If you play this video (click the sound on) and look at the man on the left side, it sounds like he’s saying “bar”. But if you look at the man on the right, it look like he’s saying “far”!
And if you close your eyes, it’s “bar” again. (via @arainert)
Update: This is called the McGurk effect.
The McGurk effect is a perceptual phenomenon that demonstrates an interaction between hearing and vision in speech perception. The illusion occurs when the auditory component of one sound is paired with the visual component of another sound, leading to the perception of a third sound. The visual information a person gets from seeing a person speak changes the way they hear the sound. People who are used to watching dubbed movies may be among people who are not susceptible to the McGurk effect because they have, to some extent, learned to ignore the information they are getting from the mouths of the “speakers”.
Update: The Vine clip I previously posted just yanked the bar/far comparison from a AsapSCIENCE video, so I’ve replaced the imposter with the real thing. (via @michaelck & jess)