"Your mother didn't seem real clear on what exactly you were researching."

"It's hard to explain. I'm just really starting. I mean this is lifelong."

They walked on companionably. The mountain was as unfamiliar, perhaps as much changed, as she was.

"When I first told my mom I was taking biology,” Sam said then, “she told me she had a biology question I might find out the answer to, that she'd always wanted to know. And I said I would if I could. And the question was Why is there sex?"

"Huh."

She nodded, it's true.

"And did you find out?"

"In a way. I found out what sex does—what it's good for, you could say, but don't tell any of my teachers I said it that way. But I didn't find out why sex is the way this gets done, if there could be a different way or not. I don't think anybody absolutely knows."

"And what does sex do? What's it good for? You know.” He was grinning uneasily, he could tell, but Sam's self-possession hadn't altered. Soon enough his own daughters.

"It's a way of increasing the genetic variety that evolution has to work with,” Sam said. “If an organism just divides, or reproduces asexually, new genetic material can't get in to produce variation, so all variation has to come just from replication errors, genetic material making random mistakes."

"That's what makes for variation? Errors?"

"Right. It's amazing when you think about it, I was amazed. If your DNA never made mistakes in replicating cells, you'd never die, you could live forever, but your offspring would never be any different from you, you'd never evolve. So the same process of replication that eventually kills us as individuals is the reason why we're here at all."

"And sex doubles the mistakes, the variations, that get passed on."

"Yes, sort of. Sex is the way we've come to do it. Have to have babies."

Remember Man that you are immortal, and the cause of death is love. What Hermes said, Hermes Trismegistus. Corpus Hermetica, his genetic material passing down through the ages, generating errors, making unlikely babies as others coupled with him, Bruno and all of them.

"But I don't think that's what she meant,” Sam said, looking ahead to where her mother toiled upward with tall Spofford. “I think she meant why are there, you know, boys and girls. Moms and dads, who do different things. If genetic variation has to increase, what's so good about this way? Actually the question more is, why are there men. I mean,” she said, smiling sidewise brilliantly at him, “males."

"Yes,” Pierce said. “I've wondered too."

"It's what I wrote my senior honors thesis on.” She lifted her head, listening: a bird sang, stopped. “Well, not really. I wrote a thesis on territorial singing in sparrows. You know it's only males that sing."

"But females call the tune."

"Right,” she said, and laughed. “Yes. I studied chipping sparrows. They're going nuts right now, you can hear them.... So the question is this, I didn't answer it or even try to answer it, but I thought about it—what's the advantage to putting all that energy into a song?"

"So what question did you answer? If it wasn't that."

"I studied inheritance and variation. Statistically. Not every female likes the same song. You can show that whatever attracts a female to a male's song, the same song will also attract her sisters. And a song similar to one she likes, but coming from another male, can lure her away for a quickie, you know? And if that male fathers children with her, his daughters will share their mother's predilection for that exact type of song, and his sons will inherit some of his ability to sing like that."

"And so taste shapes chance."

"And vice versa. And we get to be what we are.” She stopped, listened again. Pierce didn't know the song of the chipping sparrow, and couldn't pick it out from the chorus. “They sing so hard,” she said. “You just feel sorry for them that they have to. They can sing all night in spring. They sing in the morning even before they eat. These males. They have to."

"We don't mind,” Pierce said.

She smiled. He thought of her child self. Everything had changed but that smile, sign of an inward knowledge she couldn't have had as a five-year-old, but the same now that she had grown, and really did know better, or really had reason to think she did.

"You know,” he said, “there's a famous anthropologist who said that the biggest problem in any human society is finding something for the men to do."

"They should study emperor penguins,” she said, and he didn't know whether she meant anthropologists should, or men, or societies. “I was going to Antarctica to study them, but I got sent home. Long story. But they're amazing. The male sits on the eggs the female lays. The females go away back to the sea; the males just sit. They sit all winter long, in Antarctica, in a circle for warmth. It's dark dark dark. They don't eat. They don't move. When the chicks are born the fathers have this stored fluid they throw up to feed them with. When the females come back in the spring, stomachs full of fish, the dads are almost dead."

"Variation,” Pierce said. “A lesson to us all."

"Yes. And the females lead them to the sea."

"Amazing."

"Yes. So even if there have to be males and females, they don't always have to do the same male and female things.” She was starting to go on faster than he could go, bored maybe with his pace, but she looked back to smile at him again, her clear eyes deep and witty. “And that's not all I know."

* * * *

Pierce stopped there. White-painted boulders marked the way upward. He didn't remember anything now of that morning years ago, in the time of his madness, when he had climbed here toward the summit and not reached it: or rather what he remembered hadn't taken place here, not any longer. But something surely had taken his hand here, something, someone, an entity aware of all his failures, and spoken to him. It is not of thy charge. It had been the first day of winter. There was a dog who met him on the way. And for the first time he had seen where he stood, and that he might go on by turning around, by turning back: might find, on his own, an exit from the labyrinth of the heart, his heart, and a way out into the paradise of the world: the fragile, sorrowing, inadequate, endless paradise of the world, the only one he or anyone could ever know.

After a time a child took his hand. Roo and the girls had come up to him where he stood, and pulled him along with them. Roo sang to the girls as they all went up, an old song:

First there is a mountain

Then there is no mountain

Then there is.

Then they came out of the woods, and a high steep meadow was before them. A number of those great marbled boulders dropped by passing glaciers before the beginning of the world and called eccentrics squatted here and there amid the tender grasses, and shelves of metamorphosed rock poked out of the earth's skin like its broken bones, compound fractures. There was no path any longer, maybe because now it was evident where you must go to reach the top. A wind had come up, the mountaintop's.

"Old Mother West Wind,” said Pierce.

"And the Little Breezes,” said Vita, nodding in solemn certainty.

"What's that?” said Mary, always alert to danger, and she stopped her father and her sister.

"What?"

"That."

There was a sound that hadn't been there before, a varied, subtle sound, like wind in a cave, Pierce thought; or no it sounded not entirely natural, but not like a mechanical sound either, not a distant Cessna or far-off factory humming. And it was sweet.