Cosmological
Arguments from Causation
Teleological
Arguments from Design
Moral & Rational
Arguments from Morality & Reason
The Moral Argument
(P1) If God does not exist, objective moral values and duties do not exist. (1) What "objective" morality means. - When we say moral values and duties are objective, we mean they are true or binding independently of what any person or culture believes. - Nazi anti-Semitism was morally wrong even though the Nazis believed it was good. It would still have been wrong even if the Nazis had won World War II and convinced everyone it was right. - The difference is clear when we contrast subjective with objective claims. "Chocolate ice cream is better than vanilla" depends on personal taste. "Torturing children for fun is wrong" is true regardless of anyone's opinion. (2) The distinction between moral values and moral duties. - Moral values concern what is good or bad, the worth of something. Moral duties concern what is right or wrong, what we are obligated to do. - It would be good for someone to become a doctor, but that does not mean they have a duty to become a doctor. They could become a teacher or a firefighter and those would also be good choices. - Sometimes all available options are bad, as in genuine moral dilemmas, but a person still has a duty to choose one. The badness of the outcomes does not dissolve the obligation. Values and duties are related but distinct moral categories requiring different explanations. (3) On naturalism, what grounds objective moral values? - If atheistic naturalism is true, humans are accidental byproducts of nature, evolved recently on an unremarkable planet in a vast and mindless universe, doomed to perish individually and collectively in cosmological terms. - Richard Dawkins captured the logical conclusion of this picture in River Out of Eden (1995): "The universe that we observe has precisely the properties we should expect if there is, at bottom, no design, no purpose, no evil, no good, nothing but pitiless indifference." - Writing with biologist E.O. Wilson, philosopher Michael Ruse was candid about the implications: "The position of the modern evolutionist is that humans have an awareness of morality because such an awareness is of biological worth. Morality is a biological adaptation no less than are hands and feet and teeth. Considered as a rationally justifiable set of claims about an objective something, ethics is illusory. I appreciate that when somebody says 'Love thy neighbor as thyself,' they think they are referring above and beyond themselves. Nevertheless, such reference is truly without foundation. Morality is just an aid to survival and reproduction, and any deeper meaning is illusory." (Michael Ruse and E.O. Wilson, "The Evolution of Ethics," New Scientist, 1985) - Given this picture, there is no principled reason why human well-being is objectively good rather than insect well-being or rat well-being. What makes humans morally special compared to any other species of animal? (4) Moral duties require a personal source of obligation. - Moral duties involve genuine obligation: we ought to do some things and ought not do others. But obligation is inherently relational and requires a personal source. - Richard Taylor explains the problem clearly in Ethics, Faith, and Reason (1985): "A duty is something that is owed. But something can be owed only to some person or persons. There can be no such thing as duty in isolation. The idea of political or legal obligation is clear enough... Similarly, our moral obligations can be understood as those that are imposed by God. But what if this higher-than-human lawgiver is no longer taken into account? Does the concept of a moral obligation still make sense? The concept of moral obligation is unintelligible apart from the idea of God. The words remain but their meaning is gone." - On naturalism, there is no personal authority behind moral demands. They are simply strong feelings produced by evolutionary pressure, with no one to whom they are owed and no genuine lawgiver who issues them. (5) On theism, God grounds morality at three distinct levels. - Moral values are rooted in God's perfectly good nature. God is essentially loving, just, kind, generous, faithful, and impartial. His nature is the standard by which all else is measured. Love, generosity, self-sacrifice, justice, and equality are objectively good because they reflect God's nature. Hatred, selfishness, cruelty, oppression, and discrimination are objectively evil because they contradict it. - Moral duties are rooted in God's commands. These commands flow necessarily from His nature and are not arbitrary. They constitute our obligations as God's creatures. The obligation is real because it comes from a real personal authority, namely our Creator. - Moral accountability is grounded in God's justice. On theism, evil and wrongdoing will ultimately be answered for, and righteousness will be vindicated. Acts of self-sacrifice are not empty gestures swallowed by oblivion; they carry eternal weight. On naturalism, whether a person lives like Stalin or like a saint makes no ultimate difference. Both end up equally gone, with no final accounting and no cosmic justice. Therefore, if God does not exist, the objective reality of moral values and duties collapses into subjectivity or mere evolutionary conditioning.
