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A young fellow ought to be wiser than he should seem to be; and an old fellow ought to seem wise whether he really be so or not.

Lord Philip Dormer Stanhope Chesterfield, Philip Dormer Stanhope Earl of Chesterfield (1855). “The Works of Lord Chesterfield: Including His Letters to His Son, Etc : to which is Prefixed, an Original Life of the Author”, p.469
A young fellow ought to be wiser than he should seem to be; and an old fellow ought to seem wise whether he really be so or not.