Kan kriser förutsägas?

queen-elisabeth-2Drottning Elizabeth besökte London School of Economics i november och ställde då en fråga om krisen:

How come nobody could foresee it?

Ett i mitt tyckte utmärkt svar ges av professor Mario Rizzo:

While there is a lively business in economic forecasting, it is a very crude endeavor. No economic model, past, present or future, will do well here. This is because there are many radically unpredictable (in the lay sense) elements in human decisionmaking. One important argument in this regard was made by Sir Karl Popper in The Poverty of Historicism (also endorsed by economists George Shackle and Ludwig Lachmann). Adapting the argument for our current purposes:

1. The course of economic events is strongly influenced by changes in the contents of the human mind that is, the future course of knowledge. This includes what we would call knowledge of the external world and of ourselves.
2. We cannot predict, by rational or scientific methods, the future course of knowledge (in the sense of reasonable conjectures that we will have in the future or even in the sense of our moods – animal spirits).
3. This is because if we could predict future knowledge it would not be future, but present. No one believes that we know now everything we will know in the future.
4. Therefore, we cannot predict the future course of economic events.

Dvs. nationalekonomer kommer aldrig med någon större säkerhet att kunna förutsäga när framtidens kriser kommer och vilken exakt form de kommer att ta. Att kriser kommer att komma framöver är däremot helt klart.