" In the afterglow of the Big Bang, humans spread in waves across the universe, sprawling and brawling and breeding and dying and evolving. There were wars, there was love, there was life and death. Minds flowed together in great rivers of consciousness, or shattered in sparkling droplets. There was immortality to be had, of a sort, a continuity of identity through replication and confluence across billions upon billions of years.
Everywhere they found life.
Nowhere did they find mind—save what they brought with them or created—no other against which human advancement could be tested.
With time, the stars died like candles. But humans fed on bloated gravitational fat, and achieved a power undreamed of in earlier ages.
They learned of other universes from which theirs had evolved. Those earlier, simpler realities too were empty of mind, a branching tree of emptiness reaching deep into the hyperpast.
It is impossible to understand what minds of that age—the peak of humankind, a species hundreds of billions of times older than humankind—were like. They did not seek to acquire, not to breed, not even to learn. They had nothing in common with us, their ancestors of the afterglow.
Nothing but the will to survive. And even that was to be denied them by time.
The universe aged: indifferent, harsh, hostile, and ultimately lethal.
There was despair and loneliness.
There was an age of war, an obliteration of trillion-year memories, a bonfire of identity. There was an age of suicide, as the finest of humanity chose self-destruction against further purposeless time and struggle.
The great rivers of mind guttered and dried.
But some persisted: just a tributary, the stubborn, still unwilling to yield to the darkness, to accept the increasing confines of a universe growing inexorably old.
And, at last, they realized that this was wrong. It wasn't supposed to have been like this.
Burning the last of the universe's resources, the final down-streamers—dogged, all but insane—reached to the deepest past. And—oh.
Watch the Moon, Malenfant. Watch the Moon. It's starting— "

― Stephen Baxter , Time (Manifold #1)