The Moral Argument for the Existence of God

The Cosmological argument from Design asks why anything should exist. The Teleological (argument from design) argument discusses the need for a designer to explain all the intricate structure and design experienced in life. The moral argument similarly asks how it is and who it is that puts morality into our conscience. Let’s start with something simple: you’ve probably felt that tug inside that says, “I should do the right thing,” even when no one is watching. That feeling isn’t just a mood—it’s more like a command. The moral argument says that if those “shoulds” and “shouldn’ts” are real for everyone, then they come from somewhere big enough to make them matter. The idea is that objective moral values (like “kindness is good” and “cruelty is wrong”) and real duties (like “help people in trouble”) make the most sense if there’s a perfect source of goodness behind them: God.

Think of it like this: if right and wrong are real and not just opinions then there’s a reason they’re real. The moral argument claims that Objective morals exist. Some things are really right or really wrong, no matter what people think. They need a solid foundation. If moral rules are for everyone, what gives them authority? God is the best explanation. God’s perfect goodness explains why kindness is good, and God’s will explains why helping others is something we really should do.

That’s the core. If you believe that “torturing someone for fun is wrong” is true for everyone, not just your group, you’re already pointing to a standard beyond human taste or culture.

Historical Development

Immanuel Kant argued that doing the right thing isn’t about getting rewards. It’s about obeying duty because it’s right. He thought our deep commitment to duty points to a bigger, just order that makes moral seriousness make sense. In the Groundwork, he famously wrote: “Act only according to that maxim whereby you can at the same time will that it should become a universal law,” which shows how he sees moral rules as binding for everyone, not just for me. Later, reflecting on the weight of morality, Kant said, “Two things fill the mind with ever new and increasing admiration and awe… the starry heavens above me and the moral law within me,” linking the moral law to something objective and grand. He argued it’s reasonable to postulate God and immortality so that virtue and deserved happiness can ultimately fit together in a just universe.

C.S. Lewis made the same idea feel close to everyday life. He said our built-in sense of “ought” looks like a real moral law, and laws usually have lawgivers. In Mere Christianity, he argued that this moral law isn’t just a private feeling: “You find out more about God from the Moral Law than from the universe in general… the Moral Law is a real clue to the meaning of the universe.” He also explained why instincts alone can’t be our guide: “The Moral Law tells us the tune we have to play: our instincts are merely the keys.” For Lewis, the fact that people everywhere argue about what’s right means they recognize a standard above them, even when they break it.

Hastings Rashdall said moral truths are objective, rooted in what is truly good, rather than invented by feelings or power. He argued that right actions depend on promoting genuine goods like justice and character, and those goods are recognized by reason. Rashdall thought this makes most sense if goodness is grounded in a perfect mind: God. In his words, the right is “that conduct which produces the greatest good,” but the good itself is not created by will; it is apprehended by reason and reflects a moral order we discover, not make up.

W. R. Sorley was impressed to consider the personalness of morality. If morality is truly authoritative and purposive, it points beyond impersonal facts to a personal source. He argued that the “moral order” looks like it belongs to a moral mind, not a blind process. For Sorley, the binding “ought” we experience suggests a law that isn’t just there it’s given. That makes sense, he said, if the foundation of morality is the character of a personal God, whose goodness grounds value and whose will grounds duty.

Together, these thinkers develop deep connections between the existence of morality and its source. The cosmological argument compels us to consider the existence of a God simply because things exist. Similarly, the moral argument recognizes the universal impact and nature of morality on all societies in all times and considers where does this law come from. Morality feels universal and authoritative. We live as if some things are really right and wrong. Kant shows why duty needs a just horizon. You see someone collapse. No law forces you to help, but you feel you must. Where does that “must” come from if it’s more than a vibe? The moral argument points to a real moral law and a real Lawgiver. Genocide or human trafficking don’t feel “just unpopular.” They feel wrong for anyone, anywhere, at any time. That sounds like a universal rule, not a local opinion.

