These exercises are designed for the student who desires a career playing a wide range of types or nurturing variety within her unavoidable type. But this must not discourage the actor from developing diverse physical, verbal, emotional and psychological resources and techniques. They will prevent him from repeating himself within his type and assist him as he ages and expands his type. Some of the group improvisations are purposely designed to insist that students diverge from those personal choices which have already become unconscious and overused. The ability of an actor to feel deeply and appropriately while playing a character is more often than not a God given talent.
Many brilliant actors do it naturally and have no idea how they make it happen.
Many are aided by substituting similar emotions and moments of recall from their own lives. Often, this is referred to as sense memory. Some actors are keen and constant observers of the world around them. I know an actor who found the root of Ophelia's insanity by observing shoes at the funeral of a friend. The news media has helped stock the warehouse for others.