An ontic (real, vs. phenomenal) referent, is an actual reference point one uses as a standard with which to evaluate data.
To an atheist, it would be a measurement, a metric, by which they gauge or determine right from wrong (in the absence of God’s moral law – in which they do not believe). And, since the measurement would be self-derived, it would be subjective.
e.g. – one might say “the laws of man or society are my referent” or “self preservation is my referent”.
But, in the case of the former, where does the inherent value of life come from to ascribe those laws – given that our origins were of non-reasoning, non-intelligent matter only? And, in the latter – suppose that your neighbor determines that in order for him to survive, you must die; now where’s your faith in your referent?
Objective moral values and laws exist only if God exists. Anything else is simply one man’s subjective opinion of how things should be vs. another man’s [again subjective] opinion. And, though some maintain that “man is the measure of all things” – we are compelled to ask “Which man?” – Adolph Hitler, Mother Theresa, Hugh Hefner, the Dalai Lama or Ghengis Kahn…?
So…how do you measure up?