Irving Fisher on alternative explanations of the boom-bust cycle

15. While any deviation from equilibrium of any economic variable theoretically may, and doubtless in practice does, set up some sort of oscillations, the important question is: Which of them have been sufficiently great disturbers to afford any substantial explanation of the great booms and depressions of history?

16. I am not sufficiently familiar with the long detailed history of these disturbances, nor with the colossal literature concerning their alleged explanations, to have reached any definitive conclusions as to the relative importance of all the influences at work. I am eager to learn from others.

17. According to my present opinion, which is purely tentative, there is some grain of truth in most of the alleged explanations commonly offered, but this grain is often small. Any of them may suffice to explain small disturbances, but all of them put together have probably been inadequate to explain big disturbances.

~ Irving Fisher, "The Debt-Deflation Theory of Great Depressions," September 1933