Source, in full
Anonymous saying, dating back at least to its citation in Natural Theology (1836) by Thomas Chalmers, Bk. II, Ch. III : On the Strength of the Evidences for a God in the Phenomena of Visible and External Nature, § 15, where the author states: "It has been said that there is nothing more uncommon than common sense."; it has since become misattributed to particular people, including Frank Lloyd Wright.