(P2) Objective moral values and duties do exist. (1) We apprehend objective moral values and duties in our experience. - The Holocaust was objectively wrong, not merely culturally unacceptable to mid-twentieth century Europeans. - Torturing children for fun is truly evil, not merely unappealing to most people's preferences. - Rape is objectively wrong, not just socially disadvantageous in most cultures. - Love, generosity, and self-sacrifice are genuinely good, not just behaviors we happen to approve. - When we witness injustice, we do not think "that violates my personal preferences." We think "that is wrong, period." That response has the structure of a truth-claim, not a taste-report. (2) Even those who deny objective morality act as though it exists. - People who claim morality is subjective still get angry when treated unfairly, still praise heroes and condemn villains, and still make moral demands on others as though those demands have real force. - Richard Dawkins claims that morality is merely evolutionary conditioning with no objective foundation, yet throughout his books he condemns religion as evil, praises science as good, and insists we ought to believe what is true. He even offers his own ten commandments for moral living, apparently unaware of the tension with his stated ethical subjectivism. - Philosopher of science Michael Ruse, though an atheist who denies that our moral intuitions track objective truth, admits the intuitions themselves feel inescapable: "The man who says that it is morally acceptable to rape little children is just as mistaken as the man who says 2+2=5" (Darwinism Defended, Addison-Wesley, 1982, p. 275). Nobody truly believes morality is mere personal preference. Our deepest moral convictions resist this reduction. (3) Moral realism is epistemically on par with physical and mathematical realism. - The objection that we cannot trust our moral intuitions because they might be illusions applies equally to our sensory experience and our rational intuitions. If we are not skeptical of our perception of a physical world in the absence of strong defeaters, we should not be skeptical of our moral perception in the absence of strong defeaters either. - We have direct awareness of a physical world through sense perception. We have direct awareness of a moral realm through moral experience and reflection. The reliability of both is defeasible in principle, but neither is defeated by the mere possibility of error. (4) Denying objective morality requires believing things more counterintuitive than objective morality itself. - Moral nihilism requires accepting that there is nothing really wrong with the Nazi Holocaust, that torturing children for fun is not objectively evil, that rape and genocide are not really wrong, and that love, compassion, and self-sacrifice are not really good. - This is so radically at odds with our deepest and most secure moral convictions that any philosophical argument reaching this conclusion must have a false premise somewhere. Our confidence that the Holocaust was genuinely evil is stronger than our confidence in any philosophical premise we might use to argue otherwise. (5) Moral disagreement does not undermine moral objectivity. - Disagreement exists in every objective domain. Scientists disagree about string theory, dark matter, and the interpretation of quantum mechanics. Historians disagree about the causes of World War I. Mathematicians disagreed for centuries about whether actual infinities exist. We do not conclude from this that there are no objective truths in science, history, or mathematics. - The full treatment of moral disagreement, including the distinction between disagreement about moral facts and disagreement about their application, is addressed in Defeater 10. The argument for objectivity from the phenomenon of moral progress is developed in Defeater 11. Therefore, it is far more reasonable to affirm that objective moral values and duties exist than to deny it.
(C) Therefore, God exists. The conclusion follows from P1 and P2 by modus tollens, one of the most reliable forms of deductive inference. P1 establishes the conditional: if God does not exist, objective moral values and duties do not exist. P2 establishes the affirmation of the consequent's negation: objective moral values and duties do exist. The conclusion follows necessarily: therefore God exists. It is worth pausing to identify what kind of being this argument establishes, and how it connects to the broader cumulative case. (1) The moral argument establishes a personal, necessarily good moral lawgiver. - The being established by this argument is not merely a powerful force or an abstract principle. It is a personal being whose nature constitutes the standard of all goodness and whose authoritative commands generate genuine moral obligations. - The being must be personal, because genuine moral duties are owed to someone and issued by someone, and only a personal being stands in the right relationship to moral creatures to generate real obligation. - The being must be essentially and necessarily good. If God's goodness were contingent, moral values would fluctuate. If it were possible for God to be otherwise than good, the moral standard would be unstable. Classical theism holds that God is not merely good but goodness itself, meaning His goodness is identical with His nature rather than a property He happens to have. - The being must be the creator of moral creatures, since the authority that grounds moral obligation is the authority of one who stands in a relationship of creator and sustainer to those obligated. (2) The moral argument connects to and reinforces the other arguments on this site. - The cosmological arguments (First Way through Third Way, and the Leibniz Contingency Argument) establish a necessary being that is the ultimate ground of all contingent reality. The moral argument adds that this same necessary being is the source and standard of all moral value. - The modal ontological argument establishes that if a maximally great being is possible, it necessarily exists. Maximal greatness includes moral perfection. The moral argument provides independent grounds for thinking that a being of maximal moral perfection exists and is the actual ground of objective moral facts. - Each argument contributes a distinct piece: the cosmological arguments establish that a necessary, immaterial, eternal being exists; the ontological argument establishes its maximal greatness; the teleological arguments establish its intelligence; and the moral argument establishes that this same being is the personal, authoritative source of all goodness and obligation. Together they converge on the God of classical theism.
