Who needs human companionship?!? Not Sheldon, this character hopes, on the episode titled "The Zazzy Substitution."
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The Big Bang Theory Season 4 Episode 3 Quotes

Leonard: Amy is judgmental, sanctimonious, and frankly just obnoxious
Sheldon: So?
Leonard: So we already have you for all that.

Sheldon: One has to navigate a labyrinth of social nonsense before one could be fed here
Amy: Really? I assumed an establishment named Cheesecake Factory would function more efficiently.
Sheldon: It's how they lure you in. I believe it's called, "bait and switch."