Kairos Function Mark
"Some speculate that the radiolarian fluid is the last vestige of a biological life-form that became the Vex." —Sister Faora, "Theories on the Vex"
Compartmentalization. Isolate the pieces of a network, so that 1) each subnet may operate independently, and 2) any harm that befalls one subnet will not necessarily befall the rest. The Vex learned this lesson well. Many subnets, many equations, all executing toward the same answer: convergence. They gambled that eventually, one of their subnets will achieve it. Speaking in purely mathematical terms, it's a very safe bet.
In that conceptual framework, you see how the Forest, "infinite" in so many ways, is still only a small fraction of the Vex's true capabilities. Imagine the decimal two-point-one repeating. Its precise value is incalculably infinite, and yet you know that beyond its irrational depths waits two-point-two. Two-point-three. Two-point-four…