7. Now in regard there are four first bodies in the universe, which, by reason of their number, their being uncompounded, and their efficacy, are allowed for the most part to be the principles and beginnings of all other,—that is to say, fire and water, air and earth,—is there not the same necessity that there should be as many first and uncompounded qualities? And what are they but heat and cold, drought and moisture, by virtue of which it comes to pass that all the principles act and suffer? Thus, as there are in grammar lengthenings and shortenings of sounds, in music, deep and acute sounds, though not one of them is the privation of the other; we must leave the dry opposed to the moist principles, and the hot to the cold, if we intend to have the effects answerable to reason and what is visible in Nature. Unless, as it was the opinion of the ancient Anaximenes, we will not allow either cold or hot to be in substance, but only to be common passive qualities accompanying the alterations of the matter. For he affirms the contraction and condensation of the matter to be cold; but the rarefication and laxation of it (for by that word he calls it) to be hot. Whence it may not be improperly said, that a man breathes hot and cold at once. For the breath grows cold being compressed and thickened by the lips, but coming out of the open mouth it is hot, as being rarefied by that emission. But for this, Aristotle convinces the same person of ignorance; for that when we blow with the mouth open, we blow hot from our own bodies; but when we blow with compressed lips, we do not breathe forth the air from ourselves, but the air that is before our mouths, being cold, is thrust forward, and lights upon what is next it. 8. But if we must grant that both heat and cold are substances, let us proceed a little farther in our discourse, and enquire what sort of substance is cold, and what is its first principle and nature.