Black and white photograph of a hand with the thumb pointing up
Jean-Léon Gérôme’s 1872 painting ‘Pollice Verso’ is thought to have introduced the concept of the thumbs-up gesture as a sign of approval and the thumbs-down gesture as a sign of disapproval.
In ancient Rome, when Gladiators competed with each other in combat for entertainment, the crowd often decided if the Gladiator was to live to fight another day by giving a thumbs-down which meant swords down. If the crowd gave a thumbs-up, swords up, then it was a fight to the finish with one Gladiator dead and the winner alive.
Knight, N. (2016, October 01). Ancient Rome, thumbs up & thumbs down meant the opposite of what many think. Retrieved September 10, 2020, from https://www.thevintagenews.com/2016/08/03/ancient-rome-thumbs-up-thumbs-...