"We thus comprehend, not only that the human mind is united to the body, but also the nature of the union between mind and body. However, no one will be able to grasp this adequately or distinctly, unless he first has adequate knowledge of the nature of our body. The propositions that we have advanced hitherto have been entirely general, applying not more to men than to other individual things, all of which, though in different degrees, are animated. For of everything there is necessarily an idea in God, of which God is the cause, in the same way as there is an idea of the human body; thus whatever we have asserted of the idea of the human body must necessarily be asserted of the idea of everything else. ...I will only say generally, that in proportion as any given body is more fitted than others for doing many actions or receiving many impressions at once, so also is the mind, of which it is the object, more fitted than others for forming many simultaneous perceptions; and the more the actions of one body depend on itself alone, and the fewer other bodies concur with it in action, the more fitted is the mind of which it is the object, for distinct comprehension. ...I must premise a few propositions concerning the nature of bodies. [Physics Axioms, Lemmas and Postulates follow.]"