The Marxian notion of value is a complex theoretical construct, which replaces the Classical semi-empirical category of “labour expended” with an inherently monetary economic theory: Value discloses a historically specific social relation (the “market economy” or capitalism) which manifests itself in money. The value of a commodity cannot be determined as such, but only through its form of appearance; it cannot be determined in isolation but only in relation with all other commodities in the exchange process. This exchange-value relation is expressed through money, which thus becomes the most general form of appearance of capital. Value is the key notion which deciphers what capital and money is. It does not belong to the world of empirically detectable (and measurable) quantities; only money does. The Marxian monetary theory of value allows the comprehension of the endogeneity and non-neutrality of money, in an analytically superior way than any other contemporary theory: Money is not the representative of a commodity or a formal “symbol of value” (exogenously issued by a certain authority), but the “embodiment” of the capital relation: It is thus created in accordance with the process of expanded reproduction of this relation.