Objective morality means that morality is not sourced in human opinion and is correct no matter what anybody thinks.
Objective morality is a principle. Its content is another matter. That is the difference between, "Right and wrong are really right and wrong" and "Murder is wrong."
If Objective Morality Were a Person and Committed Murder
If “objective morality” were an actual person and did something morally wrong—like murder—it creates a paradox:
• If the act is objectively moral simply because this being did it, then morality becomes might-makes-right, not objective truth.
• If the act is objectively immoral, then “objective morality” is capable of violating the very standards it represents, meaning it isn’t truly identical to what we call moral truth.
• This mirrors classic debates about whether moral laws come from an authority (divine command theory) or exist independently (moral realism).
This would suggest:
• The personified being isn’t actually “objective morality,”
• Or morality cannot be coherently personified.
Those can be safely dismissed for if objective morality is real, whatever that means, that it is not abstract, then in theory it can be a person. Interestingly, it seems to many that it is a sort of communication about certain behaviours. It is not totally unlike a person. Even if it can't be a person, it is still a valid thought experiment.
There is another suggestion.
• Or morality isn’t what we thought it was.
That would mean it is not very relatable to us as human persons. It would not even agree with itself.
THOUGHT EXPERIMENT: Objective morality is seen as communication even if it does not communicate to anybody. It communicates say that murder is wrong.
What if it wrote a sign? "I am right that certain actions are right or wrong. This statement is false." This is a form of the notorious Liar's Paradox.
If morality is imagined as a real communicator, then:
It could communicate to itself
But only if we imagine it as a self-interpreting agent
Which creates paradoxes/contradictions similar to self-referential logic systems.
If morality “communicates,” and we have no guaranteed access to its true content, then the only thing that could “receive” morality’s message is morality itself. So the system becomes self-referential. Self-reference by itself is not wrong — but self-reference combined with a liar-paradox would make the moral system inconsistent.
THOUGHT EXPERIMENT:
Suppose objective morality were a person. Let’s call him John. Imagine that John must act without relying on the knowledge that morality is objective, or the knowledge of what objective morality ordinarily forbids. He has to forget one of these - erased from his memory.
He kills somebody in cold blood.
Objective morality normally forbids murder. Yet, in this hypothetical, John as objective morality has murdered.
Is it a contradiction?
Reply: No John is a person and is compelled by his own perspective to murder. From the standpoint of objective moral truth: murder is wrong. From the standpoint of John-as-subjective-believer: failing to act on what he thinks morality requires is wrong. So the “paradox” or “apparent contradiction” arises from conflicting perspectives, not from objective morality simultaneously asserting two directly contradictory commands. In other words: There is no formal logical contradiction.
What? That reply forgets that this is not John as John but John as in objective morality. He has not made a mistake.