If he Ricardo allowed that when A rises in value relatively to, falls in value relatively to, he cut away the ground on which he rested his grand proposition, that the value of a commodity is ever determined by the labour embodied in it, for if a change in the cost of A alters not only its own value in relation to, for which it is exchanged, but also the value of relatively to that of, though no change has taken place in the quantity of labour to produce, then not only the doctrine falls to the ground which asserts that the quantity of labour bestowed on an article regulates its value, but also that which affirms the cost of an article to regulate its value'