It’s a philosophical debate that will send your head spinning: Richard Newman stars as psychoanalyst Sigmund Freud and Damon Calderwood as British author C.S. Lewis in Freud’s Last Session, the Couch Trip Collective’s staging of the profound play by Mark St. Germain. How big are the questions the two famous brainiacs address in the work, set on the eve of both World War II and Freud’s own death? Let’s start with the existence of God and whether goodness requires the existence of evil. The show runs from next Wednesday (January 29) to February 9 at New West’s atmospheric Galbraith House, its heritage-restored salons perhaps not that unlike those where Freud conducted his talking cures.