I have, in the fourth chapter, observed how necessary a thing it is to distinguish the two constituent parts of every price; the value, and the profit. Let the number of persons be ever so great, who, upon the sale of a piece of goods, share in the profits; it is still essential, in such enquiries as these, to suppose them distinctly separate from the real value of the commodity; and the best way possible to discover exactly the proportion between the one and the other, is by a scrupulous watchfulness over the balance we are now treating of, as we shall presently see. The value and profits, combined in the price of a manufacture produced by one man, are easily distinguished, by means of the analysis we have laid down in the fourth chapter. As long as any market is _fully_ supplied with this sort of work, and _no more_; those who are employed in it live by their trade, and gain no unreasonable profit: because there is then no violent competition upon one side only, neither between the workmen, nor between those who buy from them, and the balance gently vibrates under the influence of a double competition. This is the representation of a perfect balance. This balance is overturned in four different ways. Either the demand diminishes, and the work remains the same: Or the work diminishes, and the demand remains: Or the demand increases, and the work remains: Or the work increases, and the demand remains. Now each of these four combinations may, or may not, produce a competition upon one side of the contract only. This must be explained. If demand diminishes, and work remains the same, which is the first case, either those who furnish the work will enter into competition, in which case they will hurt each other, and prices will fall below the reasonable standard of the even balance; or they will not enter into competition, and then prices continuing as formerly, the whole demand will be supplied, and the remainder of the work will lie upon hand. This is a symptom of decaying trade. Let us now, on the other hand, suppose demand to increase, and work to remain as before. This example points out no diminution on either side, as was the case before, but an augmentation upon one; and is either a symptom of growing luxury at home, or of an increase in foreign trade. Here the same alternation of circumstances occurs. The demanders will either enter into competition and raise the price of work, or they will enter into no competition; but being determined not to exceed the ordinary standard of the perfect balance, will defer making their provision till another time, or supply themselves in another market; that is to say, the new demand will cease as soon as it is made, for want of a supply.