I know the one you're talking about, and Lois actually doesn't know. He's making her think she's seeing both of them at the same time.

I think, therefore, I get bananas.

When in doubt, think about time travel conundrums. You'll confuse yourself so you can forget what you were in doubt about.

What's the difference between ignorance, apathy, and ambivalence?
I don't know and I don't care one way or the other.