William Lane Craig, Reasonable Faith: Christian Truth and Apologetics, 3rd ed. Wheaton, IL: Crossway, 2008.
Mark Linville, "The Moral Argument," in William Lane Craig and J.P. Moreland, eds., The Blackwell Companion to Natural Theology. Oxford: Wiley-Blackwell, 2009.
Robert Adams, Finite and Infinite Goods: A Framework for Ethics. New York: Oxford University Press, 1999.
William Alston, "What Euthyphro Should Have Said," in William Lane Craig, ed., Philosophy of Religion: A Reader and Guide. New Brunswick, NJ: Rutgers University Press, 2002.
C.S. Lewis, Mere Christianity. New York: HarperOne, 2001.
C.S. Lewis, The Abolition of Man. Oxford: Oxford University Press, 1943.
Paul Copan, "God, Naturalism, and the Foundations of Morality," in Robert Stewart, ed., The Future of Atheism: Alister McGrath and Daniel Dennett in Dialogue. Minneapolis: Fortress Press, 2008.
John Hare, "Is Moral Goodness without Belief in God Rationally Stable?" in Nathan King and Robert Garcia, eds., Is Goodness without God Good Enough? Lanham, MD: Rowman and Littlefield, 2008.
Richard Taylor, Ethics, Faith, and Reason. Englewood Cliffs, NJ: Prentice-Hall, 1985.
J.L. Mackie, Ethics: Inventing Right and Wrong. London: Penguin, 1977.
Erik Wielenberg, Robust Ethics: The Metaphysics and Epistemology of Godless Normative Realism. Oxford: Oxford University Press, 2014.
Sharon Street, "A Darwinian Dilemma for Realist Theories of Value," Philosophical Studies 127, no. 1 (2006): 109–166.
Michael Ruse, Darwinism Defended. London: Addison-Wesley, 1982.
Michael Ruse and E.O. Wilson, "The Evolution of Ethics," New Scientist 108, no. 1478 (1985): 50–52.
Sam Harris, The Moral Landscape: How Science Can Determine Human Values. New York: Free Press, 2010.
Terence Cuneo, The Normative Web: An Argument for Moral Realism. Oxford: Oxford University Press, 2007.
David Brink, Moral Realism and the Foundations of Ethics. Cambridge: Cambridge University Press, 1989.
Richard Boyd, "How to Be a Moral Realist," in Geoffrey Sayre-McCord, ed., Essays on Moral Realism. Ithaca: Cornell University Press, 1988.
G.E. Moore, Principia Ethica. Cambridge: Cambridge University Press, 1903.
Immanuel Kant, Groundwork for the Metaphysics of Morals (1785), trans. Mary Gregor. Cambridge: Cambridge University Press, 1997.
Immanuel Kant, Critique of Practical Reason (1788), trans. Mary Gregor. Cambridge: Cambridge University Press, 1996.
William Lane Craig and Walter Sinnott-Armstrong, God? A Debate between a Christian and an Atheist. Oxford: Oxford University Press, 2004.
People who do not believe in God can still be good, kind, and moral. Atheists and agnostics can recognize moral truths and live admirably moral lives. So God is not needed for morality.
1. The objection addresses a question the argument is not asking.
Three distinct questions must be carefully separated. The first is whether a person must believe in God to live a morally good life. The answer is clearly no: atheists and theists alike can live decent, admirable lives. The second is whether a person can recognize objective moral values without believing in God. The answer is again yes: a person need not believe in God to recognize that loving one's children is good or that rape is wrong. The third question is whether, if God does not exist, objective moral values and duties exist at all. This is the question the moral argument addresses, and the answer is no.
The objection conflates the first or second question with the third. It is therefore a response to an argument no one is making.
