slavery and serfdom—as unjust, that proves that this fact itself is a survival; that other economic facts are established thanks to which the first has become insupportable, intolerable. Behind the formal economic inexactitude may, therefore, be hidden a very real economic content. It would, however, be out of place here to dwell at length on the importance and the history of surplus-value.
We can draw other conclusions from Ricardo's theory of value, and that has been done. The value of commodities is determined by the labor exacted by their production. But it is found that in this wicked world commodities are bought sometimes above, sometimes below, their value, and besides, there is the relation to the variations of competition. As the rate of profit has a tendency to maintain itself at the same level for all capitalists, the price of commodities tends also to sink to the value of labor, through the intermediary of supply and demand. But the rate of profit is calculated upon the total capital employed in an industrial enterprise; on the other hand, in two different branches of industry the annual production may incorporate equal masses of labor, that is to say, present equal values, while, if the wages are at an equal level in these two branches, the capital advanced can be, and often is, doubled or trebled in one or the other branch. Ricardo's law of value, as Ricardo himself has already discovered, is in contradiction to the law of the equality of the rate of profit. If the products of the two branches are sold at their value, the aggregates of profits cannot be equal; but if the rates of profit are equal, the products of the two branches are not sold at their value everywhere and always. We have then, here, a contradiction, an antagonism between two economic laws. The practical solu-