Lewis continues even more on this trajectory examining why our everyday “ought” looks like a real law. It is reasonable to see there is a moral law in man. It seems built into our conscience as opposed to taught. Conscience is like a compass. A compass works because there’s a real magnetic field. If your conscience points toward “moral north,” it makes sense to think there’s a real moral field too. It indicates a objective moral existence outside of man and imposed on him. Objective moral values and duties make the most sense if there is a perfect source of moral laws, God.

Opposition

It will be helpful now to address just a few common arguments in opposition to the moral argument presented. Evolutionists deny the personal need for a moral law giver in the same way they need no designer to build an intricately designed system for existence. They suggest evolution can instill morality. Evolution might explain why we feel certain moral instincts (like cooperation) but this must be distinguished from morality. Morality is more than instinct. Instincts are impulsive and reactionary while morals need reflection. Ethical reasoning and higher awareness are needed for morality but not with instincts. Morality is further distinguished by a need to choose. If morality were instinct the variation of choice among morals would be scant. But even if evolution were the source of morality, it doesn’t tell us whether those moral claims are actually true. Explaining where a belief comes from isn’t the same as proving it’s correct.

Let’s look now at another opposition that states different cultures disagree about morals. While this is true these disagreements do not mean there’s no truth. Cultures disagree about lots of things, art, laws, even math, but that doesn’t make truth disappear. Across cultures, we still find fixed points that cannot be excused as mere opinion and preference. Universal virtues and vices seem to exist in all cultures. Cruelty, betrayal, and injustice are widely condemned and make this claim inadequate. Anyone arguing in this way must recognize that if it’s true there should be no objection to their being murdered to satisfy a status quo in support of this moral argument. This statement demonstrates at once how obvious it becomes when our rights are violated that morality is universal.

Finally, it is frequently objected that God is not needed for morals to exist. People can be moral without believing in God. But the argument asks a deeper question: what makes moral truths real and binding for everyone? If there is no moral law giver everything becomes arbitrary. Secular ideas can describe moral systems well, but they often end up borrowing assumptions like universal human dignity. These universal claims do not exist without a source that defines them. It seems more reasonable to assume a source than to suggest they arrive at random. It is more reasonable indeed to recognize they come not from thin air but from the goodness in God’s nature. God’s morality is not random. The moral law is an expression of God’s goodness and fit best the explanation of a perfect source behind them.

This argument is persuasive and valuable in ways other arguments for God’s existence are not. It applies directly to the real world and is personal to us. We talk about human rights like they’re for everyone. We say every person has equal worth. We insist that justice should win, even when it’s hard. Those ideas carry a “must,” not a “maybe.” The moral argument explains why that “must” makes sense: if people bear the image of a perfectly good God, then their dignity is real and universal; if God’s goodness is the standard, then justice isn’t just preferred it’s required. This way of seeing the world encourages courage, mercy, and hope. It is a reality derived from the maker of reality.

Conclusion

If you trust your conscience when it tells you to help, to be honest, to be brave, then you already trust something bigger than your feelings. You do not need to believe in God or morality to be bound in its existence. The moral argument says that “something bigger” is best explained by a perfect source of goodness, God. That makes sense of why right and wrong feel real, why duty feels like it matters, and why hope for justice isn’t wishful thinking but a pointer to the deepest truth. The world seeks desperately to deny God often to deny this very morality. Greed, selfishness and cruelty oppose not just the morality inherent in each of but the God who placed it there. There is not authority to reject these vices if they are not based in God. It is often the case we want to rationalize a morality apart from God but in this we create a landscape where nothing is wrong. The outcome alone is a testament to the deceptive nature of denying a moral law giver and the need to both recognize and submit to his moral law.

1. Immanuel Kant, Critique of Practical Reason (1788), on the “highest good” and the postulates of practical reason.

2. C.S. Lewis, Mere Christianity (1943), Book I on the “Law of Human Nature.”

3. Hastings Rashdall, The Theory of Good and Evil (1907);

4. W.R. Sorley, The Moral Life and the Moral Law (1913)

5. Immanuel Kant, Groundwork of the Metaphysics of Morals (1785); Critique of Practical Reason (1788).

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