Charlie Chaplin: truth and naturalism through improvisation

"While Harold Lloyd played the daredevil, hanging from clocks, and Buster Keaton maneuvered through surreal and complex situations, [Charlie] Chaplin concerned himself with improvisation. For Chaplin, the best way to locate the humor or pathos of a situation was to create an environment and walk around it until something natural happened. The concern of early theater and film was to simply keep the audience's attention through overdramatic acting that exaggerated emotions, but Chaplin saw in film an opportunity to control the environment enough to allow subtlety to come through."

(Public Broadcasting Service, 28th August 2006)