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  • Writer's picture Peter Kupisz

Moral Argument for the Existence of God

Trilemma Version


The moral argument for the existence of God is based on a fact that virtually everyone accepts; namely, that there are objective moral truths that other people should follow. But what makes these moral truths binding on others? There are only three options and since the first two options don’t work, some type of God must exist.

Definition of Objective and Subjective Truths

To understand the moral argument, one first needs to understand how we will define objective and subjective.

Objective truths are those truths which are grounded in a reality outside of the human mind. For example, the statement that "Mt. Everest is the tallest mountain in the world" is objectively true for a few reasons. The physical mountain (i.e. Mt. Everest), that is located in the Himalayas, has been measured against all the other mountains on planet Earth; these measurements indicate that Mt. Everest is the tallest. These facts are not simply ideas that exist in the human mind; they are realities external to the human mind.

In contrast to this, subjective truths are those truths which are grounded in one or more human minds. For example, the statement that "Chocolate ice cream is the best flavour in the whole world" is true because of what certain people think and experience in their minds.

Key Differences Between Subjective and Objective Truths

When it comes to subjective and objective truths, it's important to realize a few key things. When it comes to subjective truths, two or more people can hold contradictory ideas and both can be right. For example, one person can believe that "Chocolate ice cream is the best flavour in the whole world" and another person can disagree by insisting that "Vanilla ice cream is the best." These two statements contradict each other because there can only be one "best." However, these statements can both still be true because they are subjective and therefore relative to each person making the claim.

In contrast to subjective truths, when two people disagree about an objective matter, and they contradict each other, both of them cannot be right. If one person insists that Mt. Everest is the tallest mountain in the world, and another person insists it is not, they both can’t be right.

When it comes to objective truths, it can make sense to disagree with someone and expect him to change his mind, but when it comes to subjective truths, this simply doesn't make sense. If someone thinks that "Blue is the best colour in the whole world," and another person disagrees by claiming that "Yellow is the best," it does not make sense to think that either person is really wrong. People may jokingly disagree, but to seriously claim that another person is wrong about such an issue would demonstrate a fundamental confusion about reality. And if someone were to seriously insist that another person should change their mind on such an issue, that would just be further evidence of this confusion.

To develop the moral argument further, we also need to establish another foundation concerning moral claims.

Commonly Held Moral Claims

Everyone believes that certain moral claims are true. For example, a young lady can get upset when her boyfriend is really late for a date and especially if her boyfriend lacks any good reason for being late. This anger is based on the conviction that people should respect others by trying to be punctual. Many other examples can be given of moral claims that the vast majority of people hold to and live by. For example, the vast majority of people believe the following statements are true:

  1. It's wrong to torture and kill an innocent child.

  2. It's wrong to steal someone’s car.

  3. It's wrong to rape a woman.

  4. It's good to respect your parents.

  5. It's good to be patient.

  6. It's good to help someone who is in dire need.

People also hold to the truth of moral statements concerning societies in other parts of the world as well as societies that existed in the past. Here are some examples of moral claims that are fairly common, but not necessarily held by everyone:

  1. Men in Saudi Arabia need to treat women better.

  2. North Korean dictators should not oppress their citizens.

  3. The Nazis should not have killed millions of Jews.

As previously noted, this second group of statements is not held by everyone. The Nazis didn’t think they were doing anything wrong when they killed millions of Jews. The current dictator of North Korea, Kim Jong Un, surely believes that his actions are right and good, and many people would disagree with a blanket generalisation about men in Saudi Arabia.

If you look hard enough, you can probably also find some people who would disagree with the first group of statements (i.e. 1-6). This is especially true if one considers extreme circumstances and special situations.

The point here is not to try and find any particular moral statement that every single person agrees upon. The point is simply that virtually everyone considers at least one moral claim to be true. Which one(s) they think is/are true will vary (sometimes greatly!), but virtually everyone thinks that at least one moral claim is true.

Nature of Moral Truths

All moral statements have one fundamental aspect to them; they always contain a certain sense of “should (not)” (or “ought (not)”) to them. When someone says that something is “wrong,” “bad” or “evil,” they are saying that people “should not” do those things. On the other hand, when someone says that something is “good” or “right,” they are saying that people “should” do those things.

This “should-factor” is an essential aspect of any moral truth. If someone refers to a moral truth and claims that it does not contain any should-factor, then they are no longer referring to morality. The same thing is true of synonyms like “ethics.”

Are Moral Truths Subjective?

Given the framework established above, it is now worth considering whether moral truths are objective or subjective. That is, are they true because of what we think in our minds or because of some aspect of reality outside our minds? There are only three options here.

