Would you notice if I was replaced by an alien?” your girlfriend Heather asks over her Greek salad.
You’ve been dating for eight months. Surprises in the relationship are rare now, but this catches you completely off guard. “What?” you say.
“Like in Invasion of the Body Snatchers.”
“You watched Invasion of the Body Snatchers?” Heather is not a fan of the genre. It’s the only thing the two of you don’t have in common.
You mouth a piece of souvlaki. Your financial aid check finally arrived allowing you to splurge for lunch at Kostas Greek Café. You savor the taste knowing tomorrow you’ll be eating peanut butter and jelly.
“I had to watch it for sociology,” says Heather. Her hand fondles the pendant you gave her at six months. As she twists the pendant it catches the light and glows almost imperceptibly. You’re pleased that she wears it every day. “Professor Jarvis is a real sci-fi nut. For extra credit we can do a report on the one about the giant ants.”
“SF,” you begin to correct her, again, but then you realize she was teasing when she said ‘sci-fi’. She knows all your buttons. “Them,” you say around your souvlaki. “The one with the ants, it’s called Them.” You make a mental note to fit sociology into your schedule next semester.
“So, would you?” Heather asks again.
You think about it for a moment. “That depends. Are we talking about your body inhabited by an alien or an identical copy of you?”
“Is the alien acting normal or Stepford-y?”
“Definitely normal. If you didn’t know me, there’d be no way to tell there was something different about me, almost an exact copy. Could you tell it wasn’t me?”
You think if she were an exact duplicate then by definition you wouldn’t be able to tell — oh wait, this is one of those ‘relationship’ questions.
“Of course I’d know it wasn’t you,” you say with more conviction than you feel.
But Heather doesn’t let you off easy. “How?” she asks.
“Because I know everything about you.” An argument crystallizes in your mind. “I know how the rhythm of your footsteps is different in the morning than at night. Right now, I can perfectly imagine the scent of your pillow and how it differs from your favorite sweater.” Her bashful smile gives you confidence. “I can tell which prof dared to give you a ‘B’ by your tone of voice. I know by the way you move your head whether we should go someplace noisier or quieter.”
“But those are all physical things,” counters Heather. “Theoretically, they could all be duplicated.”
“Yes, but what I’m trying to say is the sum is greater than the parts. All of those things, and more, add up to an awareness of you. I would feel the difference.”
“Exactly,” she says. Her smile is now catlike, and the sharp look through her narrowed eyes tells you that your mission has just been compromised.