Retouch home after leaving field

[MD Longhorn]

Sane: Is the sky blue?
Insane: No, it's orange.
Sane: How can you say that, look right there, it's blue.
Insane: That car between me and the sky is orange. I see orange.
Sane: The car is not the sky. The sky is blue.
Insane: Oranges are orange. Only blueberries are blue.
Sane: We're not talking about oranges or cars, I asked about the sky.
Insane: But blueberries are not the sky. And oranges are juicy.
Sane: What in the world are you talking about?
Insane: The same thing we've been talking about all along - that blueberries are not juicy. Like I've said from the start.

At what point does the sane become insane for trying to engage with the insane?