In the 1870s, Leland Stanford allegedly wagered $25,000 to prove the theory that all four of a horse’s hooves leave the ground when it travels at a gallop. While the anecdote is largely considered to be untrue, the wager has been repeatedly refuted across close to a century of writing on Stanford and Eadweard Muybridge’s role in the development of motion pictures. In examining the disavowal of the wager myth, this article argues the refutations illustrate contradictions between science and representation that remain central to the history of motion-picture technology.