In "The Grand Design" Stephen Hawking claims that free will does not exist. He uses the evidence of a study in neuroscience which found that the stimulation of certain regions of the brain resulted in the stimulation of certain desires; ex. a desire to move one's right arm. But does the mere fact that we can not decide our desires mean that we don't have free will? Don't we have the ability to control these desires and act in an appropriate way? Isn't that free will?