There is my arm seen as sustaining familiar acts, my body as giving rise to determinate action having a field or scope known to me in advance, there are my surroundings as a collection of possible points upon which this bodily action may operate, and there is, furthermore, my arm as a mechanism of muscles and bones, as a contrivance for bending and stretching, as an articulated object, the world as a pure spectacle into which I am not absorbed, but which I contemplate and point out.