By the end of 1927, Sraffa, not yet in his thirties, showed Keynes a system of three linear and homogeneous equations to determine prices in an economy without surplus. We now know that these "first equations" were to be the starting point for his future (1960) book. Considered as such, this...

In the first part of Production of Commodities by Means of Commodities</EM>, four equation systems are introduced&colon; three are drawn up in order to solve the problem of relative prices&semi; the last one is devised to define a suitable standard of prices. The book was published in 1960, but--as we are told...