Background: Lee Strasberg (born Israel Strasberg; November 17, 1901 - February 17, 1982) was a Polish-born American actor, director, and theatre practitioner. He co founded, with directors Harold Clurman and Cheryl Crawford, the Group Theatre in 1931, which was hailed as "America's first true theatrical collective". In 1951, he became director of the nonprofit Actors Studio in New York City, considered "the nation's most prestigious acting school", and in 1966, was involved in the creation of Actors Studio West in Los Angeles.
Context: Kazan biographer Richard Schickel described Strasberg's first experiences with the "art" of acting: He dropped out of high school, worked in a shop that made hairpieces, drifted into the theater via a settlement house company and ... had his life-shaping revelation when Stanislavski brought his Moscow Art Theatre to the United States in 1923. He had seen good acting before, of course, but never an ensemble like this with actors completely surrendering their egos to the work.... [H]e observed, first of all, that all the actors, whether they were playing leads or small parts, worked with the same commitment and intensity. No actors idled about posing and preening (or thinking about where they might dine after the performance). More important, every actor seemed to project some sort of unspoken, yet palpable, inner life for his or her character. This was acting of a sort that one rarely saw on the American stage ... [w]here there was little stress on the psychology of the characters or their interactions.... Strasberg was galvanized. He knew that his own future as an actor - he was a slight and unhandsome man - was limited. But he soon perceived that as a theoretician and teacher of this new 'system' it might become a major force in American theater. Strasberg eventually left the Clare Tree Major School to study with students of Stanislavski - Maria Ouspenskaya and Richard Boleslavsky - at the American Laboratory Theatre. In 1925, Strasberg had his first professional appearance in Processional, a play produced by the Theater Guild. According to Schickel: What Strasberg... took away from the Actor's Lab was a belief that just as an actor could be prepared physically for his work with dance, movement, and fencing classes, he could be mentally prepared by resort to analogous mental exercises. They worked on relaxation as well as concentration. They worked with nonexistent objects that helped prepare them for the exploration of equally ephemeral emotions. They learned to use "affective memory", as Strasberg called the most controversial aspect of his teaching - summoning emotions from their own lives to illuminate their stage roles.... Strasberg believed he could codify this system, a necessary precursor to teaching it to anyone who wanted to learn it... [H]e became a director more preoccupied with getting his actors to work in the "correct" way than he was in shaping the overall presentation. CANNOTANSWER
Question: What was the revelation that shaped his life?. Whats the answer?

H]e observed, first of all, that all the actors, whether they were playing leads or small parts, worked with the same commitment and intensity.