Abstract: It was once widely acknowledged in the Marxian literature that Marx’s value theory was not a theory of commodity price but a qualitative (not a quantitative) account of exploitative class relations. This acknowledgement has been stressed by the theoretical failure of Marxian economists in defending Marx’s transformation from value into price. Once its role as a theory of price was reluctantly given up, however, its other role as a theory of exploitation was also bound to collapse. Among others, Roemer (1982), Bowles and Gintis (1981) and Samuelson (1982) have shown that a commodity value can also be determined by the amount of any certain kind of input material (like a peanut or steel theory of value) and to that extent any material power (peanut power or steel power) is no less exploitable than labour power. Roemer (1986) has gone a step further to show that exploitation can be analyzed even with no such (peanut or steel-like) value category, in which Marx’s original notion of exploitation has been debased into a thing not founded on equivalent exchanges but on property relations. In the end Marx’s value theory has been proved redundant in connection with both exploitation and price. But redundancy is recently attributed to the conventionally mistaken homogeneous labour theory of value.2