Man is an animal, and his happiness depends upon his physiology more than he likes to think. This is a humble conclusion, but I cannot make myself disbelieve it. Unhappy businessmen, I am convinced, would increase their happiness more by walking six miles every day than by any conceivable change of philosophy. This, incidentally, was the opinion of Jefferson, who on this ground deplored the horse. Language would have failed him if he could have foreseen the motor car.
Source: Bertrand Russell : The road to happiness (1952)
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