This three-part (Moral) Truth Litmus tells us when a particular (moral/ethical) theory or model is artificial (versus anchored in or descriptive of reality), when that theory or model fails any part of the litmus:
(L1) Part 1: Substantial (Universal Subjectivity, or Objectivity) Aspect: A (moral) theory/model must hold for all or none. (person=person)
(L2) Part 2: Existential Demonstration Aspect: A (moral) theory/model must be demonstrated in reality, not created in divergence from reality. (existential import)
(L3) Part 3: Essential Question Aspect: A (moral) theory/model must define the answer to a question (“How and why should a person(s) be or behave with the other and self (person[s])?”).
If no theory/model passes all three parts of the litmus, there is no (moral) truth.
Being discovered in/by every culture in history is good for part 1 (treat every person/other as a person/self, or the golden rule), but to pass part 2, you need a being whose essence is demonstrated (exists its essence), because no mere human (individually or culturally) does that.
Compare: the three axioms in Theatetus, Newton’s laws of motion, and the three laws of thermodynamics… and my entire thing on harmonic triads. 