Stanislavski's system was developed through his own cross-cultural experience as actor, director, and businessman. He constantly updated his method through inter-disciplinary studies, absorbing from a range of sources and influences, such as the modernist and avant-garde developments, yoga and Pavlovian behaviorist psychology. He introduced group rehearsals and relaxation techniques to achieve better spiritual connections between actors. Pavlovian approach worked well by conditioning actors through discipline in longer, organized rehearsals, and using a thorough analysis of characters. Stanislavski himself was involved in a long and arduous practice making every actor better prepared for stage performance and eventually producing a less rigid acting style. In his own words, Stanislavski described his early approach as "Spiritual Realism." His actors worked hard to deliver perfectly believable performances, as none of his actors wanted to hear his famous verdict, "I don't believe.