15. Moreover, if there is a diminished being or being in a qualified sense, there is being in an unqualified sense: because being in a qualified sense can neither exist nor be understood unless it is understood through being in an unqualified sense, nor can diminished being be understood except through perfect being, just as privation is not understood except through possession. If, therefore, every created being is being according to a part, while only uncreated being is being in an unqualified sense and perfect: it is necessary that every difference of being implies and concludes that God exists.
16. Moreover, if there is a being for the sake of another, there is a being for the sake of itself, otherwise nothing would be good; but a being for the sake of itself is none other than that being than which nothing is better, which indeed is God himself: therefore, since the universe of other beings is ordered toward that being, the universe of beings implies God both according to being and according to understanding.
17. Moreover, if there is a being by participation, there is a being by essence: because participation is not spoken of except in relation to something essentially possessed by someone, since everything by accident is reduced to what is by itself; but any being other than the first being, which is God, has being by participation, while that alone has being by essence: therefore, etc.
18. Moreover, if there is a being in potency, there is a being in act: because potency is never reducible to act except through a being in act, nor would there be potency unless it were reducible to act: if, therefore, the being that is pure act, having nothing of possibility, is none other than God; it is necessary that everything other than the first being implies that God exists.
19. Moreover, if there is a composite being, there is a simple being: because the composite does not have being from itself, therefore it is necessary that it receive its origin from the simple: but the most simple being, having nothing of composition, is none other than the first being: therefore every other being implies God.
20. Likewise, if there is mutable being, there is immutable being: because, as the Philosopher proves, motion proceeds from a being at rest and for the sake of a being at rest: if therefore the wholly immutable being is none other than that first being, which is God, while other created things, by the very fact that they are created, are mutable: it is necessary that God's existence be inferred from any difference of being whatsoever.
From these ten necessary and manifest suppositions, therefore, it is inferred that all the differences or parts of being imply and proclaim that God exists. If therefore every such truth is an indubitable truth: then it is necessary that God's existence be an indubitable truth.
This same thing is shown by a third way as follows. Every truth which is so certain that it cannot be thought not to be is an indubitable truth: but that God exists is of this kind: therefore, etc. The first is self-evident; the second is shown in multiple ways.
21. For Anselm, in chapter four of the Proslogion: "Good Lord, I give thanks to you, because what I formerly believed by your gift, I now so understand by your illumination, that even if I were unwilling to believe that you exist, I could not fail to understand it."
22. Likewise, Anselm proves this same thing as follows: God is that than which nothing greater can be thought: but that which is such that it cannot be thought not to exist is more truly than that which can be thought not to exist: therefore, if God is that than which nothing greater can be thought, God cannot be thought not to exist.
23. Likewise, a being than which nothing greater can be thought is of such a nature that it cannot be thought unless it exists in reality; because if it exists in thought alone, then it is not a being than which nothing greater can be thought: therefore, if such a being is thought to exist, it is necessary that such a being exist in reality, such that it could not be thought not to exist.
24. Likewise, Anselm: "You alone are whatever it is better to be than not to be"; but every indubitable truth is better than every dubitable truth: therefore, to God it must be attributed to exist indubitably rather than dubitably.
25. Likewise, Augustine says in the Soliloquies that no truth can be seen except through the first truth: but the truth through which every other truth is seen is the most indubitable truth: therefore, that God exists is a truth not only indubitable, but also than which nothing more indubitable can be thought: therefore, it is such a truth that it cannot be thought not to be.
26. Likewise, he proves this same thing as follows: whatever can be thought can be stated: but in no way can it be stated that God does not exist without its being stated, along with this, that God exists. And this is evident as follows: because if no truth exists, it is true that no truth exists: and if this is true, something is true; and if something is true, the first truth exists: therefore, it cannot be stated that God does not exist, nor thought.
27. Again, the more prior and universal a truth is, the more known it is; but this truth, by which the first being is said to exist, is the first of all truths both in reality and in the order of understanding: therefore it is necessary that it be the most certain and most evident. But the truths of axioms or common conceptions of the mind are so evident on account of their priority that they cannot be thought not to exist: therefore no intellect can think that the first truth does not exist, or doubt concerning it.
28. Again, "no proposition is truer than that in which the same thing is predicated of itself"; but when I say that God exists, being said of God is entirely the same as God, because God is His very own being : therefore no proposition is truer and more evident than that by which God is said to exist: therefore no one can think it to be false, or doubt concerning it.
29. Again, no one can be ignorant that this is true: the best is the best, or think it to be false; but the best is the most complete being, and every most complete being by that very fact is a being in act: therefore if the best is the best, the best exists.
Similarly it can be argued: if God is God, God exists; but the antecedent is so true that it cannot be thought not to be: therefore that God exists is an indubitable truth.
But on the contrary it is objected that God's existence can be thought not to be and that it is a dubitable truth. That it can be thought not to be is shown as follows.
1. The Psalm: The fool has said in his heart: there is no God; but to say in the heart is to think: therefore that God does not exist can be thought, at least by the fool.
2. Again, Damascene, in the first book, chapter three: "The pernicious malice of human nature has so prevailed as to lead some into the most irrational and worst of all evils, the abyss of perdition, so that they say that God does not exist": therefore at least by malicious men it can be thought that God does not exist.
3. Again, an idol is nothing, as is said in First Corinthians, chapter eight: therefore to think that God is an idol and that God does not exist is the same thing: but it is thinkable and is sometimes thought that God is an idol: therefore it is thinkable that God is nothing.
4. Again, what can be signified can also be thought: but it can be signified that God does not exist, as by this statement: God does not exist: therefore it can be thought.
5. Again, an objection is raised against Augustine's argument: when he proves that from this proposition "no truth exists," it follows that some truth exists. For if this proposition is true: "some truth exists," it therefore has a contradictory: but no contradictory entails or posits, but rather negates its contradictory: therefore from the claim that no truth exists, it is not concluded that some truth exists.
6. Item. It is objected against the argument of Anselm, by which he proves that God exists through the fact that the being than which nothing greater can be thought exists in thought: because by equal reasoning it can be thought, if someone thinks of an island than which nothing greater can be thought, that that island exists in reality: therefore if that argument is worthless, the argument which Anselm makes is therefore worthless.