Is the Professor Actually Bugs Bunny in Disguise?

Undergrad, explaining why he can't answer a question: I'm just tired today. I'm sorry.
Very old professor, non-native English speaker: You are tired?
Student: Yes, I'm sick.
Very old professor: What disease do you have?
Student: I…uh, it's just a cold.
Very old professor: Yes, a cold is not considered disease. You are healthy. You are alive!

Classroom, University of Colorado
Boulder, Colorado