1. It is not incumbent upon the historian of a single doctrine to pass judgment upon the question of the proper position of Ricardo as a general economist, compared with Smith and Malthus. But since, in the following chapter, we shall be led to find much fault with Ricardo’s method of exposition of the theory of value, it is necessary to state at the outset that Ricardo’s writings on value possess the distinctive merit, in contrast with those of Smith and Malthus, that they can be reduced to a whole, essentially self-consistent in its large lines. Self-consistency is not the sole test of truth, and this praise does not signify that Ricardo’s is a correct theory, but the longer one studies Ricardo the more satisfactory does his text become, up to the point where one believes he has obtained a complete understanding of it. On the other hand, it is a task of supreme difficulty to read Ricardo critically. His inconsistencies in the use of terms are most trying. It is remarkable that the final result of his reasoning was on the whole self-consistent. The commentator is inclined to quote Senior with approval when he remarked that Mr. Ricardo “is perhaps the most incorrect writer [_i. e._, in the use of terms] who ever attained philosophical eminence.”[44] The point of greatest weight in the labor theory of value, after the vestibule of the subject has been passed through, is treated with a maladroitness which has made a matter that is not over-difficult in itself very hard to understand. This is the theme of sections IV and V of the chapter on value, and is, indeed, in another guise, the difficulty arising out of the “organic composition of capital,” which, under this name, becomes the main point of theoretical interest in the third volume of Marx’s _Das Kapital_. There is abundant evidence that Ricardo himself considered the theory of value to be a very hard problem, and furthermore that he was not completely satisfied with his own treatment of it. As late as 1823, he wrote to McCulloch: “The difficult subject of value has engaged my thoughts, but without my being able satisfactorily to find my way out of the labyrinth.”[45] Earlier he wrote to the same disciple: “I am not satisfied with the explanation I have given of the principles which regulate value.”[46] Some things have a value which is obviously not regulated by labor cost. Concerning these, Ricardo wrote: “I cannot get over the difficulty of the wine which is kept in the cellar for three or four years [_i. e._, while constantly increasing in exchange value], or that of the oak tree, which perhaps originally had not 2 s. expended on it in the way of labour, and yet comes to be worth £100.”[47]