'You know that all economists since Adam Smith already divided the value of the product into wage of labour, rent, and capital profit, that it is therefore not a new idea to ground the incomes of the various classes, and especially the various items of the rent, in a division of the product. But the economists at once go off the track. All of them, not even excepting Ricardo's school, make the mistake, first, not to recognise that the aggregate product, the finished good, the national product as a whole, is an entity in which workers, landowners, and capitalists all share, but conceiving the division of the unfinished product to be of one kind shared among three partners, and that of the manufactured product as of another kind again, shared between only two partners. For these theories both the unfinished product and the manufactured product constitute as such separate items of revenue. Secondly,--though both Sismondi and Ricardo are free from this particular error--they regard the natural fact that labour cannot produce goods without material help, i.e. without the land, as an economic fact, and take the social fact for a primary datum that capital as understood to-day is required by the division of labour. Thus they set up the fiction of a fundamental economic relationship on which they base also for the shares of the various owners, ground rent springing from the contribution of the land lent by the owner to production, capital profits from the contribution of capital employed by the capitalist to this end, and the wages finally from labour's contribution, seeing that there are separate owners of land, capital, and labour in the society. Say's school, elaborating on this mistake with much ingenuity, even invented the concept of productive service of land, capital, and labour in conformity with the shares in the product of their respective owners, so as to explain these shares as the result of productive service.--Thirdly, they are caught up in the ultimate folly of deriving the wage of labour and the items of rent from the value of the product, the value of the product in turn being derived from the wage of labour and the items of rent, so that the one is made to depend on the other and _vice versa_. This absurdity is quite unmistakable when some of these authors attempt to expound "The Influence of Rent Upon Production Prices" and "The Influence of Production Prices Upon Rent" in two consecutive chapters.'[266] Yet for all these excellent critical comments--the last, particularly acute, actually does to some extent anticipate Marx's criticism of this point in _Capital_, volume ii--Rodbertus calmly falls in with the fundamental blunder of the classical school and its vulgar followers: to ignore altogether that part of the value of the aggregate product which is needed to replace the constant capital of the society. This way it was easier for him to keep up the singular fight against the 'declining wage rate'.