Spengler: "There's something very important I forgot to tell you."

Venkman: "What?"

Spengler: "Don't cross the memes."

Venkman: "Why?"

Spengler: "It would be bad."

Venkman: "I'm fuzzy on the whole good / bad thing. What do you mean, 'bad?'"

Spengler: "Try to imagine all life as you know it stopping instantaneously, and every molecule in your body exploding at the speed of light."

Stantz: "Total protonic reversal!"

Venkman: "Right, that's bad. Okay, all right, important safety tip, thanks, Egon."