Conway distinguishes Free Will from randomness by showing that randomness is just a special case of determinism. The random numbers could have been written down before the big bang and looked up when needed, which is still predetermined.
What makes Free Will free is that it's the selection of some future state independently from the information in a particle's past light cone. Only the particle determines that part of its state. One implication is that our brains, being composed of particles, derive their free will from the sum of the particles' free will. This doesn't imply that particles are conscious or aware, it only means that certain degrees of freedom evolve according to computations performed by the particles independently.
In one of the lectures Conway goes in depth into the philosophy of free will, which he believed in at a time when it was (and still is) almost universally unfashionable.
In one of the lectures Conway goes in depth into the philosophy of free will, which he believed in at a time when it was (and still is) almost universally unfashionable.