What is a moral weakness; a failing; a weak point; a frailty. A disposition radically noble and generous, clouded and overshadowed by superficial foibles. De Quincey called?

foible — A moral weakness; a failing; a weak point; a frailty. A disposition radically noble and generous, clouded and overshadowed by superficial foibles. De Quincey. (Webster's 1913.)

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