Full transcript
0:00Thumbs up means...
0:02well, thumbs up, right?
0:05But it's not always been that way.
0:12In the Roman era, a thumbs up meant death for a gladiator.
0:17If the gladiator was to be spared,
0:19the referee would press the thumb to the top of the fist.
0:23If he flicked it up, it was bad news.
0:26There's a common misconception that a thumbs down meant death back then.
0:31It's thought to have stemmed from this painting by Jean-Léon Gérôme
0:35in 1872,
0:37which shows a colosseum crowd with arms outstretched
0:41and thumbs pointing to the ground.
0:43He got it wrong.
0:45It's though the positive meaning of thumbs up
0:48started with English archers in the Middle Ages.
0:52A fist with thumb up measured the correct brace height of the longbow,
0:56so the gesture came to mean "All is well. Ready for battle."
1:01Another origin of the gesture comes from merchants in Medieval times.
1:06They would seal a deal
1:07by licking their thumbs and pressing them together,
1:10so a thumbs up came to mean "done deal".
1:14Allied fighter pilots in World War Two
1:17used the gesture to indicate "chocks away"
1:21when they were ready for take-off,
1:23and it's thought that American GIs spread the gesture throughout Europe.
1:28Even today, Italians call it...
1:34Hitchhikers around the world hope to "thumb a lift" from passing traffic,
1:39but watch out in Greece, Sardinia and the Middle East,
1:42where a thumbs up sign is an insult
1:44and is more likely to get you into trouble than the next town.
1:48When a scuba diver gives a thumbs up,
1:51it means it's time to swim back to the surface.
1:54This signal has been known to confuse beginners.
1:58A wiggled thumbs up means the number 10 in American sign language,
2:03while a flat palm under a thumbs up is the sign for "help."
2:07In the 1990s, influential US movie reviewers Siskal and Ebert,
2:12used a thumbs up or thumbs down rating system on their TV show.
2:17They even trademarked the phrase "two thumbs up".
2:21Now, thumbs up and thumbs down signs are everywhere on the internet.
2:27Hoping for your approval.
2:29Or otherwise.