Certainly if you are not a Trinitarian, this is a problem. I am not using philosophy to prove something, but I am using logic, which is the way people think and solve problems. If you reject that, then we are in deep trouble.
Trinitarian beliefs developed from arguments against assorted Gnostic beliefs that degraded the One God within Christianity.
Factually that is incorrect. The Trinity has its roots in the struggle against Arius, who said that the Father was superior to the Son. Athanasius said that the Son was coequal to the Father, because They are both eternally and fully God. In this respect and all other respects the Trinity affirms the Unity of God.
Gnosticism comes from the Greek gnosis, meaning knowledge. It developed from teachers who said that they had special knowledge of God outside the Bible. They wrote the gnostic “gospels” to justify this special knowledge, which they dais came from the risen Christ, Who was different from the historical Jesus.
Of course the Trinity does not solve all the problems and of course gnostics still survive. I live across for a Christian Science Church. They believe that true knowledge or gnosis or science as explained by May Baker Eddy dhows that sin, evil, sickness, and death do not exist.
The early Christian population of gentiles understood as reality the Greek concept of body, soul, and spirit. They segregated the inner workings of each human therefore it was okay to segregate God into three as long as they insisted that the Triune God was also one.
What is the source of this information? It would seem that most people of this time would be soul/body dualists after Socrates and Plato.
No one has yet put a spirit, or God, under a microscope with any form of methodology that can be repeated.
No one has put a thought or ideas under a microscope with any form of methodology that can be repeated. First we have deal with the mind/body question. Just because the mental and rational is different from the physical does not mean it does not exist, which is want monists claim.
You use the word “idiocentric,” where most people would use “egocentric.” If you mean based on the id or the sensual and instinctual, I do not know any id which focused a microscope on anything, just rational egos who engage in efforts to understand ourselves and our world.
Of course these efforts of understanding are not perfect. We are imperfect limited beings. Indeed if Reality were simple and obvious, rather than complex and requiring research, than would be great evidence for a uniform, simple monistic universe, which does not exist. Humans cannot exist and flourish in a complex, but unified universe unless they share that complex, but unified nature.
It seems strange to me and to most people that some people can use their minds to declare that their minds so not exist.
The universe is one like its Creator is One.
I quite agree. Where we disagree is that I and most people, although truth is not based on majority rule, understand the Creator as Trinity, Three and One, which is back where we started, but at least we understand each other.