"We live in an era somewhere near the start of the contact between species, on an interstellar scale," Shira said. "There is war, death, destruction. Genocide. But one can, from a godlike perspective, regard it all as interfacing — as a sharing, a pooling, of information.

"Ultimately, surely, the squabbling species of our day will resolve their childish differences — differences of special prejudice, of narrow interests, of inadequate perception and move together, perhaps under the leadership of the Xeelee, toward the ultimate goal of life: the gathering and recording of all data, the observation and invocation of the universe itself."

More and more resources would be devoted to this goal — not just in extent, as life spread from its myriad points of origin, but in depth and scope. At last all the energy sources available for exploitation, from the gravitational potential of galactic superclusters down to the zero-point energy inherent in space itself, would be suborned to the great project of consciousness.

Shira described the future of the universe.

In a few billion years — a blink of cosmic time — Earth’s Sun would leave the main sequence of stars, its outer layers ballooning, swallowing the remains of the planets. Humanity would move on, of course, abandoning the old in favor of the new. More stars would form, to replace those that had failed and died… but the formation rate of new stars was already declining exponentially, with a half-life of a few billion years.

After about a thousand billion years, no more stars would form. The darkened galaxies would continue to turn, but chance collisions and close encounters would take their cumulative toll. Planets would "evaporate" from their parent suns, and stars would evaporate from their galaxies. Those stars remaining in the time-ravaged star systems would lose energy, steadily, by gravitational radiation, and coalesce at last into immense, galactic-scale black holes.

And those holes themselves would coalesce, into holes on the scales of galactic clusters and superclusters; from all across the universe the timelines would converge, merging at last into the great singularities.

But life would prevail, said Shira, continuing to exploit with ever-increasing efficiency the universe’s residual sources of energy. Such as the dim shining of the star-corpses, kept at a few degrees above absolute zero by the slow decay of protons.

And there would still be work to be done.

Black hole evaporation would continue, with the eventual shrinking and disappearance of event horizons even on the scale of galaxies and clusters of galaxies; and naked singularities would emerge into the spreading sweep of spacetime.

Perhaps the universe could not exist beyond the formation of a naked singularity. Perhaps the formation of such a flaw would cause the cessation of time and space, the ending of being.

"And perhaps," Shira said, "life’s purpose, in the later stages of the evolution of the universe, is to manipulate event horizons in order to prevent the formation of naked singularities."

"Ah." Parz smiled. "Another elegant idea. So our descendants might be entrained to work as Cosmic Censors."

"Or as Cosmic Saviors," Michael said dryly.

Harry asked, sounding awed, "How do you manipulate event horizons?"

"No doubt there are lots of ways," Michael said. "But even now we can imagine some fairly crude methods. Such as forcing black holes to merge before they get a chance to evaporate."

"The Wigner paradox is inescapable," Shira said. The chains of unresolved quantum states would build on and on, growing like flowers, extending into the future, until the observations of the cosmos-spanning minds to come rested on aeon-thick layers of history, studded with the fossils of ancient events. "At last," Shira said, her voice steady and oddly flat, "life will cover the universe, still observing, still building the regressing chains of quantum functions. Life will manipulate the dynamical evolution of the cosmos as a whole. One can anticipate the pooled resources of life exploiting even the last energy resource, the sheer energy of the expansion of spacetime itself…

"Consciousness must exist as long as the cosmos itself — for without observation there can be no actualization, no existence — and further, consciousness must become coextensive with the cosmos, in order that all events may be observed."

Parz laughed softly, wondering. "What a vision. Girl, how old are you? You sound a thousand years old."

But, Shira went on, the chains of quantum functions would finally merge, culminate in a final state: at the last boundary to the universe, at timelike infinity.

"And at timelike infinity resides the Ultimate Observer," Shira said quietly. "And the last Observation will be made—"

"Yes," Parz said, "and so collapsing all the chains of quantum functions, right back through time — through the wreckage of the galaxies, down to the present and on into history, past Wigner, his friend, the cat and its box — what a charming notion this is—"

"Retrospectively, the history of the universe will be actualized," Shira said. "But it cannot be realized until the final Observation." For the first time since resuming her seat she turned to Michael. "Do you understand the implications of this, Michael Poole?"

He frowned. "These ideas are staggering, of course. But you’ve gone one step further. Haven’t you, Shira? There’s still another hypothesis you’ve made."

"I… Yes." She bowed her head in an odd, almost prayerful attitude of respect. "It is impossible for us to believe that the Ultimate Observer will simply be a passive eye. A camera, for all of history."

"No," Michael said. "I think you believe that the Ultimate Observer will be able to influence the actualization. Don’t you? You believe that the Observer will have the power to study all the nearly infinite potential histories of the universe, stored in the regressing chains of quantum functions. And that the Observer will select, actualize a history that is — what?"

"Which is simply the most aesthetically pleasing, perhaps," Parz said in his dry, aged way.

"Which maximizes the potential of being," Shira said. "Or so we believe. Which makes the cosmos through all of time into a shining place, a garden free of waste, pain, and death." She lifted her head abruptly; the light from the data panel before her struck shadows in her face, and Michael was moved by the contrast between the skeletal gauntness of the girl’s intense face and the beauty — the power, the wistfulness — of her concepts.

Harry said, his voice heavy with wonder. "A god at the end of time. Is it possible?"

Michael found he wanted to reach the girl, and he tried to put tenderness into his voice. "I understand you now, I think," he said. "You believe that none of this — our situation here, the Qax Occupation of Earth, the Qax time invasion — is real. It’s all transitory, in a sense; we are simply forced to endure the motion of our consciousness along one of the chains of quantum functions that you believe will be collapsed, discarded, by your Ultimate Observer, in favor of—"

"Heaven," Harry said.

"No, nothing so crude," Michael said. He tried to imagine it, to look beyond the words. "Harry, if she’s right, the ultimate state — the final mode of being of the cosmos — will consist of global and local optimization. Of the maximizing of potential, everywhere and at every moment, from the beginning of time." Shining, Shira had said. Yes, shining would surely be a good word for such an existence… Michael closed his eyes and tried to evoke such a mode; he imagined this shoddy reality burning away to reveal the pure, clear light of the underlying optimal state.

Tears prickled gently at his closed eyes. If one were vouchsafed a glimpse of such a state, he thought, then surely one would, on being dragged back to the mire of this unrealized chain of being, go insane.