Marsilio Ficino’s Platonic Theology, Volume II

3If every natural body devoid of soul is one thing through one form present in its whole and its parts, will not an animate body be one all the more through a soul present to the whole and to the parts? For if the soul were in only one member, it would be the form of that member alone. The other members would have other forms, and so all the members together would make, not one natural body in truth, but an aggregate like a house made of walls. Nor would each part of the animal possess the harmony and concord with every other part that it now possesses unless one soul bound the various members together—just as all the joints are not drawn together by the pull of a sinew unless the same sinew is present in them all. Add that life is present in every portion of the body, however small, and motion and sensation in most of them. These powers and operations of the soul are inward to those parts. A power and action inward to any agent cannot exist without the agent's substance. The soul is therefore in those parts, if it flourishes and acts in them.