2. Moral epistemology and moral ontology are different questions.
How we come to know moral truths is a question of moral epistemology. What grounds the existence and objective truth of moral principles is a question of moral ontology. The moral argument is about ontology, not epistemology. The fact that an atheist can know that gratuitous cruelty is wrong tells us something about how moral knowledge works. It tells us nothing about what makes that moral fact objectively real in the first place.
Think of it this way: you do not need to believe in the Big Bang to observe that the universe exists. But the universe's existence still requires an explanation. Similarly, you do not need to believe in God to recognize moral truths. But morality's objective existence still requires a foundation, and that foundation is what the argument is asking about.
3. Christian theology actually predicts that atheists can be moral.
Scripture teaches that God has written the moral law on the hearts of all people (Romans 2:14-15), so that even those who do not know His name do by nature what the law requires and their conscience bears witness. On the Christian view, everyone has access to moral knowledge because God endowed human beings with moral intuition. Atheists can recognize moral truths and act morally precisely because they were created in the image of a moral God. This is exactly what theism predicts, and it is not evidence against theism.
4. The objection actually presupposes what the argument claims.
When someone says "atheists can be good without God," they are implicitly affirming that there is such a thing as being genuinely good, and that morality is objective enough that both atheists and theists can recognize it. But that is precisely what the moral argument claims: objective moral reality exists. The question is which worldview, theism or naturalism, better explains that reality. The objection assumes the conclusion it is meant to refute.
5. The real question remains entirely unanswered.
The objection does not engage the argument's actual claim. If God does not exist, what grounds the objective moral values and duties that both theists and atheists recognize? Why should creatures who are, on naturalism, rearranged stardust shaped by blind evolutionary processes have genuine moral obligations? The objection offers no answer to this question.
The Euthyphro Dilemma: Is something good because God wills it, or does God will something because it is good? If things are good just because God wills them, then morality is arbitrary and God could have made cruelty good. But if God wills things because they are already good, then goodness is independent of God. Either way, God is not the foundation of morality.
1. The dilemma presents a false choice.
Plato's Euthyphro dilemma, as it applies to theistic ethics, offers exactly two options: either something is good because God wills it (voluntarism), or God wills something because it is already good independently of Him (the independence horn). Both options appear problematic for the theist. But there is a third option that Plato himself did not consider and that has been the standard Christian response since Augustine: God wills something because He is good. This escapes both horns entirely.
2. Moral values are grounded in God's nature, not in His arbitrary will.
On the Divine Nature Theory, God's nature is the ultimate standard of goodness. God is essentially and necessarily loving, just, kind, generous, impartial, and faithful. These are not arbitrary properties God happens to have; they belong to His very essence and cannot be otherwise. He does not consult some external standard of goodness and conform to it (which would make goodness independent of Him). He does not simply decide by fiat what counts as good (which would make morality arbitrary). Instead, His nature simply is the Good. Goodness is defined by reference to God rather than being something beyond Him that He must measure up to.
Think of how the standard pitch A440 works in music. A440 is not a note that happens to be in tune with some external standard of correct pitch. It is the definition of that pitch. Other instruments are in tune insofar as they match it. Similarly, God's nature is not good because it matches some external standard of goodness. God's nature is the standard of goodness. All other good things are good insofar as they reflect it.
3. Moral duties are grounded in God's commands, which flow necessarily from His nature.
While moral values are grounded in God's nature, moral duties are grounded in God's commands. These commands reflect His nature necessarily, so they are not arbitrary. God cannot command cruelty because cruelty contradicts His essentially loving nature. His commands are not decrees issued by fiat; they are expressions of who He is. This means morality is not independent of God (it flows from His very being) and is not arbitrary (it is constrained by His unchanging nature).
4. The dilemma attacks a view that classical theists do not hold.
The first horn of the dilemma (morality is arbitrary because God could have commanded anything) targets a view called pure voluntarism or divine command theory in its crudest form. Classical theism, from Augustine through Anselm and Aquinas to contemporary philosophers like Robert Adams and William Alston, has never held this view. The standard Christian position has always been that God's commands are constrained by and flow from His nature. The dilemma therefore strikes a position that is not on the table.
