Were the quality and capacity of matter everywhere uniform, and all productive power in man, there would be no interest. The advantage of superior tools might at times be transferred on terms resembling the payment of interest, but such transactions would be irregular and intermittent—the exception, not the rule. For the power of obtaining such returns would not, as now, inhere in the possession of capital, and the advantage of time would operate only in peculiar circumstances. That I, having a thousand dollars, can certainly let it out at interest, does not arise from the fact that there are others, not having a thousand dollars, who will gladly pay me for the use of it, if they can get it no other way; but from the fact that the capital which my thousand dollars represents has the power of yielding an increase to whomsoever has it, even though he be a millionaire. For the price which anything will bring does not depend upon what the buyer would be willing to give rather than go without it, so much as upon what the seller can otherwise get. For instance, a manufacturer who wishes to retire from business has machinery to the value of $100,000. If he cannot, should he sell, take this $100,000 and invest it so that it will yield him interest, it will be immaterial to him, risk being eliminated, whether he obtains the whole price at once or in installments, and if the purchaser has the requisite capital, which we must suppose in order that the transaction may rest on its own merits, it will be immaterial whether he pay at once or after a time. If the purchaser has not the required capital, it may be to his convenience that payments should be delayed, but it would be only in exceptional circumstances that the seller would ask, or the buyer would consent, to pay any premium on this account; nor in such cases would this premium be properly interest. For interest is not properly a payment made for the use of capital, but a return accruing from the increase of capital. If the capital did not yield an increase, the cases would be few and exceptional in which the owner would get a premium. William would soon find out if it did not pay him to give a plank for the privilege of deferring payment on James’ plane. In short, when we come to analyze production we find it to fall into three modes—viz: ADAPTING, or changing natural products either in form or in place so as to fit them for the satisfaction of human desire. GROWING, or utilizing the vital forces of nature, as by raising vegetables or animals. EXCHANGING, or utilizing, so as to add to the general sum of wealth, the higher powers of those natural forces which vary with locality, or of those human forces which vary with situation, occupation, or character. In each of these three modes of production capital may aid labor—or, to speak more precisely, in the first mode capital may aid labor, but is not absolutely necessary; in the others capital must aid labor, or is necessary.