In this paper we argue that Aristotle operates with a particular theoretical model in his explanation of animal locomotion, what we call the ‘centralized incoming and outgoing motions’ model. We show how the model accommodates more complex cases of animal motion and how it allows Aristotle to preserve the intuition that animals are self-movers, without jeopardizing his arguments for the eternity of motion and the necessary existence of one eternal unmoved mover in Physics VIII. The CIOM model helps to elucidate (...) Aristotle’s two central yet problematic claims, namely that the soul is the efficient cause of animal motion and that it is the internal supporting-point necessary for animal motion. Moreover, the CIOM model helps us to explain the difference between voluntary, involuntary and non-voluntary motions, and to square Aristotle’s cardiocentrism with his hylomorphism, but also, more generally, it provides an interesting way of thinking about the place of intentionality in the causal structure of the world. (shrink)