He was too diffident to do justice to himself; but when his natural shyness was overcome, his behaviour gave every indication of an open, affectionate heart.
—He thinks Marianne’s affection too deeply rooted for any change in it under a great length of time, and even supposing her heart again free, is too diffident of himself to believe, that with such a difference of age and disposition he could ever attach her.
She liked him, however, upon the whole, much better than she had expected, and in her heart was not sorry that she could like him no more;— not sorry to be driven by the observation of his Epicurism, his selfishness, and his conceit, to rest with complacency on the remembrance of Edward’s generous temper, simple taste, and diffident feelings.
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She is diffident around adults, but dominant with her peer group.
At first, he could give no encouragement; with unfeigned diffidence, he expressed his conviction that he was not adequate to the performance of so great a task;
Frederick Douglass -- The Narrative of the Life of Frederick Douglass