God’ idea of Himself
God is all knowing and perfect. God therefore has idea of himself. God’s idea of himself is exact and perfect. It is so exact and perfect that it includes everything what God is.
Therefore if God is self existing and eternal, the same with God’s idea of himself is self existing and eternal.
If God is almighty, the same with God’s idea of himself is almighty.
God who generates that perfect idea of himself is Father.
The perfect idea generated is Son.
A God that has no Son is a God who has no perfect and exact idea of himself.