1. That they have ground down what are essentially matters of relative quantity and velocity, into individual psychological estimates of satisfaction or aversion; and so have been unable to construct anything with them; just as would happen if one were to grind down bricks into brickdust, and then attempt to build with the dust; and so have confused Psychology and Biology with Political Economy.

2. In not seeing that the wheel of wealth is double-sided, each side keeping pace with the other, they have not been able to connect the phenomena turning up on one side of the wheel with the correlated phenomena on the other; and as no product can be said to be properly on the wheel at all (and so belong to the Science of Political Economy) unless it is being continually produced, sold, and reproduced, the consequence is that not only are they unable to separate what strictly belongs to their problem from what does not, but they are only able to give onesided (and therefore practically false) solutions to all the problems discussed. This is especially seen in their discussions of Value and Interest. 3. But more important still, in not seeing that the wheel is a continuously revolving one, they have fallen into the error (everywhere seen in their treatment of the Distribution of Wealth) of supposing that the complexities of their Science, whose subject-matter is entirely dynamic, can be approached by first separating out the dynamical elements and throwing them away, and then concentrating on the relations of the statical, in the belief that the dynamical complications can be unravelled and woven into the statical, later on; and so have missed the true method of approach, which is to begin with the dynamical relations, and then to add the statical, which, as being merely hindrances or obstructions to the free running of the wheel, do not affect the Science in its essentially dynamical character, - whether they come from outside the wheel altogether as in Politics, or are concealed in its interstices, as in the purely economic exploitations of one industrial class by another.

This latter method, as the reader will remember, is the one which I have been obliged to pursue, as seen in my treatment of the Pure and the Applied. Science of the Wheel at the beginning of this volume. Of the affectation of mathematical diagrams and curves, again, in the statical presentation of the academical Economists, I shall have something to say later on.

Let us begin, then, with Jevons, the most important, perhaps, of all the orthodox economists since Mill, in so far at least as his influence on the still later schools of the academic Political Economy is concerned, - especially his influence on the English School, as represented by Marshall; on the Austrian, by Bohm-Bawerk; and, in a roundabout way, on the American, by Clark and others.

And first, as to his solution of the problem of Value, and the modifications he has introduced into the doctrines of Mill and Ricardo. They, it will be remembered, made the value of an article depend on the labour and capital spent in producing it, any variation from the normal market-price being referable to the temporary fluctuations of supply and demand. Jevons proposed to upset this, and to make Value depend on the mental or bodily satisfaction which people got out of things - their 'utility,' as he called it - and although he admitted that the cost of producing them had something to do with their value, it was neither a definite nor an essential element in it. It might be a 'determining circumstance,' he allowed, but not a 'cause.' And the reasons he gave for this were: - first, that the different kinds of labour were essentially variable, and therefore not reducible to any common denomination for purposes of comparison; - for how, he asks, could you ever possibly determine a priori the relative productive powers of a navvy, a carpenter, an iron-puddler, a schoolmaster, or a barrister? Or, again, what, he asks, have the values of old coins, old china, antiques, pictures by old masters, etc., to do with the cost of their production, - in any proper sense of the term cost? But should you suggest that Value, economically speaking, applies only to things that can be produced and reproduced, - as corn, cotton, iron, etc., - he counters you by pointing to the fact that their values are always fluctuating, and therefore cannot have depended on their cost, which at any rate must have been a definite amount.

And although he afterwards admits that Labour, if never the cause of Value, is in a large proportion of cases the ' determining circumstance,' still when he has to make up his mind which he is going to stick to - Labour, or Utility - after making his amende by recognizing a certain element of truth in Mill and Ricardo, he plumps solidly for his own dogma of 'final utility' as the one on which he is going to hang his subsequent deductions, and throws overboard the labour-cost - like an advocate who, beginning by admitting that there is something plausible in his opponent's arguments, allows them to grow dimmer and dimmer as he proceeds, until they fade out of sight altogether; - and so relegates Labour to the scurvy position of a 'determining circumstance' and not to the dignity of a true 'cause'! Now the worst feature of irresolute Thinkers like Jevons, who have not natural penetration enough to gravitate to the central reality, is that, like a man with a candle groping about among the miscellaneous contents of a cellar, they shift their arguments and observations to adapt them to the particular side of the object against which they happen to collide; and, not seeing the other side, either only feebly believe that it has another side, or are unable to bring the two into relation with each other.