5. Counterfactuals with impossible antecedents do not create genuine problems.
Critics sometimes ask: what if God commanded cruelty? Would cruelty then be good? But this counterfactual has an impossible antecedent. God is essentially loving; He cannot command cruelty any more than He can cease to exist. Asking what God would do if He were not essentially good is like asking what a triangle would be like if it did not have three sides. The question has no meaningful answer because the antecedent describes an impossibility.
6. The independence horn is not available to the naturalist either.
If someone accepts the independence horn, meaning that goodness exists as a standard independent of God, they face all the problems of atheistic moral realism: how do abstract, impersonal moral facts generate genuine obligations on concrete persons? How did we come to perceive them reliably? What explains their existence? These questions are harder to answer on naturalism than on theism. The full treatment of this challenge is in Defeater 6.
7. The theistic framework is historically well-developed.
This response to Euthyphro is not a modern invention constructed to avoid a problem. Augustine grounded morality in God's unchanging nature. Anselm identified God with the supreme Good. Aquinas developed natural law theory based on God's eternal law as a reflection of His nature. Contemporary philosophers have provided rigorous analytical defenses of this framework. The dilemma may be ancient, but so is the Christian answer, and it remains compelling today.
Immanuel Kant argued that genuine morality requires autonomy: the moral agent must give the moral law to themselves through reason rather than receiving it from an external authority. If morality is grounded in God's commands, moral action becomes mere obedience to a superior, which is heteronomy rather than genuine morality. Divine command ethics therefore undermines the very autonomy that makes moral action possible.
1. Kant's objection, stated precisely.
In the Groundwork for the Metaphysics of Morals (1785), Kant distinguishes two sources of moral law: autonomy, where the rational agent gives the law to themselves through pure practical reason, and heteronomy, where the law is received from an external source, whether another person, society, or God. Kant insists that only autonomous moral action has genuine moral worth. An action done merely from obedience to God's command, without the agent's own rational recognition of its rightness, is prudential compliance rather than genuine morality. On this account, grounding morality in divine command actually corrupts it.
2. The objection targets a crude divine command theory, not the Divine Nature Theory defended here.
Kant's autonomy objection has genuine force against a position that treats God's commands as arbitrary decrees that the moral agent must simply obey without rational understanding. But the Divine Nature Theory is not that position. On the view developed in Defeater 1, God's commands are not external impositions disconnected from rational moral truth. They reflect God's essentially good nature, which is also the standard of goodness that human moral reason apprehends. Recognizing the force of God's commands is not blind obedience; it is the rational recognition of genuine moral truth rooted in the nature of ultimate reality.
3. Kant himself offered a moral argument for God's existence.
A significant irony in this objection is that Kant, its author, was not an atheist. In the Critique of Practical Reason (1788), Kant argued that belief in God is a postulate of practical reason: practical reason itself demands a God who can guarantee the ultimate correspondence of virtue and happiness, which morality requires but the physical world cannot ensure on its own. Kant did not think his autonomy criterion eliminated God from morality. He thought it reconceived the relationship: God is not a moral legislator whose arbitrary decrees replace moral reasoning, but the ground who makes the moral order coherent. The Kantian tradition and the moral argument for God's existence are more compatible than the objection assumes.
4. On theism, moral autonomy and divine grounding are compatible.
God designed human beings as rational moral agents with the capacity to recognize and respond to moral truth through reason and conscience. On the Christian account, the moral law written on the hearts of all people (Romans 2:14-15) is precisely the rational moral structure that Kant describes as apprehensible through practical reason. The theist can affirm both that moral agents genuinely recognize moral truths through their rational nature and that this rational moral nature was given to them by a God in whose image they are made.
The compatibility becomes clear when we consider that Kant's autonomous moral agent, reasoning according to the categorical imperative, will typically arrive at the same moral conclusions that the Divine Nature Theory grounds in God's nature. The convergence is not coincidental: on theism, human rational moral faculties were designed to track a moral reality grounded in God's nature. Autonomy and divine grounding are not rivals. The former is the epistemological mechanism; the latter is the metaphysical foundation.
5. Heteronomy applied consistently eliminates all grounding for morality.
If receiving the moral law from any external source constitutes heteronomy and therefore undermines genuine moral action, then receiving moral beliefs from one's culture, one's evolutionary heritage, one's parents, or one's own desires are equally problematic. No source of moral input would be acceptable except the deliverances of pure practical reason in complete isolation. But Kant's pure practical reason is itself a faculty with a particular character and history. It is not obvious that exercising reason constitutes genuine autonomy while recognizing a divine moral order constitutes heteronomy. The distinction requires more philosophical justification than the objection provides.
