That's a joke, Ray. It's comedy.
4 seconds sound clip from the Rain Man (1988) movie soundboard.
You can hear this line at 01:10:40 in the Blu-ray version of the movie.
Quote context
[...]
- What are you asking me for? I'm not asking you. I'm telling you.
- Who's on first. I'm asking you who's on first.
- Yo, Ray. Ray, this is not... It's not a riddle.
- Yeah. You know the fellow's name? Then who's playing first?
- You're never gonna figure out who's on first base, because Who is on first base.
- That's a joke, Ray. It's comedy.
- Sometimes his wife comes down and collects it. Whose wife?
- You got a first baseman on first? Yeah.
[...]