Dread of disaster makes everybody act in the very way that increases the disaster. Psychologically the situation is analogous to that of people trampled to death when there is a panic in a theatre caused by a cry of 'Fire!' In the situation that existed in the great depression, things could only be set right by causing the idle plant to work again. But everybody felt that to do so was to risk almost certain loss. Within the framework of classical economics there was no solution. Roosevelt saved the situation by bold and heretical action. He spent billions of public money and created a huge public debt, but by so doing he revived production and brought his country out of the depression. Businessmen, who in spite of such a sharp lesson continued to believe in old-fashioned economics, were infinitely shocked, and although Roosevelt saved them from ruin, they continued to curse him and to speak of him as 'the madman in the White House.' Except for Fabre's investigation of the behavior of insects, I do not know any equally striking example of inability to learn from experience.
Bertrand Russell