


Thanks to Becky for this XKCD.

The rollover text (for those who insist it’s an integral part of each XKCD cartoon) was “3D graphs that don’t contact the plane in the closure area may proceed as scheduled, but be alert for possible collisions with 2D graph lines that reach the hole and unexpectedly enter the 3D space.”

Is the therapist playing off an ambiguity to humorously chide the client for being late … again?