"We are brought face to face with the intricate relationships of the innermost heart of our economic system when we remember that a political catastrophe like the Great War or a natural catastrophe like the Japanese earthquake of 1923, instead of retarding economic life, generally enlivens it, and thus tends to bring about not a crisis but a boom. Certainly catastrophes lead to an impoverishment of the economic system, but we must guard against confusing impoverishment with a crisis, all the more so as this confusion is an extremely common one. If we agree to understand by an economic crisis a temporary paralysis of the economic process which leads to a disturbance of the exchange apparatus with its consequences of over-production, surplus stocks, and insolvencies, we realize that it is characterized not by a scarcity but by a superfluity of goods, while the hall-mark of impoverishment is a deficiency of goods. This deficiency of goods generally spurs on the economic machine to make the highest number of revolutions it is capable, as was very markedly the case during the war. An economic crisis is therefore not an expression of shortage but of abundance or - to put it better - of what seems to us 'abundance' because of the temporary paralysis of the process of exchange and of the economic process in general. That it leads in the long run to an impoverishment of the economic system is self-evident, but this does not affect the question of the origin of crises, which is the question we are discussing here."