[PTTG]

In De Chancie, the current year is a vaguely recognizable 2000 where computers are exploding in importance. In this history, Alan Turing uncovered a fundamental logical principle tying models to the things they simulate. Serious mathematicians called it Commutative Simulation. Everyone else calls it actual magic.

Commutative Simulation is a set of principles that allow a computer program's simulation of the world to actually alter the real world. This is limited by the resolution of the simulation, the size thereof, and the energy powering the computer. In principle, it's even possible to do the work with just hand-written math, though anything practical to do by hand is nearly undetectable.

This was studied intensely for decades, and finally reached fruition in 1990. What had previously been the purview of private research institutions and government black labs reached consumer's hands in the form of the (inevitably-named) MERLIN-PC (Micro Electronic Linear Information Networking Personal Computer). Developed in this world's computing nexus (the Silicon Moor) of Chester, UK, the computer allowed a skilled programmer to make a flower bloom, a match ignite, or a slight breeze to blow about the room, or similar trivial effects.

Ten years on, and the consequences of this sort of magical workings undergoing exponential growth are still being discovered...