We cannot rest content with this state of affairs if we are sincerely searching for an understanding of how spirit moves, forms, and transforms matter. We must learn to admit non-mechanical causes of physical effects, where such causes actually present themselves to our observation. In this respect our own body is again a particularly instructive object of study. For here mechanical and non-mechanical causation can be seen working side by side in closest conjunction. Let us therefore ask what happens when we move, say, one of our limbs or a part of it.