"I sometimes wonder if I exist myself."
Berenger's statement in Act One expresses existential doubt and counters the well-known philosophical premise of 17th-century philosopher Rene Descartes, considered a cornerstone of Western philosophy. Descartes said, "I think, therefore I am," or, in other words, the ability to think is the only proof of existence. Berenger's thinking that he may not exist articulates the foundation of existentialist philosophy, the formula "existence precedes essence," which states that humans are born ("existence") before they gain any soul or meaning in life ("essence"). However, for Berenger, neither physical nor mental existence is enough to count for true existence; he needs a life committed to something significant. His overriding love for humanity and decision to save them constitutes his essence.