X.  What then?  Is the Spirit God?  Most certainly.  Well then, is He Consubstantial?  Yes, if He is God.  Grant me, says my opponent, that there spring from the same Source One who is a Son, and One who is not a Son, and these of One Substance with the Source, and I admit a God and a God.  Nay, if you will grant me that there is another God and another nature of God I will give you the same Trinity with the same name and facts.  But since God is One and the Supreme Nature is One, how can I present to you the Likeness?  Or will you seek it again in lower regions and in your own surroundings?  It is very shameful, and not only shameful, but very foolish, to take from things below a guess at things above, and from a fluctuating nature at the things that are unchanging, and as Isaiah says, to seek the Living among the dead. Isa. viii. 19.  But yet I will try, for your sake, to give you some assistance for your argument, even from that source.  I think I will pass over other points, though I might bring forward many from animal history, some generally known, others only known to a few, of what nature has contrived with wonderful art in connection with the generation of animals.  For not only are likes said to beget likes, and things diverse to beget things diverse, but also likes to be begotten by things diverse, and things diverse by likes.  And if we may believe the story, there is yet another mode of generation, when an animal is self-consumed and self-begotten. i.e. the Phœnix.  Hdt., ii. 37.  There are also creatures which depart in some sort from their true natures, and undergo change and transformation from one creature into another, by a magnificence of nature.  And indeed sometimes in the same species part may be generated and part not; and yet all of one substance; which is more like our present subject.  I will just mention one fact of our own nature which every one knows, and then I will pass on to another part of the subject.