Our moral beliefs and behaviors can be fully explained by evolution and social conditioning. Natural selection favored cooperative and altruistic behaviors because they helped our ancestors survive. We do not need God to explain where our morality comes from.
1. Explaining the origin of a belief says nothing about whether the belief is true.
This fundamental distinction, addressed in full in Defeater 0, applies here as well. Evolution may explain how moral beliefs arose, but that is a question of moral epistemology, how we came to hold these beliefs. It is not a question of moral ontology, whether objective moral truths actually exist and what makes them real. The evolutionary account addresses the psychology of moral belief. It leaves entirely untouched the metaphysical question of what makes morality objectively binding.
2. Evolution selects for fitness, not for moral truth.
Natural selection favors beliefs and behaviors that enhance survival and reproduction, not beliefs that are true unless truth-tracking happens to be survival-enhancing. This is the critical problem. On naturalistic evolution, moral intuitions are outputs of a process that is indifferent to whether those intuitions track any objective moral reality. They are adaptive outputs, not perceptions of mind-independent moral facts.
As Ruse and Wilson stated in 1985, ethics on this account is biologically adaptive and ultimately illusory: morality aids survival and reproduction, and any sense that it refers to something genuinely objective beyond the organism has no foundation. The evolutionary account therefore does not just fail to establish objective morality; it actively undermines our confidence that moral beliefs track moral truth at all.
3. The evolutionary debunking argument is self-defeating.
Some use evolution to debunk moral realism: our moral beliefs evolved for survival rather than truth, so we should not trust them to track objective moral facts. But this argument proves far too much. Every human belief, including beliefs about science, mathematics, logic, and the validity of evolutionary theory itself, was formed by the same evolved cognitive faculties. If evolutionary origin undermines the reliability of moral beliefs, it equally undermines the reliability of every other belief those faculties produce, including the belief in evolutionary theory. The debunking argument saws off the branch it is sitting on. For the most rigorous version of this problem, see Defeater 4, which addresses Sharon Street's Darwinian Dilemma.
4. Evolution cannot explain the normative force of genuine moral obligation.
Even if evolution fully explains why we feel certain behaviors are right or wrong, it cannot explain why we genuinely ought to behave in certain ways. It explains a feeling; it does not ground a real obligation. On naturalism, the feeling that I ought not harm my children is a product of evolutionary conditioning. But is there a real moral obligation not to harm them, or is there only the feeling? We all recognize the difference. The genuine obligation is not explained by the evolutionary feeling; it requires a grounding the evolutionary story cannot provide.
5. Some moral convictions resist evolutionary explanation entirely.
Many of our deepest moral commitments are difficult or impossible to explain on purely evolutionary grounds: genuine concern for distant strangers or future generations with whom we share no genetic relationship; willingness to sacrifice personal survival for abstract principles of justice; belief in universal human rights regardless of tribal affiliation, which cuts directly against the in-group favoritism that evolutionary accounts predict. These convictions suggest that moral awareness transcends mere evolutionary conditioning and points toward moral truths we discover rather than adaptive responses we merely have.
6. The theistic view can accommodate evolutionary mechanisms without tension.
The theist has no problem affirming that God worked through evolutionary processes to produce human beings. On this view, God designed those processes to produce creatures with moral intuition, and our moral intuitions, though imperfect due to human finitude and moral failure, generally track objective moral truths because God designed them to do so. Evolution explains the mechanism of how moral awareness developed in human beings. God explains why that mechanism produces intuitions that track real moral truth rather than merely producing adaptive responses to fitness pressures.
Philosopher Sharon Street argues that natural selection shaped our evaluative attitudes to track reproductive fitness, not mind-independent moral truths. If moral realism is true and evolution is unguided, our moral beliefs are mostly unreliable, tracking survival rather than genuine goodness. But if our moral beliefs reliably guide us to objective moral truth, that seems to require some kind of guidance in the evolutionary process. This Darwinian Dilemma appears to trap the moral realist.
1. Street's dilemma stated carefully.
In "A Darwinian Dilemma for Realist Theories of Value" (Philosophical Studies, 2006), Street argues that the moral realist faces an uncomfortable forced choice. Natural selection shaped our evaluative attitudes. If those attitudes have no particular connection to mind-independent moral truths, we have strong reason to think they are mostly false or unreliable, since evolution tracks fitness rather than goodness. But if there is a genuine connection between our evolved attitudes and mind-independent moral truths, the realist owes a convincing explanation of how that connection was established. The atheistic moral realist has no satisfying account of either horn.
