The gesture of thumbs up is often believed to originate in ancient Rome following gladiatorial combat when the fate of a defeated warrior was decided by spectators watching the event. They would gesture either with thumbs downturned - to mimic the stabbing motion of a dagger - to indicate the warrior be executed, or if the warrior had fought well, an upturned thumb - or thumbs up - would signify the warrior could be spared.
拇指朝上的这个动作可能源于古罗马时代角斗士的武斗。在那时,输了的角斗士的命运将由观众决定。如果观众做出拇指朝下的手势,就像是一把匕首向下插的样子,这就意味着角斗者会被处死。如果观众认为角斗者表现得很好,则做出拇指朝上的手势,表示可以饶他一命。