The fact is that optimism is pleasant so long as it is credible, but when it is not, it is intensely irritating. Especially irritating is the optimism about our own troubles which is displayed by those who do not have to share them. Optimism about other people's troubles is a very risky business unless it goes with quite concrete proposals as to how to make the troubles disappear or grow less.
Source:'On optimism' in: Mortals and Others; Bertrand Russell's American Essays, 1931-1935, v.1.
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