You ask me if the movements of animals are spontaneous; my answer is, "I cannot tell," but analogy points… — Jean Jacques Rousseau

You ask me if the movements of animals are spontaneous; my answer is, "I cannot tell," but analogy points that way. You ask me again, how do I know that there are spontaneous movements? I tell you, "I know it because I feel them." I want to move my arm and I move it without any other immediate cause of the movement but my own will. In vain would any one try to argue me out of this feeling, it is stronger than any proofs; you might as well try to convince me that I do not exist.

It is no more possible for me to conceive how my will moves my body than to conceive how my sensations affect my mind. I do not even know why one of these mysteries has seemed less inexplicable than the other.

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