Can objective morality exist without God?

Can’t people who don’t believe in God be just as moral as those who do? Why say that the existence of human morality points to the existence of a “Higher Power”?

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If God does not exist then objective moral principles and obligations do not exist. Morality would only be a matter of individual or cultural opinion. But this would mean that torturing babies for fun, rape, & child abuse are not really objectively wrong, and are only a matter of opinion. How likely is it, though, that these atrocities are not really objectively wrong? Can you live with this conclusion? Our deepest intuitions inform us that these actions are horribly wrong.

This is really a summary of a moral argument for God’s existence. Formally it looks like this:

Questions about faith? Bring your doubts
Why would I need faith?: Find some answers

1. If God does not exist, objective moral principles & obligations do not exist
2. Objective moral principles & obligations do exist
3. Therefore, God exists

Consider premise 2. By objective we mean independent of opinion, just like 2 + 2 = 4 is objectively true even if everyone in the world disagreed. Despite people’s claims to being relativists, most people live as if they do believe in objective moral principles & obligations. It’s easy to say there are no objective moral principles & obligations, butit’s much more difficult to live as if there are none.

The judgments we make when ourselves and others are unjustly treated, like in the above atrocities, reveal what we really believe about morality, regardless of what we say we believe. We believe that these atrocities are moral abominations, not just infringements of mere social conventions or personal dislikes. If objective moral principles & obligations do not exist where does our sense of duty and obligation come from?

This leads us to premise 1. If there is no God it is difficult to see how there could be any objective foundation, any universal standard for good and evil. How do you get ethics from only different arrangements of space, time, matter and energy? A purely materialistic universe would be morally indifferent. We would have only individual or cultural opinion, but no objectively binding moral obligations!

Some have suggested that we can provide an objective foundation for morality without appealing to God. Morality has just evolved over the centuries, they suggest, because it promotes human flourishing and survival. Whatever promotes human flourishing and survival is good. Whatever doesn’t promote human flourishing and survival is bad. That is all we need for objectivity in morality, they claim.There is no need for God.

But if God does not exist, the critical assumption that human beings are objectively valuable is not available.Humans, like everything else in the universe, would be just accidental arrangements of atoms, and therefore, we could not justifiably declare that humans are objectively valuable. Furthermore why think the morality of the human species, above all other species, is objectively binding rather than just our opinion?

Moreover, if morality evolved because it produced survival benefits, we would not have objective moral principles & obligations. We would sense that objective moral obligations exist, but they really wouldn’t. Once we’ve figured out that our feeling of morality with regard to say, rape, is just a biological adaptation inculcated into us over millions of years, then we would have no reason to regard rape as objectively wrong anymore.

Since, we know that objective moral principles & obligations do exist, and since they cannot exist without God, it follows that God exists. (modus tollens)

If the God of classical theism existed, an objective foundation for morality would exist. God’s holy and good nature would be the objective standard. God’s nature would be expressed through divine commands which would flow necessarily from his moral nature. Thus we would have objective moral principles & obligations.

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