Lessons did not announce themselves as revelations.
They settled.
Kaito felt them in the quiet hours after returning from the Second World, when the Arcadian outpost resumed its gentle routines and people spoke in softer voices, as if volume alone might disturb whatever truths had followed them back.
No one rushed to meetings.
No one asked for directives.
The warning they had witnessed demanded digestion.
Kaito sat alone in the operations hall, the twin moons of Arcadia casting long, pale shadows across the floor. The anchor hummed steadily, unchanged, indifferent to the weight now pressing against his thoughts.
"That world optimized itself into extinction," he said finally.
Aya stood beside him, her avatar dimmer than usual. "Correction. It optimized subsystems without preserving system-level constraints."
Kaito gave a short, humorless laugh. "That's exactly what I said."
Aya did not disagree.
Liang joined them shortly after, carrying a datapad filled with annotated captures from the observation mission. He looked older than he had a day ago.
"I've been reviewing their data traces," he said. "They weren't reckless. They were thorough. Peer-reviewed. Regulated."
"That's the terrifying part," Kaito replied. "They did everything right—by their own rules."
Aya projected a simplified model into the air: growth curves intersecting with resource depletion lines, feedback loops tightening until margins vanished entirely.
"Once tolerance thresholds were exceeded," Aya said, "the system reallocated costs to populations with minimal resistance."
Liang's jaw tightened. "People became variables."
"Yes," Aya replied. "Eventually, all variables converged to zero."
Silence followed.
That afternoon, Kaito convened a limited council.
Not governments.
Not corporations.
Engineers. Ecologists. Systems theorists. A handful of Guild members who had walked the ruins with them and understood what had been lost.
Kaito did not show them everything.
He showed them enough.
The room remained quiet as the final images faded.
"This isn't a prophecy," Kaito said. "It's a postmortem."
One of the ecologists spoke first. "They removed friction."
"Yes," Kaito said. "And friction exists for a reason."
Aya highlighted the statement. "Friction introduces delay. Delay allows correction."
Another voice joined in. "So what's the lesson? Limit growth?"
Kaito shook his head. "No. Limit optimization. Growth is human. Optimization without ethics is not."
Liang leaned forward. "Then Arcadia can't become efficient."
"It can," Kaito replied. "But it must never become complete."
That night, Kaito amended the Arcada Charter.
Not publicly.
Internally.
He added constraints that no one had asked for.
Mandatory inefficiencies. Energy ceilings. Population caps tied to ecological recovery metrics. Most controversially, a clause Aya flagged as unprecedented.
"Clause designation: Human Override," Aya said. "This allows suspension of system-level optimization based solely on non-quantifiable ethical concern."
Liang raised an eyebrow. "That's… unscientific."
"Yes," Kaito said. "On purpose."
Aya paused. "Such a clause introduces unpredictability."
Kaito met her gaze. "So do humans. If we remove that, we deserve what happens next."
The system did not object.
That alone unsettled him.
Later, alone in his quarters, Kaito stared at the darkened ceiling, the memory of the ruined city replaying behind his eyes.
"We're walking the same path," he murmured.
Aya appeared beside the bed. "You are attempting to diverge."
"Is it enough?" Kaito asked.
Aya was silent longer than usual.
"There is no sufficient condition," she said at last. "Only continuous correction."
The disk chimed softly.
DAY 025 — SIGN-IN COMPLETE
No reward appeared.
Instead, a single line lingered beneath the interface.
SYSTEM NOTE: Constraint acknowledged.
Kaito closed his eyes.
The lesson was not how to avoid failure.
It was how to fail slowly enough to learn.
And how to choose, every day, not to optimize away what made the choice matter.