will be sent off with ignominy) to the nearest suitable shop to make good the deficiency. How can we speak here with a straight face of the relation between marginal utility and price? These are very pertinent criticisms; but they do not make nearly as much nonsense of the notion of marginal utility as may seem at first. The last point, indeed, serves rather to give it a fresh aspect of much significance. Those of us who do not bother about the price we pay for our ties and collars owe a debt of gratitude, of which we are insufficiently conscious, to the more careful people who do; as well as to the custom which prevails in shops in Western countries (as distinct from the bazaars of the East) of charging as a rule a uniform price to all customers. If _we_ were the only people who bought these things, an enterprising salesman would be able to charge us very much what he chose. He could put up his price, and we would hardly be aware of it. And, as by lowering his price he could not tempt us to buy any more, price reductions would be few and far between. But fortunately there are always some people who do know what the price is, even when they are buying collars and ties; and who will adjust the amount they buy in accordance with the price. It is these worthy people who make the laws of demand work out as we well know they do. It is they who will curtail their consumption if the price has fallen and it is they who constitute the seller's problem, and help to keep down prices for the rest of us. The rest of us--it is well to be quite blunt about it--simply do not count in this connection. We have no cause then to plume ourselves that we have disproved the truth of economic laws when we declare that we seldom weigh the utility of anything against its price. All that this shows is that our actions are too insignificant to be described by economic laws since they exert no appreciable influence on the price of anything. And this in turn shows the extreme importance of grasping clearly the conception of the margin. Just as it is the marginal purchase, so it is the marginal purchaser who matters. It is the man who, before he buys a motor bicycle, weighs the matter up very carefully indeed and only just decides to buy it, whose demand affects the price of motor bicycles. It is the utility which _he_ derives that constitutes the marginal utility, which is roughly measured by the price.