And mind you, saying that Essien is the more educated footballer does not mean that Xavi is not an educated footballer, I just think that Essien knows what football is a bit more because of his versatility.
I still think Essien's athletic ability is more of a reason why he can play so many positions. Xavi knows the game so well that he knows where the ball needs to go at every moment, knows where his teammates are at all times, and just has that sixth sense about him to open up play and slow it down at the whim of his hat. I'm not sure if anybody is better than him at this stuff than he is at the moment.
In my view, Essien isn't as intelligent of a player as Xavi, but can make up for it with his physical ability and drive.
It would be a hard call, but if I were to buy either Xavi or Essien, all things considered at the moment, I would take the latter as well.