numbers in the bible

So why on earth are there three parts to the trinity and not four? What fundamental property of systems caused that?

First of all, God created numbers so he could have chosen whatever he wanted. God was first, function stuff came later, so we can't ask ourselves how the 'more fundamental' idea of systems disproves God. He created them.

Honestly, I don't know much about this number thing. It has effects in the real world though. Why do most people have three points to their English papers and speeches? Color wheels, mathematical stability, etc.

Special numbers: 1,2,3,4,6,7,10, 12,40,1000
Note: 6 only comes from 666. Also 40 appears in different powers of ten and other units, so we can simply combine it with 4.

Let me just say something about revelations: It has 3 subsequently tiered sets of 7 plague type stuff each starting with 4 similar plagues, 2 odd ones, and 1 more which contains the next 7. There are 7 lamps/spirits/churches of God, 2*12 = 24 elders around the throne, 12^2*1000 = 144,000 martyrs in white robes, 3 frog-type demons, 2 evil beasts, 10 horns/kings on the dragon, 3 beings thrown into the lake of fire, 3 6's = 666 on bad peoples foreheads or palms, 1000 years of JC reigning, and 1 God doing it all. Whooooe!

1 is just special. No comment.
2 does not appear much in the bible but does in our bodies, in relationships, in binary, and other places. There are 2 witnesses in revelations.
3 I just mentioned shows up everywhere. I think it means 'complete' in a functional sense.
4 This I will explain more. People generally think it denotes judgment. 400 years in Egypt, 40 years in the desert, 40 days of rain. But it's also a commitment idea. 40 days of fasting. 40 days of Elijah seeking God through the desert. And I wrote something down in my notes about "Moses tablets = seek". Maybe a dedication or purification idea too. There are 4 beasts in Daniel corresponding to four upcoming civilizations. There are four-sided heads of the hovering animals in Ezekiel.
6 I looked this up, and there are an excess of appearances of 6 in the bible regarding years of labor, amounts of Jewish people, construction of the temple, and other stuff - weird. Anyway, the only think I remember is 666. It might mean evil - maybe not. 12/2 = 6. Leah and Rachel both bore 6 sons to Joseph. God spent 6 days making the earth and on the seventh he rested. The only reason we think 6 is evil is because of 666.
7 This might mean holy. Spirits of God, churches, days of creation, days in a week, etc. I wonder why we don't also associate it with judgment because of the 3 sets of 7 plagues???
10 Plagues in Egypt, kings/horns on the dragon/devil head. Also a general base for making numbers larger. (see the number 4)
12 I'm thinking 'complete' in a human sense. 12 tribes, 24 elders, 144k martyrs. etc.
1000 is just a big number. 1 day is like a thousand years. They probably don't mean exactly, they just mean a LONG time. JC reign in final kingdom.

Math: 3+4 = 7 = 4+2+1. 10 = 7+3. 2*6=12...you get the idea.

Conclusion - none. You figure it out. I'm too tired.