Among politicians good men have their uses, the chief of which is to afford a smoke-screen behind which others can carry on their activities unsuspected. A good man will never suspect his friends of shady actions : this is part of his goodness. A good man will never be suspected by the public of using his goodness to screen villains : this is part of his utility.
Source: Bertrand Russell: The Harm That Good Men Do，1926.
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