Continuity mistake: Near the middle when Sy is imagining he is in the Yorkin's home, he is sitting on the couch watching a ballgame. Behind the couch is a tall white square sculpture. Sy turns to the dog and says, "Good game." When the camera goes back to Sy, look behind the couch, the sculpture has disappeared. But when you see the Yorkins come in the door, and the camera goes back to Sy on the couch, the sculpture has reappeared.
Picture added by Lummie