- Traditional SayingThe saying comes from the practice of a customer looking in a horse's mouth to determine it's age.
Image Credit: "Always Look a Gift Horse in the Mouth". Editorial cartoon shows Uncle Sam examining the teeth (labeled "Wall St. Interests") of a powerful horse (labeled "Central Bank") offered by Senator Nelson W. Aldrich. By 1909, most people thought the American banking system to be badly in need of reform. Aldrich advocated the establishment of a Central Bank, a proposal opposed by progressive Democrats who saw it as an attempt by the financiers of Wall Street to gain control. Published in The New York Times, Dec. 1, 1909, p. 10