For two centuries, this was a thought experiment. An intellect vast enough to see everything, model everything, predict everything. So far beyond any human capacity that it served only as a philosophical limit.
It was impossible. Obviously.
The reason was hiding in plain sight. For millennia, intelligence was roughly symmetric across nodes. Nearly every consequential actor in the economy (traders, generals, bureaucrats, kings) ran on the same biological hardware, at the same clock speed, with the same limits of attention and memory. Some were smarter than others. Not by enough to break the symmetry.
This symmetry was so deep we stopped seeing it. We built everything on top of it. Markets work because no single mind can out-compute the collective. Democracy works because the planner cannot outclass the crowd. Rule of law exists because the intelligence wielding power is fallible. Every institution we have was designed for an order in which intelligence was distributed, because it had to be.
That world is ending.
We are building nodes whose intelligence exceeds human baselines not by small multiples but by orders of magnitude, across most domains that matter, simultaneously. Sensors that see. Networks that remember. Models that predict. The Demon is no longer a thought experiment. It is an engineering project, and most of the components are ahead of schedule.
The Sybilian thesis is simple: the hidden constant that held for ten millennia, symmetric intelligence across nodes, is breaking. And with it, every institution premised on that symmetry.
What follows is the account of what that symmetry held in place, and what happens as it fails.