_The Equalization of Final Utilities._--Two dollars spent in adding to his previous stock of other things will do the man in the illustration the same amount of good that he can get from a final barrel of apples, and no more. In the case of goods which are all alike and of which consumers are always glad to use an additional amount, prices tend to adjust themselves in such a way that a final unit of any one which the consumer buys with a dollar is worth just as much to him as a final unit of any other article he buys with that amount. The last dollar paid for apples is as remunerative, in the way of pleasure and benefit secured, as is the last dollar used to improve his wardrobe, to add something to his stock of furniture, to buy tickets to the theater, etc. Apples have, as it were, to compete with clothing, furniture, and amusements for the consumer's favor, and if the vender charges more for them than do the venders of other things having the same power to give pleasure, some of the apples will remain unsold; for though customers will always give as much as they would have to pay for other things of equal final utility, they will not give more. _The Prices of All Increments of Supply Equal._--A consumer always gets a net surplus of benefit from the early increments of the goods he consumes. If the last barrel of apples is worth two dollars,--or, what is the same thing, if the last barrel has in it an amount of utility equal to the final utility of other things that two dollars will buy,--the first barrel has a larger utility; and yet it costs no more than the last one. The sellers of apples, if they expect to dispose of all that they have, must at the outset fix the price at such a point that the very last increment of the supply will successfully compete with other articles for the favor of purchasers. Competition forces them to sell the whole amount so cheaply that the least important part of it may be as important to the purchaser of that part as the corresponding and least important part of the supply of other things. Nothing but a monopoly of the entire available stock would enable them to carry out the auctioning plan and offer the stock piecemeal, so as to get a higher price for the parts offered early. Even then buyers who should perceive the fact that a large part of the stock remained in reserve and that it must ultimately be sold would be able, by delaying their purchases, to get the benefit of a later and lower rate, so that the monopoly itself would be only partially successful in its policy. In the absence of a monopoly venders are compelled to sell all articles of one kind and quality at one price. The man who should fix a higher price on his portion of the supply would be passed by in favor of other sellers who were disposing of their final increments, and his business would quietly drift away from him. _There cannot be two prices for one commodity in the same market_ at the same time. This fact is fundamental.