Best Argument Against Same-Sex Marriage

Isaac Davis: I got a kid, he's being raised by two women at the moment.

Mary Wilke: Oh, y'know, I mean I think that works. Uh, they made some studies, I read in one of the psychoanalytic quarterlies. You don't need a male, I mean. Two mothers are absolutely fine.

Isaac Davis: Really? Because I always feel very few people survive one mother.

-- from Woody Allen's Manhattan (1979)