La firma Fritz Machlup:

monetary factors cause the cycle but real phenomena constitute it

En “Hayek’s Contribution to Economics,” in Machlup, ed., Essays on Hayek. Hillsdale, MI: Hillsdale College Press, 1976, pp. 13-59.

Una explicación al resumen sucinto de Machlup lo proporciona Bob Murphy, donde compara la teoría austriaca del ciclo con la de los ciclos reales:

In a purely “real” theory of the business cycle — which was developed at places like the University of Rochester, where Plosser was dean of the business school — the economy is humming along nicely, when all of a sudden, BAM, there is a shock to technology, or resource supplies, or labor productivity. The agents in the model rationally adjust to the new situation, and with the new tradeoffs many of them now opt for more leisure. Critics dismiss this view as nuts, and mock real-business-cycle (RBC) theorists as explaining the 1930s as “the Great Vacation.”

Fortunately, the Austrian story doesn’t involve such implausible elements. Instead, the Austrians say that the economy is humming along nicely, when all of a sudden, BAM, the central bank (or more generally, the banking system in a regime of fractional-reserve banking) expands credit out of thin air and pushes down the interest rate below the level corresponding to the actual savings in the economy. Because of the monetary disturbance, and the “false” signal sent by the artificially low interest rate, entrepreneurs begin long-term projects that cannot be completed.

Once the monetary causes get the ball rolling, however, there are real distortions in how physical resources (including labor) are deployed. There are genuine mistakes — malinvestments, in Mises’s terminology — made during the boom period.

Finally, because the Austrians have a rich model of capital, they can explain why a painful bust, or recession, is necessary. In other words, after the central bank backs off and lets interest rates rise to their correct level, the entrepreneurs and workers can’t simply slap their foreheads and say, “Whoops, let’s try that again.” The economy can’t simply revert to its position on the eve of the boom, because irrevocable investment decisions have been made.