The archive.

Why do ordinary disturbances in a market economy swell into cumulative waves of boom and slump rather than dying away? Commissioned by the League of Nations to survey the whole field, Haberler refuses every single-cause answer — money alone, saving alone, technology alone, psychology alone — and instead tests each theory for logical consistency and mutual compatibility. He weighs Hawtrey's purely monetary account against the over-investment theories of Hayek, Mises and Spiethoff, distinguishes vertical from horizontal maladjustment, and shows that the acceleration principle and over-investment theory are complementary rather than rival explanations. His synthesis treats prosperity and depression as phases of one unstable adjustment mechanism, in which credit, forced saving, inventories and confidence magnify change and then reverse it.

Deflation in the sense of a gradual decrease in the total demand for goods in terms of money plays an essential rôle in the contraction process.

An equation can look like a law of cause and effect while stating only an identity — and that, in this early critique, is the charge laid against Schumpeter's monetary formula E = MU = Σpm. Haberler shows that its right-hand side merely restates money income as the sum of prices times quantities consumed, while its left-hand side reduces velocity to the number of purchases each coin intermediates; the whole is a tautology, not an explanation. From this he presses on to the larger quarry, the "objective exchange value of money," which he dissolves into ordinary price relations and denies any existence as a measurable social magnitude. Against Wieser and Anderson he insists that value theory needs only two concepts, subjective value and price, anticipating what he would later call the microfoundation of macroeconomics.

The problem of the value of money is a sham problem!

Everyone says prices have risen or money has lost purchasing power, yet no single formula makes such statements exactly measurable — the obstacle, Haberler contends, is not missing data but the vagueness of the concept being measured. Steering between naive faith in index arithmetic and total skepticism, the book first works through the whole apparatus of index theory — arithmetic, harmonic and geometric means, Laspeyres, Paasche, Fisher's "ideal" formula, the circular and reversal tests — to show that formal criteria alone can never fix economic meaning. Only indices traceable to the money cost of one definite bundle of goods are intelligible. Grounding the argument in subjective value and methodological individualism, he concludes that a price level exists only relative to a person or group: there is no objective, supra-personal purchasing power of money to be found.

Das volkswirtschaftliche Preisniveau — ein statistischer Zufall.

English translation: “The economy-wide price level — a statistical accident.”

Comparative advantage, not absolute superiority, is what makes trade pay — a country gains by exporting where its disadvantage is least and importing where it is greatest, even against a rival more efficient at everything. This essay rebuilds that classical theorem on firmer ground, replacing Ricardo's labour theory of value with opportunity cost: the real cost of more of one good is the quantity of another forgone along a substitution curve. Haberler then extends the argument from two goods to many, ranking commodities along a shifting export-import margin set by wages, exchange rates and the balance of payments. He turns the framework against the case for retaliatory tariffs and against protectionist appeals to immobile capital, arguing that idle plant and written-down assets are private losses, not proof of national waste.

Unilateral free trade is thus—tactical considerations aside—thoroughly desirable and preferable to a generalized tariff regimen.

Haberler delivered this lecture with the Depression as backdrop, but treats panics, bank failures and crashes as secondary drama; the real object of explanation is the recurrent rhythm of expansion and contraction in business activity. Money is a necessary condition of the cycle, though not in the crude quantity-theory sense: stable prices in the 1920s, he argues, concealed a "relative inflation" in which credit expansion masked the fall that rising productivity should have produced. The decisive shift is from the level of prices to the vertical structure of production. When bank credit pushes the market rate of interest below the rate warranted by voluntary saving, entrepreneurs lengthen production into more roundabout, capital-intensive projects that consumers have not chosen to fund — a maladjustment that the depression, painfully, corrects. Reflation aimed merely at purchasing power risks reviving the very disproportions that need liquidating.

The fundamental appearance of the business cycle is a wavelike movement of business activity

Here in the English translation of Haberler's 1933 Der internationale Handel, the whole of foreign trade is folded into general price theory: exchange rates are prices formed by supply and demand, balances of payments are not autonomous magnitudes, and comparative advantage is rebuilt on opportunity cost rather than the labour theory of value. The treatise runs from the foreign-exchange market and the gold standard through the transfer problem — with extended treatment of German reparations and the Keynes-Ohlin controversy — to a systematic anatomy of commercial policy: tariffs, dumping, cartels, infant-industry claims and quotas. Throughout, protection is judged by its hidden diversion of resources and its costs to consumers and exporters, not by the visible survival of sheltered industries. Haberler reserves his sharpest hostility for quantitative restrictions, which suppress the price mechanism more arbitrarily than any duty.

It is the increase and not the reduction of duties which is the real economic burden!

