From The Drama of Doctrine:
The Method is all about avoiding mechanical acting. In Stanislavski’s words: “Never allow yourself externally to portray anything that you have not inwardly experienced and which is not even interesting to you” –an apt piece of advice for aspiring disciples too. The mechanical actor reproduces outward expressions without actually feeling what they seek to express. Mechanical acting suffers from a lack of coincidence between the inner and outer man and is therefore the theatrical equivalent of hypocrisy. Stanislavski also warns his students against the use of a mirror: “It teaches an actor to watch the outside rather than the inside of his soul, both in himself and in his part.” He is equally severe with those who “overact” and bemoans the fact that “our art is frequently exploited for personal ends” such as fame and money–yet another parallel, sad to say, between the theater and the church. Actors who exploit the theater are the “deadliest enemies of art,” just as those who exploit the church are deadliest enemies of faith.” ~Kevin Vanhoozer