Peters: How did you know she was lying?
Shawn: I'm a psychic, Peters.
Gus: How did you know she was lying?
Boones and Peters: [in unison] She's a woman.
Shawn: I'm a psychic, Peters.
Gus: How did you know she was lying?
Boones and Peters: [in unison] She's a woman.
Peters : How did you know she was lying?
Shawn : I'm a psychic, Peters.
Gus : How did you know she was lying?
Boones and Peters : [in unison] She's a woman.
http://www.tv-quotes.com/shows/psych/quote_33211.html