"I don't know." Is that greedy? Is it merely human? Mulder squeezes her hand, letting himself be petted and doted on. She's going to stay the night - another thing that, at this point, doesn't need discussion - and he's relieved, because he's not sure he's ready to be alone. (Between her breathing and the TV, it won't be too quiet. He's not convinced he'll be able to sleep, but it won't be for lack of sound.) And he asks himself if things could be that easy. Exactly the way Scully's always wanted, getting off the road and doing something else with their lives.

Again, he says, "I don't know," but this time, he chases it with, "I've solved the mysteries that mattered most to me. I've experienced some of the most extreme possibilities out there."

But he doesn't feel done, something he'd bet isn't the answer she'd like to hear. The compulsion to keep going, to seek more even when it might only cause them both heartache, is hard to refuse. The fate of the world still hangs in the balance. Can they really raise a child knowing that an invasion might be coming? "We'd have to leave it behind, Scully. All of it. Is that even possible?"