fire, by attraction attraction, and by repulsion dire repulsion."
Plato, in a like manner, in the Timaeus, derives the Vital Principle from the elements—for like, therein, is known by like, and things are derived from first causes; and so, likewise, have things been denned by him in the treatises "upon philosophy." According to them, animal, in itself, is derived from the abstract idea of unity, and primal length, and breadth, and depth; and other things in a somewhat similar manner. It is besides maintained, but in a different sense, that the mind is unity, and knowledge duality, although, as one branch, it is unity; and that the number of the surface is opinion, that of the solid sensation, for numbers were spoken of by him as forms and first causes, and as derivatives from the elements. Thus, some things are discriminated by mind, some by knowledge, some by opinion, and others by sensation; as the numbers which represent those faculties are the forms of things.
Since the Vital Principle has to some appeared to be both motive and capable of knowing, there are writers who have combined motion and intelligence, and then represented the Vital Principle as a number endowed with self-motion.
Philosophers differ with respect to first causes, both as to their nature and number; but they who make them corporeal differ most from those who hold
