MANNHEIM, West Germany — Jokes are funnier if the audience already is smiling. This is another theory of 19th-Century naturalist Charles Darwin. It has been proven by a modern researcher.
According to Discover magazine, West German social psychologist Fritz Strack recently proved that even a "smile" forced by holding a pen in the teeth with the lips pulled back significantly, increased the humor "smilers" saw in a series of cartoons.
Darwin claimed more than a century ago that facial expressions could intensify emotions rather than just mirroring them, and that people really could be happier if they forced themselves to smile.