Diko was the one who brought him through these first days, being careful not to take over, but instead making sure that all decisions were jointly reached; that anytime he needed her advice even to know what the choices were, she prompted him only privately, where no one could see, so that the others wouldn't come to think of her as the "real" head of the intervention team. And soon enough Hunahpu began to feel more confident, and then the two of them really did lead together, often arguing over various points but never making a decision until both agreed. No one but Hunahpu and Diko themselves could have been surprised when, after several months together, each came to realize that their professional interdependence had turned to something much more intense and much more personal.

It was maddening to Hunahpu, that he worked with Diko every day, that every day he grew more sure that she loved him as much as he loved her, and yet she refused any hint, any proposal, any outright plea that they extend their friendship beyond the corridors of Pastwatch and into one of the grass huts of Juba.

"Why not?" he said. "Why not?"

"I'm tired," she said. "We have too much to do."

Normally he let this sort of answer stop him, but not today, not this time. "Everything is running smoothly in our project," he said. "We work together perfectly, and the team we've assembled is reliable and efficient. We go home every night at a reasonable hour. There is time, if only you took it, for us to -- to eat a meal together. To sit and talk as a man and a woman."

"There is no time for that," she said.

"Why?" he demanded. "We're close to ready, our project is. Kemal is still puttering along with his report on probable futures, and the machine is nowhere near done. We have plenty of time."

The distress on her face usually would be enough to silence him, but not now. "This doesn't have to make you unhappy," he said. "Your mother and father work together just as we do, and yet they married and had a child."

"Yes," she said. "But we will not."

"Why not! What is it, that I'm so much smaller than you? I can't help the fact that Maya people are shorter than a Turko-Dongotona."

"You are so stupid, Hunahpu," she said. "Father is shorter than Mother, too. What kind of idiot do you think I am?"

"Such an idiot that you're in love with me just as I'm in love with you, only for some insane reason you refuse to admit it, you refuse even to take a chance on us being happy together."

To his surprise, tears came to her eyes. "I don't want to talk about this," she said.

"But I do," he said.

"You think you love me," she said.

"I know I love you."

"And you think I love you," she said.

"I hope for that."

"And maybe you're right," she said. "But there's something that both of us love more.

"What?"

"This," she said, indicating the room around them, filled with TruSite IIs and Tempoviews and computers and desks and chairs.

"People in Pastwatch love and live as human beings," he answered.

"Not Pastwatch, Hunahpu, our project. The Columbus project. We're going to succeed. We're going to assemble our team of three who will go back in time. And when they succeed, all of this will cease to be. Why should we marry and bring a child into the world in order to cause it to disappear in only a few more years?"

"We don't know that," said Hunahpu. "The mathematicians are still divided. Maybe all we create by intervening in the past is a fork in time, so that both futures continue to exist."

"You know that that is the least likely alternative. You know that the machine is being built according to the theory of metatime. Anything sent back in time is lifted out of the causal flow. It can no longer be affected by anything that happens to the timestream that originally brought it into existence, and when it enters the timestream at a different point, it becomes an uncaused causer. When we change the past, this present will disappear."

"Both theories can explain the way the machine works," said Hunahpu, "so don't try to use your superior education in mathematics and time theory against me."

"It doesn't matter anyway," said Diko. "Because even if our time continues to exist, I won't be in it."

There it was -- the unspoken assumption that she would be one of the three who went back in time.

"That's ludicrous," he said. "A tall black woman, going to live among the Taino?"

"A tall black woman with a detailed knowledge of events that still lie in the future for the people of the surrounding tribes," she said. "I think I'll do well enough."

"Your parents will never let you go."

"My parents will do whatever it takes for this mission to succeed," she answered. "I'm already far more qualified than anyone else. I'm in perfect health. I've been studying the languages I'll need for that aspect of the project -- Spanish, Genovese, Latin, two Arawak dialects, one Carib dialect, and the Ciboney language that is still used in Putukam's village because they think it's so holy. Who else can match that? And I know the plan, inside and out, and all the thinking that went into it. Who can do better than I to adapt the plan if things don't go as expected? So I will go, Hunahpu. Mother and Father will fight it for a while, and then they'll realize that I am the best hope of success, and they'll send me."

He said nothing. He knew that it was true.

She laughed at him. "You hypocrite," she said. "You've been doing just what I've been doing -- you've designed the Mesoamerican part of the plan so that only you can possibly do it."

That too was true. "I'm as natural a choice as you are -- more natural, because I'm a Maya."

"A Maya who's more than a foot taller than the Mayas and Zapotecs of the period," she retorted.

"I speak two Mayan dialects, plus Nahuatl, Zapotec, Spanish, Portuguese, and both of the Tarascan dialects that matter. And all your arguments apply to me as well. Plus I know all the technologies we're going to try to introduce and the detailed personal histories of all the people we have to deal with. There is no choice but me."

"I know it," said Diko. "I knew it before you did. You don't have to persuade me."

"Oh," he said.

"You are a hypocrite," she said, and there was some emotion behind it. "You were all set to go yourself, and yet you expected me to stay behind. You had some foolish notion that we would marry and have a baby, and then I would stay behind on the off chance that there would be a future here while you went back and fulfilled your destiny."

"No," he said. "I never really thought of marriage."

"Then what, Hunahpu? Sneaking off to some sordid little rendezvous? I'm not your Beatrice, Hunahpu. I have work of my own to do. And unlike the Europeans and, apparently, the Indies, I know that to mate with someone without marriage is a repudiation of the community, a refusal to take one's proper role within the society. I won't mate like an animal, Hunahpu. When I marry it will be as a human being. And it will not be in this timestream. If I marry at all, it will be in the past, because that's the only place where I have a future."

He listened, leaden at heart. "The chance of our both living long enough to meet there is small, Diko."

"And that, my friend, is why I refuse all your invitations to extend our friendship beyond these walls. There's no future for us."

"Is the future, is the past, all that matters to you? Don't you have just a little bit of room for the present?"

Again the tears flowed down her cheeks. "No," she said.

He reached up and cleared her cheeks with his thumbs, then streaked his own cheeks with her tears. "I will love no one but you," he said.

"So you say now," she said. "But I release you from that promise and I forgive you already for the fact that you will love someone, and you will marry, and if we ever meet there, we will be friends and be glad to see each other and we will not regret for one moment that we did not act foolishly now."