If thou hast Knowledge, let others light their Candle at thine.
Thomas Fuller (1654-1734) English physician, preacher, aphorist, writer
Introductio ad Prudentiam, #1784 (1727)
(Source)
Often misattributed to Margaret Fuller or Winston Churchill, frequently in modern English, e.g., "If you have knowledge, let others light their candles at it" (or "in it" or "with it").
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