Thomas Aquinas

“ God made every creature proportionate to the universe which He determined to make. Therefore had God resolved to make more angels or more natures of things, He would have impressed more intelligible species in the angelic minds; as a builder who, if he had intended to build a larger house, would have made larger foundations. ”

“ So the nature of an angel does not hinder him from knowing the other angelic natures, since both the higher and lower bear affinity to his nature, the only difference being according to their various degrees of perfection. ”

“ The nature of cause and effect does not lead one angel to know another, except on account of likeness, so far as cause and effect are alike. Therefore if likeness without causality be admitted in the angels, this will suffice for one to know another. ”

“ Now, for the form to be the principle of the action, it makes no difference whether it be inherent in something else, or self-subsisting; because heat would give forth heat none the less if it were self-subsisting, than it does by inhering in something else. So therefore, if in the order of intelligible beings there be any subsisting intelligible form, it will understand itself. And since an angel is immaterial, he is a subsisting form ”

“ We have no knowledge of single corporeal things, not because of their particularity, but on account of the matter, which is their principle of individuation. Accordingly, if there be any single things subsisting without matter, as the angels are, there is nothing to prevent them from being actually intelligible. ”

“ They proceeded into the angelic mind in such a way, that God impressed upon the angelic mind the images of the things which He produced in their own natural being. Now in the Word of God from eternity there existed not only the forms of corporeal things, but likewise the forms of all spiritual creatures. ”