Is this line a clue?

Rating: 8/10 (27 June 2010)

In their final lines on the hospital steps Ruffalo poses DiCaprio a question that just may, just may be a clue as to whose reality in the film is authentic. Ruffalo's character is portrayed alternately as a loyal, true partner of DiCaprio's AND as deceptive conspirator with the hospital's morally corrupt staff. Appearing in his tweed suit as DiCaprio's patient, oh-so-understanding psychiatrist he lapses briefly into his deceptive role as DiCaprio's partner when he addresses DiCaprio as "boss"; if he really were DiCaprio's psychiatrist would he call his patient "boss" without correcting himself? For when he addresses DeCaprio as "boss" he's confirming DeCaprio's paranoiac delusions. If you see this film be prepared to doubt momentarily your own sanity at points. Or maybe it was just the popcorn.