Howard: Sheldon, what the hell are you doing?
Sheldon: Same thing I've been doing for three days. Trying to figure out why electrons behave as if they have no mass when traveling through a graphene sheet.
Bernadette: With marbles?
Sheldon: I needed something bigger than peas now, didn't I?
Bernadette: Sheldon, when was the last time you got any sleep?
Sheldon: I don't know, two, three days? Not important. I don't need sleep. I need answers. I need to determine where, in this swamp of unbalanced formulas squateth the toad of truth.
Penny: [aside to Leonard] The toad of truth? Is that a physics thing?
Leonard: No, that's a crazy thing.
Bernadette: [making her way to Sheldon] Okay, Sheldon, what happens to our neuro-receptors when we don't get enough REM sleep?
Sheldon: [looks at Bernadette] They lose their sensitivity to seratonin and norepinephrine.
Bernadette: Which leads to��?
Sheldon: Impaired cognitive function.
Bernadette: Right. [firmly, pointing at his bedroom] So march in there, brush your teeth and go to bed!
Sheldon: [in a childish manner] ��But I don't wanna go to bed.
Bernadette: [firmly] I'm gonna count to three. One��
Sheldon: [exasperated] Oh, all right! [leaves]
Leonard: [shocked] That was amazing how you handled him.
Bernadette: I know how to deal with stubborn children. My mother used to run an illegal daycare center in our basement.

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