The Returner said solemnly, "The return of the universe is a silent and lonely curtain call, witnessed by no one, and foreseeable by no one.
All we can be certain of is that at the end of the universal process, all civilizations have laid down their arms.
At the final moment, perhaps the choice of all civilizations is the same."
Upon hearing this, Lin Sen fell into deep thought, then slowly said, "The universe is like a dark forest, we once longed for a light to shine into this forest.
"Now, the light has indeed shone through, but it also signifies that the universe has entered its final moments.
"Does our universe endlessly circulate in such a manner, like a cosmic cycle?
"The cycle rate of human history's dynasties can be transcended, can the cosmic cycle be transcended as well?"
The Returner said, "In our realm, knowing and not knowing have no boundaries.
We have achieved the unity of subjective and objective, we have exhausted all the objective rules of this universe, yet, the ultimate fate of the universe is still beyond our knowledge.
As part of the universe, how can our cognitive boundaries surpass the framework of the universe itself?
If we look at it analogically, transcending the cycle rate of your human history's dynasties is because a 'variable' of the technological revolution was introduced, exploring more societal resources both internally and externally.
To transcend our Big Universe might also require the introduction of some 'variable'?
We have also been searching for this 'variable' of the universe."
At this moment, this conversation that spanned the stars finally touched upon its most central and critical link.
The Returner advocated for the return of the universe, but the universe has its own unique developmental laws; it doesn't necessarily need the intervention of the Returners.
In the original timeline, the Returner ultimately only broadcast a "brief" message, which was a call, but also a "epitaph" for this vast and storied universe.
It was a tribute and a remembrance to those civilizations that left a profound mark in the long river of universal history, dazzling and brilliant.
And now, the Returner might be more focused on finding that "variable."
Lin Sen's voice was steady and slow, "Do you think that I am that 'variable'?"
In the mechanical voice of the Returner, a rare tinge of indescribable complex emotion was mixed:
"The history of human civilization, including everything about the Divine Vessel Civilization, has also been carefully studied by us; everything fully conforms to our cosmic social model.
Every rise and fall of civilizations, every leap and revolution in technology, all just like trajectories already marked on the star map, clear and definite.
Yet, your emergence has become the exception to all this.
Without you, human civilization might have been an inconspicuous existence in the universe. Ever since human civilization had a Wallfacer Assistant like you, everything has been different; human civilization seems like it has grown wings, always able to create miracles in desperate situations.
It was you who gave humanity the hope to overcome the Trisolaran Civilization; it was you who drove the formation of the Shenzhou United Body; it was indeed you who led the Divine Vessel Civilization through numerous hardships, until it reached the status of a Divine-level Civilization.
You are the Wallfacer, always have been, and we can feel that now, you seem to be Wallfacing against the universe itself.
In order to study you, we made unprecedented efforts and created what might be the largest and most complex computational system in the history of this universe—a neutron star matrix computer entirely composed of 'Intelligent Neutrons'.
'Intelligent Neutrons' are formed by unfolding neutrons into two dimensions and etching precise circuits, thus endowing them with unimaginable computational power.
This process is similar to your technology for creating Sophons, but each 'Intelligent Neutron' has nearly a hundred million times the computational power of a Sophon.
Countless such 'Intelligent Neutrons' closely connected form a matrix network of neutron degenerate states; this matrix network kept expanding and finally formed that 'neutron star matrix computer'.
The number of 'Intelligent Neutrons' it contains is on the order of 10 to the 57th power, roughly equivalent to the total number of atoms in your Solar System, built using the resources of hundreds of billions of Constant Stars.
The computational power of this computer is strong enough to simulate the minute movements of every atom within the Milky Way Galaxy.
Yet, even with such immense computational power, it has always been unable to accurately depict your behavioral patterns, nor can it predict your next decisions and actions.
You are like an eternal enigma, an existence that cannot be bound by any known laws.
For the past three billion years, although we have always been quietly observing you, we never initiated contact with you; we also do not wish to interfere with you.
We can only wait silently, observe patiently, and attempt to find evidence of that 'variable' for the universe from you."
However, to this day, we still haven't obtained any crucial information from you.
We're not certain if you are the variable that will determine the fate of the universe, but undoubtedly, you are the most likely one!
Lin Sen, too, was stunned by the Returner's work; for them to have done so much for him, such computer engineering would likely take a Divine-level Civilization tens of millions of years to complete.
Lin Sen took a deep breath and slowly began, "Whether it is or it isn't, I am here in this place, genuinely existing.
"I also hope that I am that variable, perhaps, this is also the collective hope in the hearts of us all.
"Regarding this 'variable', do you have any other guesses or speculations?"
Returner: "There indeed are several guesses, but each is full of uncertainties.
We peered into the world of your thoughts before you became a Divine-level Civilization.
To avoid causing unnecessary disturbance to you, we didn't pry too deeply.
But we indeed captured some fragments from your memory; you had indeed flipped through a memoir, and we are certain it was real.
This memoir, from the perspective of Earthlings, depicted the ultimate destiny of the universe. And that outcome astonishingly agrees with what we previously extrapolated for the end of Human Civilization without your presence.
This led us to a few guesses:
The first guess, some Divine-level Civilization might have pre-played the future history for you and showed it to you.
But this guess has two major doubts: one is that we investigated all Divine-level Civilizations and found no trace; second, even if you truly saw the future history, your behavioral pattern completely contradicts our predictions.
The second guess, you might be a spokesperson for some unknown existence beyond this universe. We still have not fully understood our own universe, let alone speculate about those transcendent existences.
The third guess, and the least likely, is that you might be an individual consciousness of Human Civilization from the next universe, who for some unknown reason traveled here and merged with this universe's Lin Sen.
Your behavior pattern might be randomly and subtly fluctuating between two Lin Sens from different worlds. This also explains why you are completely unpredictable.
...
Other various conjectures and guesses indeed exist, yet, all of them involve matters beyond this universe's scope, something we deeply resist internally.
We also do not wish to learn the answer from you.
Now, as this universe is about to end, everything loses its meaning, and we just wish to chat with you during the last remnants of the universe's twilight.
Lin Sen's voice carried a hint of depth:
"In any case, an individual always seems so insignificant in front of the vast civilization, and yet, civilization itself, within the boundless expanse of the universe, is merely a drop in the ocean.
"Even if we become Wallfacers, Sword Holders of this civilization, can we truly change its fate?
"We seem to always be in a state of powerlessness to change, only able to tightly link our own fate with the fate of civilization. And the fate of civilization, in turn, inevitably blends into the unpredictable torrent of the universe's destiny.
"Yet, even so, we have never given up, perhaps at some unguarded moment, some inadvertent 'variable' might just trigger an unexpected 'transformation'."
PS: The unity of subjective and objective here is not about the legal unity of subjective and objective, which many readers may not understand.
Human cognition is a priori, usually based on universal induction.
Like the laws of physics, universally assumed valid on Earth, then they should also hold true on other planets, valid yesterday, then they should also hold in the future.
Even if not valid, it's because the physical law is not perfect.
Like we assume the conservation of energy, conservation of momentum... these are all based on our a priori cognition. Since they have always held true, we believe they will always continue to do so.
This is our subjective induction.
Any rational deduction, traced back to its source, is inevitably such subjective induction. The end of rationality is subjective.
This leads to a forever established Anthropic Law, which is also our subjective determination, but achieving this "one" cognition means accomplishing the unity of subjective and objective.
Meaning, subjectively affirming one law as valid can also be considered the "law of everything," thereby everything in the universe can be deduced.
In this perspective, the universe is knowable yet unpredictable.