There's surprisingly very little trouble with depth perception when everything's a wall of white, Mr. Sylar. [John's tone is dry. His eye and general face still hurt like hell, but that's going to be a while, yet.] If the food doesn't get him to stop, you might try telling him about your murders. Put it as a puzzle, and it'll probably get him talking, either to dismiss you as boring or to try to solve it before you do it for him.

Sherlock, please eat what he gives you and stop staring.