He is talking

Sit there. I'm just going to take a look at your chart.

Are you Dr. Fraser?

Do I look like Dr. Fraser to you?

I don't know. I've never met him.

Oh, good then. Yes, I am Dr. Fraser. Hmm, let's take a look at your chart then, BECAUSE I'M THE DOCTOR.

Are you --

Hmm. Says here you have a brain sickness.

No, I have a bad knee.

According to my diagnosis you have a brain sickness. I'm going to inject you with some brain pills.

I don't need brain pills, it's really just my knees.

Hmm. Nurse, take dictation. "Patient unaware of his brain sickness. Extra brain pills required to stop horrible delusions."

(he is talking to an empty chair)

Can you just tell me what you're going to do to my knee and then I'll go?

I'm going to have to look at your brain. Open your head, please.