[Egon pauses, tapping his fingers against each other. He doesn't actually seem that bothered about Venkman bringing up the other dimensional Egon. However, he's still too dense to pick up that something is up with Venkman.]

They'll likely come in time, though there's no guarantee that they'll come from either of our dimensions. [He pauses again.] If another dimensional version of you, Ray, or myself arrive in this world, I would look forward to examining the differences that exist between each dimension.

[Meanwhile, Kölliker can probably hear all their thoughts, if she's not too distracted in the other room. But whether this occurs to either of them....]