Starplex

"No, you miss my meaning — doubtless due to my lack of clarity in expressing it. I'm saying forget about what has transpired between you and Jag, and between Earth and Rehbollo. I despair over how much of your mental resources — how much of your time — you humans will waste over these issues. No matter how bumpy the terrain, smooth it in your mind."

Rhombus paused for a moment, letting this sink in, then: "Well, I've used the seven minutes you granted me; I should leave now." The Ib began to roll away.

"People have died," said Keith, raising his voice. "It's not that easy to smooth it all out."

Rhombus stopped. "If it is difficult, it is only because you choose for it to be that way," he said. "Can you foresee any solution that will bring the dead back to life? Any reprisals that won't result in more people dead?" Lights played across his web. "Let it go."

ETA DRACONIS

Glass looked at Keith, and Keith looked at Glass. Something 'in the being's manner told Keith this would be their final conversation.

"You mentioned during your introductory speech that your Commonwealth currently consists of three home-worlds," said Glass.

Keith nodded. "That's right," he said. "Earth, Rehbollo, and Flatland."

Glass tipped his head. "There are, in fact, only seven thousand worlds with native life on them in this entire universe at your time — and those few worlds are spread out over all the billions of galaxies. The Milky Way has far more than its fair share: during your time, there are a total of thirteen intelligent races within it."

"I'll keep score," said Keith, smiling. "I won't give up until we've found them all."

Glass shook his head. "You will find them eventually, of course — when they're ready to be found. The shortcuts' facilitating of interstellar travel isn't just a side effect of their shunting stars back to the past. Rather, it's an integral part of the plan. But so is the safety valve that keeps sectors of space isolated until their native inhabitants become starfarers on their own. Of course, if you have the appropriate key, as I do, you can travel between any shortcuts, even apparently dormant ones. That's important, too, because we shortcut makers will need to make extensive use of them. But the way they work without the key is designed to foster an interstellar community, to give rise to the kind of peaceful and cooperative future that's in everyone's interest."

Glass paused, and when he resumed speaking, his tone was a little sad.

"Still, you won't be able to keep score of how many races you have yet to discover. When I send you back, I will wipe your memories of the time you've spent here."

Keith 's heart fluttered. "Don't do that."

"I'm afraid I must. We have an isolation policy."

"Do you — do you do this often? Grab people from the past?"

"Not as a rule, no, but, well, you're a special case. I'm a special case."

"In what way?"

"I was one of the first people to become immortal."

"Immortal…" Keith's voice trailed off.

"Didn't I mention that? Oh, yes. You're not just going to live for a very long time — you're going to live forever."

"Immortal," said Keith again. He tried to think of a better word, but couldn't, and so simply said, "Wow."

"But, as I said, you — l — we are a special case of immortality."

"How so ?"

"There are, in fact, only three older human beings than me in the entire universe. Apparently, I had a — what do you call it? — an 'in' that got me the immortality treatments early on."

"Rissa was working on senescence research; I assume she ended up being codeveloper of the immortality technique."

"Ah, that must have been it," said Glass.

"You don't remember?"

"No — and that's the whole problem. You see, when they first invented immortality, it worked by allowing cells to divide an infinite number of times, instead of succumbing to preprogrammed cell death."

"The Hayflick limit," said Keith, having learned all about it in conversations with Rissa.

"Pardon ?" "The Hayflick limit. The phenomenon that limits the number of times a cell can divide."

"Ah, yes," said Glass. "Well, they overcame that. And they overcame the old, natural limitation that said you were born with a finite quantity of brain cells, and that those cells were not normally replaced. One of the keys to immortality was to let the brain constantly create new cells as the old ones wore out, so-"

"So if the cells are replaced," said Keith, eyes growing wide, "then the memories stored by the original cells get lost."

Glass nodded his smooth head. "Precisely. Of course, now we offload old memories into lepton matrices. We can remember an infinite amount of material I don't just have access to millions of books, I actually remember the contents of millions of books that I've read over the years.

But I became an immortal before such offloading existed.

My early memories — everything from my first couple of centuries of life — is gone."