Star Trek: Deep Space Nine: Fearful Symmetry

Prologue
Seven days ago
The world receded behind an infinite vista of radiant white, until all that remained was the beating of his heart -- the steady rhythm that kept him anchored to his life on the linear plane. He found his hand, long brown fingers flexing above his open palm, just as he had done during his original encounter with the Prophets. And like that first time, he came to understand that he was not alone.
But he had intuited from the start that this was not to be another meeting with the wormhole entities. His sudden need to experience the Orb that had guided him here had come from his vague sense of a different sort of connection, one deep in the center of his being...something that transcended even the most intimate relationships of his linear life. As his awareness continued to spread outward, he started to recognize those who were already assembled here: seven others who had, like him, been drawn by necessity to this place that was not a place, at a time when there was no time. He walked forward into a circle of Emissaries.
A gathering of men named Benjamin Sisko.
They looked at one another across the whiteness, men from different universes; each one, like him, born by design, and each of whom in time -- despite how differently their lives had unfolded -- had met his destiny on a world called Bajor.
Ben felt the void at once, a cold and yawning emptiness very close by, like a missing piece of his soul. To his immediate right, there was a break in the circle. Someone was missing.
"I take it," he said, "that we're here to do something about the hole in our ranks."
"Not us," said one of the others. "You."
Ben's gaze fixed upon the speaker, a clean-shaven civilian wearing the formal attire of a Federation diplomat, and as their identical eyes met, his counterpart's life and the world from which he came were suddenly an open book: Ambassador Sisko of the UFP Diplomatic Corps, who had lost his wife Jennifer on Cardassia Prime during a suicide attack by Kohn-Ma terrorists, even as he was trying to negotiate the withdrawal of Cardassia's military forces from Bajor....
Ben heard his heart beating faster. He focused on the sound, followed it back to his true self, realizing that it would be all too easy to become lost in the alternate lives arrayed around him. "I don't understand."
"He was your responsibility," someone else said. Ben turned and focused past the break in the circle, where another counterpart was gesturing toward the vacant space between them. What appeared to be a dagger was sheathed in the sashlike belt of his gaudy metallic uniform: Fleet Captain Sisko, the military governor of Bajor under a Terran Empire that never fell, the livid scar across his right, sightless eye the only legacy of the father who had betrayed him. "It was your task to reach him, to convince him to take his place among us."
"What are you talking about?" Ben asked. "I never even met our counterpart in that reality. How is anything about him or that universe my responsibility?"
"You ignored the signs," the imperial said.
"What signs? Every crossover was their doing, except for the first one, and that was entirely by accident!" As he spoke, the events of that original contact came back to him: Nerys and Julian's runabout mysteriously malfunctioning as it entered the wormhole, out of control until it emerged, inexplicably, in the alternate universe of the Intendant.
Then he paused, comprehension slowly dawning...along with the terrible realization that he had been blind to a pattern that had been there before him all along.
"It wasn't an accident at all," Ben said. "The Prophets wanted our two universes to connect."
"You're starting to understand," said another civilian, this one full-bearded and wearing a blue laboratory jumpsuit: Dr. Sisko of the Daystrom Institute, whose discovery of the wormhole years after the terrible accident that had claimed the life of his sister had led, not to strife, but to a new renaissance of art, science, and philosophy -- and to a spreading social revolution in which the free exchange of knowledge and ideas was catalyzing a gradual dismantling of the familiar galactic nation-states in favor of a loose but stable interstellar sprawl. "Every other crossover was initiated by their side, just as you said," the scientist continued. "And more tellingly, they all occurred by transporter. But your Kira and Bashir's runabout went through the wormhole to get there and back that first time, and you never stopped to consider the possibility that it wasn't a random event, or that your two universes seemed unusually permeable in the Bajoran system after that first event. You never wondered why no one in that universe ever opened their Temple Gates, despite the presence of a Sisko in that continuum. Not even after you learned the truth about your origins...that Benjamin Sisko does not exist by accident, in any universe."