Fiddling with the aerial doesn't always make the signal more clear. The cat is both dead and not dead (Clive understands the dead cat, but not the math). The man in the prologue is or isn't a dybbuk. The bookends suggest an unbroken cycle that may or may not relate to what characters have and haven't done. "Accept the mystery."
Rabbi Nachtner: "We can't know everything."
Larry Gopnik: "It sounds like you don't know anything! Why even tell me this story?"
Nachtner: [laughing]"First I should tell you, then I shouldn't, hoo!" [places hands on cheeks]
Gopnick to dream class: "Even though you can't figure anything out, you will be responsible for it on the mid-term."