A life too full of excitement is an exhausting life, in which continually stronger stimuli are needed to give the thrill that has come to be thought an essential part of pleasure. A person accustomed to too much excitement is like a person with a morbid craving for pepper, who comes last to be unable even to taste a quantity of pepper which would cause anyone else to choke.
Source：The Conquest of Happiness, 1930, chap.4: Boredom and excitement
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