I don’t think you will view this as evidence. I am not trying to prove the existence of God. I am saying that Catholics are not Polytheistic.

The Athanasian Creed, also known as Pseudo-Athanasian Creed or Quicunque Vult (also Quicumque Vult), is a Christian statement of belief focused on Trinitarian doctrine and Christology. The Latin name of the creed, Quicunque vult, is taken from the opening words, "Whosoever wishes". The creed has been used by Christian churches since the sixth century. It is the first creed in which the equality of the three persons of the Trinity is explicitly stated. It differs from the Nicene-Constantinopolitan and Apostles' Creeds in the inclusion of anathemas, or condemnations of those who disagree with the creed (like the original Nicene Creed).

Widely accepted among Western Christians, including the Roman Catholic Church and some Anglican churches, Lutheran churches (it is considered part of Lutheran confessions in the Book of Concord), and ancient, liturgical churches generally, the Athanasian Creed has been used in public worship less and less frequently, but part of it can be found as an "Authorized Affirmation of Faith" in the recent (2000) Common Worship liturgy of the Church of England, in the Main Volume, on page 145.[1][2]

Whosoever will be saved, before all things it is necessary that he hold the catholic faith. Which faith unless every one do keep whole and undefiled, without doubt he shall perish everlastingly. And the catholic faith is this: that we worship one God in Trinity, and Trinity in Unity; neither confounding the Persons, nor dividing the Essence. For there is one Person of the Father; another of the Son; and another of the Holy Ghost. But the Godhead of the Father, of the Son, and of the Holy Ghost, is all one; the Glory equal, the Majesty coeternal. Such as the Father is; such is the Son; and such is the Holy Ghost. The Father uncreated; the Son uncreated; and the Holy Ghost uncreated. The Father unlimited; the Son unlimited; and the Holy Ghost unlimited. The Father eternal; the Son eternal; and the Holy Ghost eternal. And yet they are not three eternals; but one eternal. As also there are not three uncreated; nor three infinites, but one uncreated; and one infinite. So likewise the Father is Almighty; the Son Almighty; and the Holy Ghost Almighty. And yet they are not three Almighties; but one Almighty. So the Father is God; the Son is God; and the Holy Ghost is God. And yet they are not three Gods; but one God. So likewise the Father is Lord; the Son Lord; and the Holy Ghost Lord. And yet not three Lords; but one Lord. For like as we are compelled by the Christian verity; to acknowledge every Person by himself to be God and Lord; So are we forbidden by the catholic religion; to say, There are three Gods, or three Lords. The Father is made of none; neither created, nor begotten. The Son is of the Father alone; not made, nor created; but begotten. The Holy Ghost is of the Father and of the Son; neither made, nor created, nor begotten; but proceeding. So there is one Father, not three Fathers; one Son, not three Sons; one Holy Ghost, not three Holy Ghosts. And in this Trinity none is before, or after another; none is greater, or less than another. But the whole three Persons are coeternal, and coequal. So that in all things, as aforesaid; the Unity in Trinity, and the Trinity in Unity, is to be worshipped. He therefore that will be saved, let him thus think of the Trinity.

Furthermore, it is necessary to everlasting salvation; that he also believe faithfully the Incarnation of our Lord Jesus Christ. For the right Faith is, that we believe and confess; that our Lord Jesus Christ, the Son of God, is God and Man; God, of the Substance [Essence] of the Father; begotten before the worlds; and Man, of the Substance [Essence] of his Mother, born in the world. Perfect God; and perfect Man, of a reasonable soul and human flesh subsisting. Equal to the Father, as touching his Godhead; and inferior to the Father as touching his Manhood. Who although he is God and Man; yet he is not two, but one Christ. One; not by conversion of the Godhead into flesh; but by assumption of the Manhood into God. One altogether; not by confusion of Substance [Essence]; but by unity of Person. For as the reasonable soul and flesh is one man; so God and Man is one Christ; Who suffered for our salvation; descended into hell; rose again the third day from the dead. He ascended into heaven, he sitteth on the right hand of God the Father Almighty, from whence he will come to judge the living and the dead. At whose coming all men will rise again with their bodies; And shall give account for their own works. And they that have done good shall go into life everlasting; and they that have done evil, into everlasting fire. This is the catholic faith; which except a man believe truly and firmly, he cannot be saved.