But since no relation can be affirmed of one subject alone, since a predication referring to one substance is a predication without relation, the manifoldness of the Trinity is secured through the category of relation, and the Unity is maintained through the fact that there is no difference of substance, or operation, or generally of any substantial predicate. So then, the category of substance preserves the Unity, that of relation brings about the Trinity. Hence only terms belonging to relation may be applied singly to Each. For the Father is not the same as the Son, nor is either of Them the same as the Holy Spirit. Yet Father, Son, and Holy Spirit are each the same God, the same in justice, in goodness, in greatness, and in everything that can be predicated of substance. One must not forget that predicates of relativity do not always involve relation to something other than the subject, as slave involves master, where the two terms are different. For equals are equal, like are like, identicals are identical, each with other, and the relation of Father to Son, and of both to Holy Spirit is a relation of identicals. A relation of this kind is not to be found in created things, but that is because of the difference which we know attaches to transient objects. We must not in speaking of God let imagination lead us astray; we must let the Faculty of pure Knowledge lift us up and teach us to know all things as far as they may be known.[26] I have now finished the investigation which I proposed. The exactness of my reasoning awaits the standard of your judgment; your authority will pronounce whether I have seen a straight path to the goal. If, God helping me, I have furnished some support in argument to an article which stands by itself on the firm foundation of Faith, I shall render joyous praise for the finished work to Him from whom the invitation comes. But if human nature has failed to reach beyond its limits, whatever is lost through my infirmity must be made good by my intention. [26] Cf. _Cons._ v. pr. 4 and 5, especially in pr. 5 the passage "quare in illius summae intellegentiae acumen si possumus erigamur." ANICII MANLII SEVERINI BOETHII V.C. ET INL. EXCONS. ORD. PATRICII AD IOHANNEM DIACONVM VTRVM PATER ET FILIVS ET SPIRITVS SANCTVS DE DIVINITATE SVBSTANTIALITER PRAEDICENTVR