If moral claims are true because of what is in our minds, then they are subjective. This is the first of our three options. But recall that when it comes to subjective truths, two things are true:

  1. Contradictory claims can both be correct.

  2. No rational person can seriously think that another person is really wrong and should change their mind.

However, these facts about subjective truths simply don’t match with what we know about the nature of morality. When it comes to moral claims, some people are very wrong and certainly should change their minds. That’s because two moral claims which clearly contradict each other cannot both be right. If someone thinks that it’s good to rape, torture and kill an innocent child, and another person thinks it’s wrong, they cannot both be right.

Everyone regards moral truths as applying to other people regardless of what those other people think. That’s why people disagree so strenuously over them, but none of that makes sense if morality is just based in our minds. It would make as much sense as claiming that someone was very wrong because he liked the colour blue more than yellow.

This conviction comes out most strongly in extreme circumstances. For example, if a psychopath is about to kill your loved ones and he claims that his actions are right, you don’t think he just has a different opinion in his mind. No, you are convinced he is wrong and should not harm your family regardless of what he thinks. This “should not” only makes sense if moral truths are grounded in some aspect of reality that is outside the mind.

Are Moral Truths Objective?

If morality is not subjective, then it must be objective. It must be based in some aspect of reality that exists outside of our minds.

So what aspect of objective reality could moral truths be grounded in? One answer is to point to the physical world which consists of things like rocks, trees, oil, oxygen, distant stars, black holes, subatomic particles and more. This is the second of the three options.

However, this option also has to be rejected because physical things do not have any moral implications for how we should live. For instance, it makes no sense to point at a tree and say that because the tree exists, therefore killing an innocent child is wrong. It also makes no sense to say that because oxygen exists (or black holes or subatomic particles), therefore people should be patient. Physical things simply do not require any moral “shoulds” or “should nots,” so this option must also be rejected.

That leads to the last, and only, other option. There must be some aspect of reality that exists outside of our minds, that is not physical, and which makes moral statements true. This third option requires that morality is objective and thereby explains why people can rationally disagree with others. It makes sense of our deeply held conviction that when it comes to morality, two contradictory claims cannot both be right; and some people are really wrong and should change their mind.

So the moral argument, as presented here, is in the form of a trilemma with the following three options. Moral truths are either:

  1. Grounded in human minds.

  2. Grounded in the physical world.

  3. Grounded in some type of non-physical reality.

Given that the first two options do not adequately explain the nature of morality, there must be some type of non-physical reality that can be called “God.” This God is not necessarily the Christian God; however, the Christian God is certainly one viable option. Identifying who or what this non-physical reality is, is a worthy goal, but it does not determine the success or failure of the moral argument.

There are numerous objections to the moral argument which are listed below. You are invited to click on the "arrow" next to each objection to see the response that expands underneath it.


1.  Objective morality only requires recognizing the right goal: the flourishing of all conscious creatures. You don’t need God to do that.

2. a)  Evolution explains where our morality came from, not God.

b) Our evolutionary past produced our genes, and these genes dictate our morality.

3.  Morality is simply relative to a particular culture or society.

4. Moral absolutes can contradict each other so that disproves objective morality.

5. If morality is objective, then what is the right moral decision in every situation? And what are the right moral standards that everyone should live by?

6. You don’t need God to be a good person; there are many nice atheists in the world.

7. People are motivated to be good by a sense of empathy as well as other factors. They don’t need God or religion to be moral.

8. Animals also display moral behaviour but they don’t need God!

9. You’ve given no real evidence whatsoever to support your claim that morality is objective. You argue that many people agree with your view, but that’s worthless in terms of evidence. Many people “feel” lots of things that turn out to be completely wrong.

10. How can a physical person, with just a physical body, sense these non-physical truths? Are you claiming that people have some sort of spooky “sixth sense” to detect moral “shoulds” and “should nots”? What evidence do you have for this?

11. The moral argument doesn’t prove the existence of the Christian God.

12. The Bible has a lot of bad morality in it.

13. a) The moral argument has been refuted by the Euthyphro dilemma.

b) If there are certain things that are impossible for God, then he cannot be the Christian God because that God can do anything. He is absolutely omnipotent.

c) If God’s nature defines objective morality then are his properties good because he possesses them, or does he possess them because they are good?

14. The identity of the “objective, non-physical reality” cannot be anything like “God” because part of the definition of God is that he/she is conscious and therefore has a mind, but if the “non-physical reality” has a mind, then the moral truths would be in his/her/its mind. This would then present the same problems associated with grounding moral truths in human minds. 

15.  Objective morality can be explained in terms of Platonic forms.

16.  Morality is just subjective because there are no “shoulds” or “should nots” that apply to all people regardless of what they think.


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