2. The dilemma targets the specific combination of unguided evolution and moral realism.
Street's dilemma has maximum force against a particular pairing: unguided evolutionary processes combined with the view that mind-independent moral truths exist. If evolution is genuinely purposeless, there is no mechanism to ensure that the moral attitudes it produces correspond to an independently existing moral order. The atheist who wants to maintain objective moral realism must explain this correspondence without any intelligence behind the process. This is the combination that is philosophically unstable.
3. Theism dissolves the dilemma entirely.
For the theist, neither horn presents any difficulty. If God designed the evolutionary process with the intention of producing creatures with genuine moral perception, then the correspondence between our evolved moral faculties and objective moral truth is exactly what we would expect. God is the bridge between the two. The connection is not a mysterious coincidence; it is the designed outcome of a rational creator who intended to produce moral beings.
This is precisely how we trust our perceptual faculties. We do so partly because we have reason to think our perceptual systems were calibrated to track the world accurately. The theist has the same account of moral perception: God designed us as moral perceivers whose faculties, though fallible and distorted by moral failure, are generally aimed at moral truth.
4. Street's own resolution collapses into relativism.
Street accepts the first horn and concludes that we should abandon mind-independent moral realism in favor of a constructivist view: moral values are constructed relative to our evolved evaluative attitudes. But this collapses into sophisticated subjectivism. If moral values are constructed from our contingent evolved attitudes, then had evolution taken a different path and produced creatures who found cruelty satisfying, cruelty would be good relative to their attitudes. This is not moral objectivity; it is relativism in formal dress. Street's solution to the dilemma gives up the very moral realism it claims to explain.
5. Street's dilemma strengthens the overall case for theism.
Considered as a piece of the overall argument, Street's contribution is significant: she demonstrates with precision that combining unguided evolution with moral realism is philosophically unstable. The naturalist must choose: abandon moral realism, as Street does, or explain the reliability of moral faculties without God. The theist alone can hold both moral realism and an evolutionary account of moral development together without contradiction, because on theism the two were designed to cohere from the beginning.
J.L. Mackie argued in Ethics: Inventing Right and Wrong (1977) that although moral language makes claims about objective moral facts, no such facts exist. Every ordinary moral judgment is therefore false. On Mackie's error theory, objective morality is a systematic and widespread illusion rather than a reality we discover.
1. Mackie's error theory, stated precisely.
Mackie accepted that ordinary moral claims purport to be objectively true. When someone says "torture is wrong," they genuinely mean it is wrong independently of what anyone thinks. Mackie's distinctive move was to agree that this is what moral language claims and then to deny that the world contains anything to make such claims true. All first-order moral judgments, every claim that something is good, bad, right, or wrong, are therefore false. Morality is a widespread error so deep it is built into ordinary moral thought itself.
2. Mackie's argument from queerness actually supports theism.
Mackie's primary motivation for error theory was his argument from queerness: objective moral properties would be entirely unlike anything in a naturalist ontology. They would be non-physical and non-empirical, yet would somehow possess intrinsic prescriptive force, a kind of built-in demand to be followed that nothing purely physical has. Nothing in the naturalist's universe resembles such entities.
The theist's response is to agree entirely with this diagnosis. Objective moral properties do not fit naturalism. They are genuinely strange relative to a purely physical universe. But rather than concluding that they do not exist, the theist concludes that naturalism is inadequate. The existence of genuinely prescriptive moral properties is evidence that reality contains more than matter and energy: specifically, a personal God in whose nature goodness is grounded and whose authoritative commands generate the prescriptive force that Mackie finds so puzzling. The full treatment of this queerness argument as it applies to atheistic moral realism is in Defeater 6.
3. Error theory pays an extraordinary philosophical price.
Accepting error theory requires holding that the following claims are literally false: the Holocaust was wrong; torturing children for fun is evil; rape is morally wrong. Not merely that these things are unpleasant or socially disapproved, but that there is no fact of the matter about their wrongness. This conclusion is so radically at odds with our deepest and most secure moral convictions that most philosophers, including many atheists, find it unacceptable.
