ideas are the eternal model (paradigm) according to which things are made; these are the images (idoli) of which the others are the imperfect copies (mimesi).  The world of sense is itself only a symbol, an allegory, a figure.  As in the sensible world there is a scale of beings from the lowest to the most perfect, that is to the material universe, so in the sphere of intellect, the type of the world, ideas are combined together by higher ideas, and these again by others still higher, and so on to the apex, the ultimate, supreme, omnipotent Idea, the Good which includes and sums up the whole.

Plato holds that matter is not the body, but that which may become the body by the plastic action of the idea, as Weber well expresses it; matter considered in itself is the indefinite (apeiron), the indefinable (aoriston), and the amorphous, and it is co-eternal with ideas, and inert; from the union of ideas and matter the cosmos had its origin, the image of the invisible deity, God in power, the living organism (Zoon), possessing a body, sense, a definite object, a soul.  The body of the universe has the form of a sphere, the most beautiful which can be conceived; the circle described in revolving is also the most perfect motion.

The stars first had their source in the Idea of Good; first the fixed stars, then the planets, then the earth, created deities; the earth produced organized beings, beginning with man, the crowning work and object of all the rest; the fruits of the earth were made to nourish him, and animals were made to become the abode of fallen souls.  Man, the microcosm, is reason within a soul, which is in its turn contained in a body.  The whole body is organized with a view to this reason.  The head, the seat of reason, is round because this is the most perfect form.  The breast is the seat of generous passions, while the bestial appetites are found in the belly and intestines.

The human soul, like the soul of the world, contains immortal and mortal elements; the intelligence or reason, and sensuality.  The immortality of the soul is also proved by the memory.  The subsequent union of life and matter in the production of the universe is the work of an intermediate, equivocal being, the demiurgos.  Thus Plato opposes the eternity of the intelligence to Ionic materialism, and the eternity of matter to the monistic theory of the Eleatics.

In the genesis of nature we again find the synthetic conception of the elements, which he estimates to be four; to which geometrical forms correspond, and the world was finally organized after its human type.  He divides the soul into several distinct and independent powers, which are ever revolving between life and death:  they inhabit the stars and depend upon them, since the soul which has been righteous on earth will be happy after death in the star to which it was originally destined; but those who on earth only