(1) In the place of 'normal', 'constituted' value we have exchange value, and accordingly coined money instead of a proper 'paper' or 'labour' currency which would genuinely correspond to the concept of money. The first principle is that all economic goods are products of labour, or, as we might put it, that labour alone is creative. This statement, however, does not imply that the value of the product must always equal the cost of labour, or that, in other words, value is even now measured in terms of labour. The truth is rather 'that this still has not become a _fact_, but is only an _idea_ of political economy'.[239] 'If the value could be constituted in accordance with the labour expended on the product, we might imagine a kind of money which would be, as it were, a leaf torn from the public account-book, a receipt written on the most rubbishy material, on rags, which everyone would receive for the value he has produced, and which he would realise as a voucher for an equivalent part of the national product subsequently under distribution.... If, however, for some reason or another, it is _impossible_ or _not yet possible_ to establish this value, money as such must still retain the value it is designed to liquidate; made of an intrinsically valuable commodity like gold or silver, it has to represent a pledge or pawn of the same value.'[240] 'As soon as capitalist commodity production has come into existence, everything is turned upside down: there can no longer be a constituted value, since it can only be exchange value',[241] and, 'since the value cannot be constituted, money cannot be _purely_ money, it cannot fully conform to its concept'.[242] In an equitable exchange, the exchange value of the products would have to equal the quantity of labour needed for producing them, and an exchange of products would always mean an exchange of equal quantities of labour. Even assuming, however, that everybody produced just those use-values which another person requires, yet, 'since we are here concerned with human discernment and human volition, there must always be for a start a correct calculation, adjustment and allocation of the labour quantities contained in the products for exchange, there must be a _law_ to which the facts will conform'.[243] It is well-known that Rodbertus, in his discovery of 'constituted value', laid great stress on his priority to Proudhon which we shall gladly concede him. Marx, in his _Poverty of Philosophy_, and Engels in his preface to it, have comprehensively shown that this 'concept' is a mere phantom, still used in theory but in practice buried already in England well before Rodbertus' time, that it is but a Utopian distortion of Ricardo's doctrine of value. We therefore need not deal further with this 'music of the future, performed on a toy trumpet'.