And upon the back of this circle in the Heaven of Venus, of which I now speak, is a little sphere, which revolves by itself in this Heaven, the circle of which Astrologers call Epicycle; and as the great sphere revolves about two poles, so does this little sphere:  and so has this little sphere the equatorial circle; and so much the more noble it is in proportion as it is nearer to those:  and in the arc, or rather back, of this circle is fixed the most brilliant star of Venus.  And, although it may be said that there are ten Heavens according to strict Truth, this number does not comprehend them all:  for that of which mention is made, the Epicycle, in which the star is fixed, is a Heaven by itself, or rather sphere; and it has not one essence with that which bears it, although it may be more like to it than to the others, and with it is called one Heaven, and they name the one and the other from the star.  How the other Heavens and the other stars may be is not for present discussion; let it suffice that the nature of the third Heaven, with which I am at present concerned, has been told, and concerning which all that is at present needful has been shown.

CHAPTER V.

Since it has been shown in the preceding chapter what this third Heaven is, and how it is ordered in itself, it remains to show who those are who move it.  It is then to be known, in the first place, that the movers thereof are substances apart from material, that is, Intelligences, which the common people term Angels:  and of these creatures, as of the Heavens, different persons have had different ideas, although the truth may be found.  There were certain Philosophers, of whom Aristotle appears to be one in his Metaphysics, although in the first book on Heaven and Earth incidentally he appears to think otherwise, who only believed these to be so many as there are revolutions in the Heavens, and no more; saying, that the others would have been eternally in vain, without operation, which was impossible, inasmuch as their being is their operation.  There were others, like Plato, a most excellent man, who place not only so many Intelligences as there are movements in Heaven, but even as there are species of things, that is, manners of things; as of one species are all mankind, and of another all the gold, and of another all the silver, and so with all:  and they are of opinion that as the Intelligences of the Heavens are generators of those movements each after his kind, so these were generators of the other things, each one being a type of its species:  and Plato calls them Ideas, which is as much as to say, so many universal forms and natures.