I did improvisational theatre while I was in high school. It was pretty much the only type of theatre I was decent at; I was horrible at memorizing lines, and my expressions were too over-the-top. Improv came naturally to me though, and I ran with it. In participating in it, I learned a valuable life lesson.
To be good at improv, there is one rule you have to engrain into your skull. It's known as the "Yes, And" Rule. The "Yes, And" Rule is simple... whenever an idea is brought into a scene, the actors must accept it as true (the yes) and commit to incorporating it throughout the scene. This builds continuity, momentum, and integrity.
The reason this is the key rule to success in improv is that if an actor were to say no to an idea, it would destroy the validity of the scene. Improv lives and dies on the fact that it is performed on an empty stage. The possibilities of scenes are endless, and it is the actors' responsibility to turn this emptiness into a setting full of life, drama, and action. The audience is looking to believe everything an actor presents them. But when an actor says no to something, it confuses the beliefs of the audience while ruining the integrity of the scene, and the audience and the actors are brought back to how the scene began... emptiness.
The hardest part of the "Yes, And" Rule is committing to the yes. In an environment full of possibilities, saying yes determines a direction that you must go towards and live with. Saying no is easy because it keeps those possibilities available. But saying yes, and committing, builds a scene full of action and entertainment. Saying no is having potential; saying yes is fulfilling that potential.
