I was reading the Roger Penrose book Emperor's New Mind and he was explaining the determinism in Newtonian mechanics. He says that if we consider two solid balls colliding (assuming elastic collision) then outcome depends continuously on initial state of the balls. But if we consider triple or higher order collisions say three balls A,B,C come together at once it makes a difference if we consider A and B come together and then C to collide with B immediately afterwards or if we consider A and C to come together and then B to collide with A immediately afterwards. From this he concludes that there is indeterminism in exact triple collisions and the output depends discontinuously on the input state. I dont quite understand above conclusions. Could anyone please explain it to me??