It’s better to keep your mouth shut and appear stupid than to open it and remove all doubt.

Mark Twain (1835-1910) American writer [pseud. of Samuel Clemens]

(Spurious)

This quotation, and close variants, are frequently attributed to Twain or Abraham Lincoln, but appears to have first been phrased this way by Maurice Switzer, Mrs. Goose, Her Book (1906): "It is better to remain silent at the risk of being thought a fool, than to talk and remove all doubt of it." Another point of origin is in the Bible, Proverbs 17:28: "Even a fool, when he holdeth his peace, is counted wise: and he that shutteth his lips is esteemed a man of understanding." See here for more information.