There is no doubt that the “thumbs up” signal today means success or approval. However, thumbs either up or down was used by spectators of Roman gladiators to signify a fallen competitor should be dispatched (i.e. put to death). Hiding their thumbs by folding them into their closed fingers signaled they thought the competitor should be spared.

A version of the “thumbs up” signal is used by one of the young pigs in my new book “Angry Pigs Organized Against Gerbils: The Farmer Island War,” that I wrote with the help of our four grandchildren. In this entertaining book, one of the young pig used “hooves up” to substitute for “thumbs up” to indicate success in developing a weapon that could be used to defend the farm. Follow the continuing adventures of the pigs at our web site.