You've probably been wondering, "Is there any data about facial hair, particularly gloriously groomed beards?" Why, yes, there is. Find out how facial hair transforms perception and whether or not it could help blunt a few blows in a bar fight, all in this classic episode of Stuff to Blow Your Mind.
Image: Detail of a painting from 'Nibelung Saga' by Julius Schnorr von Carolsfeld. (© Adam Woolfitt/Corbis)