Plato refers to this doctrine in several passages of his works. "Not only," says Dacier in his translation, "it is believed that he knew about the Word, eternal Son of God; but also that he knew about the Holy Spirit, for he thus writes to the young Denis: "'I must declare to Archedemus what is much more precious and more divine, and which you so eagerly desire to know; for you sent him to me for this express purpose. According to what he told me, you think that I have not sufficiently explained to you my opinion about the first Principle, therefore I shall write it to you, enigmatically, however, in order that, if my epistle is intercepted at sea or on land, he who will read it will be unable to understand it. All things are around their king; they exist through him, and he is the only cause of good things, second for the second things, and third for the third things.' "In the Epinomis," continues Dacier, "Plato establishes as Principle, the first good, the Word, or intelligence and the soul. The first good is God;... the Word, or intelligence, is the son of this first good, who begets him similar to himself; and the soul, which is the term between the Father and the Son, is the Holy Spirit." Plato had borrowed this doctrine about Trinity from Timee of Locre, who held it from the Italian philosophical school. Marsile Ficin, in one of his remarks on Plato, shows from the testimonies of Jamblic, Porphyre, Plato and Maxim of Tyr, that the Pythagoricians knew also the excellence of the Ternary; Pythagoras himself indicated it in this symbol: Protima to Schema, kai Bema, kai Triobolon. The Jesuit Kirker, dissenting about the unity and trinity of the first Principle, traces vestiges of the doctrine of Trinity up to Pythagoras, and to the Egyptians. St. Augustine himself, though the staunchest defender of the dogma of Trinity, confessed that, among all the nations of the world, a Trinity, nearly similar to the one he believed in, had been held. He added that the Pythagoricians, the Platonicians, and that a great number of Atlantes, Lybian, Egyptian, Persian, Chaldean, Scythian, Gallenses, and Hibernian philosophers, held several dogmas about the unity of the God, Light, and Good, in common with the Church of Rome.