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Ray, you're never gonna solve it. It's not a riddle because Who is on first base. That's a joke, Ray, it's comedy, but when you do it you're not funny. You're like the comedy of Abbott and Abbott.
— Charlie ‧ Rain Man

Behind the line May contain spoilers.
Our reading
An editorial interpretation.
The speaker explains that the baseball routine depends on wordplay, not on solving a riddle. Calling Ray the comedy of Abbott and Abbott suggests he has lost the contrast between the partners that makes the exchange funny. Taking the names literally defeats the joke.
Context reviewed