sciences (ISSS) seminar (12 October - 10 November 1997).