sheldon cooper

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  sheldon: why are you crying?
  penny: because i'm stupid!
  sheldon: that's no reason to cry. one cries because one is sad. for example, i cry because others are stupid and it makes me sad.
  penny: look, can we just please forget about all this extra stuff and can you just tell me what leonard does.
  sheldon: alright. leonard is attempting to learn why subatomic particles move the way they do.
  penny: really? that's it? well that doesn't sound so complicated.
  sheldon: it's not. that's why leonard does it
  
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