"The change which Ruskin's work made in economic thinking has been so far-reaching that today it is difficult for us to realise the perversity and the power of the economic teaching which he fought... Perhaps the greatest contribution which Ruskin made to political economy was this enlargement of its scope. It was not to be confined to exchange: it was not to ignore the real goodness or badness of men's choices: "The essential work of the political economist", he says in Munera Pulveris, "is to determine what are in reality useful or life-giving things and by what degrees and kinds of labour they are attainable and distributable". The political economists of his time would have stoutly denied that it was their business to determine what things are in reality useful, and many economists would still be of the same opinion. By the economist demand must be taken for granted—whatever it was a demand for. Whether the object demanded was good or evil, would do good or harm was not the economists' business. Ruskin refused to accept this abstraction—for an abstraction it surely is, and by his refusal often saw things to which the professionals were blind."