Mortimer: Teddy, I'd like to introduce you to a doctor.
Teddy: Dr. Livingstone?
Dr. Gilchrist: He thinks I'm Livingstone?
Mortimer: Uh, that's what he presumes.
  
  
  
  
  
   
  
  
Teddy: Dr. Livingstone?
Dr. Gilchrist: He thinks I'm Livingstone?
Mortimer: Uh, that's what he presumes.
 Mortimer : Teddy, I'd like to introduce you to a doctor. 
 Teddy : Dr. Livingstone? 
  Dr. Gilchrist  : He thinks I'm Livingstone? 
 Mortimer : Uh, that's what he presumes. 
http://www.moviequotedb.com/movies/arsenic-and-old-lace/quote_27747.html