rest. oh god please rest.

"Do you like to rehearse, or do you only like to be on stage?" This is a question I asked a Performance artist, who was teaching me in an acting course not long ago. His answer was that he liked to be on stage. What does that mean? How much of the process of acting comes from rehearsing? In order to be comfortable, some people must rehearse all before hand, and only then will they be comfortable, and the possibility of improvisation may come to bear. How much can actually be rehearsed? When memory, chance and circumstance peer at the actor on stage, anything can, and will often happen. What part does improvisation have to play in the making of the meal, that is the performance itself? Is the ability to improvisation a gift? What price can we attach to this process at all? If changes are made constantly, does that mean that a performance is happening, or is each performance a rehearsal until the final rehearsal? And if a good price is being paid for a show, what is the expectation from the audience? If audience members only watch one show, then of course they know no different anyhow, but the fact of the matter is, that the crew do, as do the actors. So if the only compunction from the Director/Actor is to be on stage, then why bother rehearsing at all?