The title which Hilary gave to his work as a whole was certainly De Fide, Concerning the Faith, the name by which, as we saw, Rufinus describes it. It is probable that its controversial purpose was indicated by the addition of contra Arianos; but it is certain that its present title, De Trinitate, was not given to it by Hilary. The word Trinitas is of extraordinarily rare occurrence in his writings; the only instances seem to be in Trin. i. 22, 36, where he is giving a very condensed summary of the contents of his work. In the actual course of his argument the word is scrupulously avoided, as it is in all his other writings. In this respect he resembles Athanasius, who will usually name the Three Persons rather than employ this convenient and even then familiar term. There may have been some undesirable connotation in it which he desired to avoid, though this is hardly probable; it is more likely that both Athanasius and Hilary, conscious that the use of technical terms of theology was in their times a playing with edged tools, deliberately avoided a word which was unnecessary, though it might be useful. And in Hilary’s case there is the additional reason that to his mind the antithesis of truth and falsehood was One God or Two Gods E.g. Trin. i. 17.; that to him, more than to any other Western theologian, the developed and clearly expressed thought of Three coequal Persons was strange. Since, then, the word and the thought were rarely present in his mind, we cannot accept as the title of his work what is, after all, only a mediæval description.