John Maynard Keynes (1883-1946). He favored government intervention in the economy.
Most, probably, of our decisions to do something positive, the full consequences of which will be drawn out over many days to come, can only be taken as the result of animal spirits—a spontaneous urge to action rather than inaction, and not as the outcome of a weighted average of quantitative benefits multiplied by quantitative probabilities.
J. M. Keynes, The General Theory of Employment, Interest and Money, ch. 12 (1935).
