I've long had a theory that the stones only accelerate a process that can happen on it's own. Before, I only knew that the Eeveelutions would seem to suggest this is true. What's supposed to happen is that Eevee adapts to it's environment, taking on the elemental properties it possesses. (or in the case of Sylveon, it evolves through love and care) I've recently been pointed out a peculiar piece about Vulpix's entries. It seems it continues to gain more tails the older it gets. This would seem to suggest it can become Ninetales without a stone. I don't know if any of the other stone evos have something like this, but it would seem to suggest my theory is correct, and the stones are not necessary for evolving. What do you think? Do you have your own theories on the stones or how these evos work? Or even why it is these pokemon respond to stones and nothing else in their type does not. This is the only part I cannot resolve unless the stones aren't really necessary.