When a household buys a car on monthly instalments, does that credit drive the business cycle or merely ride it? This National Bureau study, completed as Regulation W brought consumer credit under wartime control, argues firmly for the second view. Haberler defines instalment credit narrowly — scheduled repayment, finance charge, short maturity, a negotiable instrument — and shifts attention from the stock of debt outstanding to the flow of net credit change, the excess of new lending over repayments, which he takes as its direct contribution to effective demand. Durable-goods purchases, especially automobiles, make that flow cyclically volatile and, through the acceleration principle formalized in Samuelson's appendix, magnify swings in output. Yet credit follows income rather than leading it; between the oversaving arguments of Keynes and Hansen and the Austrian warnings of Hayek and Mises, Haberler places credit as amplifier, not motor.

The dog wags the tail and not the tail the dog.

A devalued currency may pull the exchange market back toward balance or drive it further from it, and telling the two cases apart is the whole problem here. Haberler builds a static two-country skeleton, deriving the demand and supply of foreign currency from underlying import and export schedules and defining stability by how a deficit responds to a falling exchange rate. A negatively inclined supply curve of foreign exchange, he shows, can make depreciation worsen the very deficit it was meant to cure. Recasting the Marshall-Lerner condition as a special case of a broader exchange-market stability rule, he insists that currency-market curves must never be confused with the commodity curves beneath them, and resists the 'elasticity pessimism' of postwar dollar-scarcity debates.

But the free price mechanism could not achieve that result; it would drive the exchange rate in the wrong direction.

Rebuilding a scholarly discipline after a world war is partly a matter of statutes, dues, and committee votes — and this report captures economics doing exactly that. Writing for the American Economic Association, Haberler argues for joining the newly forming International Economic Association, whose design meets the conditions Princeton had set: a modest structure resting on existing national bodies, financed but not governed by UNESCO, and cheap to support at $200 in annual dues. He recounts the April 1949 Paris meeting, the draft statutes reviewed paragraph by paragraph, and the interim slate of officers awaiting the Council's confirmation. Behind the procedural surface lies a real transition: economics reconstituting itself as an organized international profession through deliberately limited cooperation.

In accordance with the Interim Arrangements provided in the Draft Statutes, the Interim Committee nominated Professor Schumpeter as President, M. Rueff as Vice President, and Ronald Walker (Australia) as Treasurer of the I.E.A.

Critics had turned the Pigou effect into a crude prescription for curing depressions by driving wages and prices down; Haberler writes to rescue it from that caricature. Properly understood, he argues, it is not policy advice at all but a theorem about the internal consistency of the static Keynesian model. In a world of flexible competitive wages, the Keynes effect normally restores full employment through falling interest rates; the Pigou effect closes the extreme remaining cases — a liquidity trap, interest-insensitive investment — by letting rising real balances lift expenditure. This dismantles the one strict basis for a static competitive underemployment equilibrium and undercuts secular stagnation, even as Haberler concedes to Hansen and Metzler that real depressions demand monetary and fiscal action, not patient deflation.

For these two reasons it would be foolish to rely entirely on price and wage deflation to cure a depression through the Pigou effect.

Surveying business-cycle theory at a moment when the field was fragmenting into rival methods, Haberler imposes order with a single 'modest hypothesis': fluctuations in effective demand are the immediate cause of cyclical swings in output and employment. Written in German, the essay insists this is no narrowly monetary claim — Keynesian, Wicksellian, Austrian, and Schumpeterian accounts all fit beneath it — and reformulates the demand-output link through the elasticity of aggregate supply. He treats Hicks's multiplier-accelerator model as the synthesis's high point yet rejects any mechanical accelerator, keeping only the weaker claim that rising income stimulates investment. The essay's sharpest thrust names the Achilles heel of all Keynes-inspired theory: rigid prices and wages, and an aggregation so coarse it hides the structural maladjustments between production and demand.

Es ist den modernen Konstrukteuren mathematischer Modelle vorbehalten geblieben, über alle diese Dinge hinwegzusehen und ein mechanisches Funktionieren des Prinzips anzunehmen.

English translation: “It has been left to the modern constructors of mathematical models to overlook all these matters and to assume a mechanical operation of the principle.”

The claim organizing this survey is that international trade theory is no autonomous doctrine but general price, production, monetary, and welfare theory applied to a world of nations, currencies, and immobile factors. Tracing the line from Hume's price-specie-flow mechanism and Ricardo's comparative costs through Mill and Marshall's reciprocal demand, Haberler shows how opportunity cost and general equilibrium rescued comparative advantage from the wreck of the labour theory of value. He weighs Heckscher-Ohlin factor-price equalization, the Stolper-Samuelson theorem, and Leontief's paradox, always separating sharp theorems from empirically reliable ones, and carries the same caution into terms-of-trade measurement, the foreign-trade multiplier, and purchasing-power parity. The classical free-trade case survives as a powerful benchmark — never an unconditional theorem.

There exist only rudiments of truly dynamic analysis in the field of non-monetary trade theory.