We have three axioms:
1) There is no thought without a thinking subject, and vice versa, there is no thinking subject without a thought.
2) Nobody can be his own thought, since it implies a contradiction between subject and object. The subject must be always greater than the object.
3) Nothing is without an activity.
And I infer the following:
a) "The truth is the truth" is the first truth.
b) It can't exist without an activity, so it must be thought by someone.
c) The Father thinks it, and that truth is the Son.
d) The Father is greater than the Son. Nevertheless, they are the same reality, as far as there is no thought without a thinking subject and there is no thinking subject without a thought.
e) The act of thinking itself is the Holy Spirit.
f) So, I understand the Trinity as "The Thinker (Father) in the Act of Thinking (Holy Spirit) the Thought (Son)".
* * *
I.
"'The truth is the truth' is true" is a part of the set of truths, since it is true, but only in a tangencial way, as far as it doesn't need any other truth as a fundament and it exists necessarily.
Every truth must fulfill three properties: 1) coherence with itself, 2) coherence with other truths and 3) inference from other truths. God only fulfills 1) and 2). Thus, it is part and it isn't part of the set of truths.
I'm inclined to think that God lacks a basis. If he had one, it would be someting logically previous to God, simpler than him, more elemental and, therefore, greater. In other words: truth is abstractive, that is to say, negative. That which is more composed is more contingent (it has more conditions of existence), innecessary or superfluous than that which is simpler.
II.
Trinity solves the following problem: How is possible the "creatio ex nihilo" of material things from the divine, inmaterial plenitude?
Gnostics proposed a prolation or pronunciation of God to the material world. Before this prolation occurred, it would have been some unavoidable Silence and Abyss between the Creator and the creature.
Catholic ortodoxy opposes to this conception the coeternity of the Word, engendered from the same substance of God before any time was. The divine Verb is, previous to its incarnation, the invisible Image of the Creator, but it is also the invisible or rational image of every creature. It acts as a mediator between both realities.
Truth would be inactive and it could not create anything if it wasn't, at the same time, expansive. The self-sufficient truth, then, also implies the true. So, Trinity can be condensed in this sentence: "'The truth (Father) is the truth' (Son) is true (Holy Spirit)". It doesn't exist a simpler way to express the first true proposition, the unfounded fundament of everything.
If Islam denies that this proposition is true, then Islam is wrong and leads to falsity, which can't be attributed to God, but to the doctrines of men. If Islam thinks that there is a simpler procedure in order to express this first true proposition, may Islam show it as soon as possible.
III.
1) God didn't create the world arbitrarily, but according to ideas supported by the Truth.
2) However, the Father can't be fully identified with that coeternal ideas, since they presuppose a creative intention and a preceptive order. In the other hand, the will of Creation is an accidental one compared to the eternal, unengendered and self-subsistent potency of God.
Plus, God's providence depends on his will, while his will doesn't depend on providence.
Finally, ideas are naturally conceivable, but God is absolutely inconceivable.
3) Christ (the Son) is the sum of all the ideas that tend to Creation, and he is also its engendered fundament: the Good, the Truth, the Life.
God, nevertheless, is Christ's fundament.
4) God, an absolutely undetermined potency, engenders the Truth, an absolutely determined potency. At last, it engenders the Spirit, which is the infinite and absolutely determined act, as far as it is coherent with the Truth.
Cheers.
Daniel.
Theological Miscellany (in Spanish):http://www.miscelaneateologica.tk 
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