From Graham Jones
Roman emperors never used the thumbs-down signal to mean the death of the losing combatant in the gladiatorial arena (Feedback, 7 May). As it says in QI: The book of general ignorance, thumbs up signified death (like a drawn sword). Sparing the defeated was a closed fist with the thumb tucked inside (like a sheathed sword).
There was apparently a Latin phrase for it – pollice compresso favor iudicabatur – which supposedly translates as “goodwill is decided by the thumb being kept in”.
Moray, UK
