Eugen von Böhm-Bawerk, Zins (1894)

Böhm-Bawerk’s encyclopedia article moves from the definition of interest through the history and criticism of its explanations to the determination of interest rates. Its central conceptual move is to treat interest as a problem of valuation across time: physical productivity alone cannot explain why the value of output regularly exceeds the cost of producing it.

The opening distinguishes capital interest from land rent, contractual loan interest from returns on an owner’s productive investment, and gross receipts from pure interest. Depreciation, risk premiums, and administrative expenses must be deducted before the income attributable to capital ownership becomes visible. The customary rate on secure, long-term loans supplies an accounting benchmark for separating this income from entrepreneurial profit.

The historical survey shows how practical conflicts generated theoretical questions. Ancient and Christian objections addressed lending, especially distress loans that enriched creditors at poor borrowers’ expense. Defenders justified interest by the productive opportunities available to borrowers, but thereby presupposed the return on productive capital that itself required explanation. Industrialization and socialist criticism shifted attention from creditor and debtor to capitalist and worker. The decisive problem became the persistent surplus of product value over costs.

Böhm-Bawerk organizes explanations into six families: productivity, use, abstinence, capitalist labor, exploitation, and intertemporal valuation. His distinction between technical productivity and a surplus of value governs the assessment:

Zwischen diesem Thatbestand – mehr Wert, als das Kapital selbst hat – und dem früher geschilderten – mehr Produkte, als man ohne Kapital erzeugen könnte – besteht offenbar noch eine Differenz.

English translation: There is plainly still a difference between this state of affairs—more value than the capital itself possesses—and the one described earlier—more products than could be produced without capital.

More abundant output can raise the valuation of productive inputs as well as that of their products; it does not by itself explain a net remainder. Use, abstinence, and labor theories locate an additional service or sacrifice behind that remainder. Exploitation theory instead attributes it to owners’ power to withhold part of labor’s product. Böhm-Bawerk objects that labor-value explanations neglect price differences between goods requiring equal labor but unequal production time, and cannot adequately explain interest from rented consumer durables.

His own account makes the premium on present over future goods the common basis of these different returns. Uncertainty and inadequate provision for future needs combine with the technical advantages of time-consuming production. Present resources enable producers to undertake productive roundabout methods that future resources cannot presently finance.

Im Darlehn empfängt der Schuldner eine Summe gegenwärtiger Güter, verspricht dagegen die Rückzahlung nur in — minderwertigen — künftigen Gütern. Die zwischen beiden bestehende Wertdifferenz muß ausgeglichen werden durch ein gewisses Aufgeld, das auf die minderwertigen künftigen Güter geleistet wird, und dieses Aufgeld ist der Zins.

English translation: In a loan, the debtor receives a sum of present goods, but promises repayment only in future goods—of lower value. The difference in value between the two must be offset by a certain premium paid on the lower-valued future goods, and this premium is interest.

The same reasoning extends to production: inputs derive their value from prospective output, discounted because it becomes available only later. Their maturation into present consumption goods yields the entrepreneur’s interest return. Discounting future services likewise explains why rent from durable goods exceeds amortization. Productivity remains important, but is neither the immediate nor the sole cause of interest.

The final section distinguishes this disputed explanation of interest’s existence from the more widely accepted determinants of its rate. Saving supplies capital; productive opportunities and consumption of capital generate demand. Scarcity allocates capital first to the most profitable uses, while the least profitable investment still required to employ the available stock sets the marginal rate. Accumulation therefore tends to lower interest, although wars and major innovations can reverse the movement. Lower rates may increase labor’s share of national income without reducing capitalists’ absolute receipts.

Competition promotes equalization, but risk, market segmentation, and immobile investments sustain differences. The closing discussion separates monetary liquidity from real capital abundance:

Auch die andauernde Geldfülle kann somit nur vorübergehend auf den Zinsfuß wirken, nämlich nur insolange, als die definitive Folge des Geldüberflusses, die Geldentwertung, sich noch nicht, oder wenigstens noch nicht in voller Stärke, eingestellt hat.

English translation: Thus even a lasting abundance of money can affect the interest rate only temporarily, namely only so long as the ultimate consequence of the monetary surplus, monetary depreciation, has not yet appeared, or at least not at its full strength.

As prices adjust, additional money ceases to represent additional real lending capacity. The article’s significance lies in connecting temporal valuation, marginal investment, and distribution while distinguishing durable real determinants from short-lived monetary movements.