History of economic thought died, Engels completed the second volume of "Das Kapital" from his notes. Marx wrote his magnum opus "Das Kapital" (1867) at the British Museum's library in London. Karl Marx begins with the concept of commodities. Before capitalism, says Marx, production was based on slavery – in ancient Rome for example – then serfdom in the feudal societies of medieval Europe. The current mode of labor exchange has produced an erratic and unstable situation allowing the conditions for revolution. People buy and sell their labor as people buy and sell goods and services. People themselves have become disposable commodities. As Marx
Value product only to the net output of "capitalist" production, not to the valuation of "all" production in a society, part of which may of course not be commercial production at all. The concept is formulated more precisely when Marx considers the reproduction and distribution of the national income (see e.g. his manuscript called "Results of the Immediate [or Direct] Process of Production", available in English in the Pelican edition of "Das Kapital"), and also online; and the last chapters of "Das Kapital" Volume 3). Marx wrote this in 1864, i.e. about 70 years or so before the first comprehensive Gross National