As P2 of the moral argument argues, our confidence that the Holocaust was genuinely evil is stronger than our confidence in any philosophical premise that could be used to argue otherwise. When a theory requires abandoning moral convictions of this certainty, that is powerful evidence the theory has gone wrong somewhere.
4. Error theory is self-undermining.
If all normative claims are false or empty, then the claim that we ought to believe error theory is itself a normative claim and therefore false or empty. The same applies to epistemic norms such as "you should follow the evidence" or "rationality requires updating beliefs on good arguments." Error theory, applied consistently, undermines the very norms of reasoning that any argument for it presupposes. The theory cannot coherently recommend itself.
5. The near-universal experience of moral obligation requires explanation.
Mackie acknowledges that humans universally experience moral claims as objectively binding. He explains this through evolutionary psychology. But as Defeater 3 establishes, evolutionary explanation of why we hold moral beliefs says nothing about whether those beliefs track moral truth. On theism, the near-universal human experience of genuine moral obligation is exactly what we would predict: God created us as moral beings with faculties designed to perceive genuine moral reality, however imperfectly.
Maybe objective moral truths exist as fundamental features of reality without God, like mathematical truths or logical laws. Moral facts can simply be brute necessary features of the universe, requiring no further grounding. We can have objective morality on atheism through moral realism without any divine foundation.
1. The queerness problem: moral obligations cannot be impersonal abstract objects.
Even if we grant that abstract moral facts exist as necessary features of reality alongside mathematical truths, they face a decisive problem: abstract objects are causally inert. Numbers do not do anything. The proposition "7 is prime" does not impose requirements on anyone. Yet moral obligations are not merely true abstract claims. They are prescriptive: they bind the will of concrete persons and demand action regardless of personal preference.
Richard Taylor identifies the problem precisely in Ethics, Faith, and Reason (1985): a duty is something owed to someone. Obligations have a personal structure. Political obligations are intelligible because there is a state that issues and enforces them. Moral obligations, on theism, are intelligible because they are issued by a Creator to whom they are owed. But abstract moral facts, hovering in conceptual space with no one who decreed them and no one to whom they are owed, cannot generate genuine obligations in the same way. It is like saying the number 7 requires you not to steal. Numbers do not issue requirements. Neither do impersonal abstract moral truths.
2. Atheistic moral realism faces the cosmic coincidence problem.
Suppose moral values exist as abstract entities independent of God, and humans evolved through blind natural processes. It would then be a remarkable and unexplained coincidence that creatures evolved on Earth who can recognize independently existing abstract values, and whose moral intuitions largely align with the independently existing moral realm. There is no explanation for why evolution would produce faculties that track abstract, mind-independent moral facts when such tracking has no obvious survival value.
On theism, this coincidence disappears. One mind created both the moral order and the moral creatures designed to perceive it. The fit between moral faculties and moral reality is the designed outcome of a rational creator, not a lucky accident.
3. Wielenberg's supervenience proposal and why it falls short.
Erik Wielenberg's Robust Ethics (Oxford, 2014) offers the most sophisticated contemporary defense of atheistic moral realism. Wielenberg argues that moral facts supervene on natural facts: given certain natural conditions (such as a being capable of suffering), certain moral facts simply hold (such as that causing gratuitous suffering is wrong). These are necessary connections requiring no further grounding.
Wielenberg anticipates the objection that he is merely asserting brute unexplained moral facts, and he responds that the theist faces a parallel problem: why is God's nature good? He argues that "God's nature just is the Good" is no better explained than "these moral facts just hold."
This symmetry objection fails on close examination. The theist's terminus is a personal necessary being whose nature is constitutively what goodness means, and who stands in the right relationship to created persons to generate genuine moral obligations. Grounding morality in a person with a nature, a will, and a relationship to us explains both moral values (rooted in God's nature) and the normative authority of moral duties (rooted in God's commands). Wielenberg's brute necessary moral facts, by contrast, are impersonal abstract entities with no one behind them, no authority issuing them, and no relationship to the persons they are supposed to obligate. The positions are not parallel. The theistic terminus does explanatory work that the atheistic terminus cannot do, because persons are the right kind of thing to ground obligation and authority in a way that impersonal abstract properties simply are not.
4. Theism provides a far more unified and natural home for objective morality.
On theism, moral values are grounded in God's necessarily good nature, moral duties are grounded in God's authoritative commands flowing from that nature, and moral accountability is grounded in God's justice. This gives a unified explanation for all three dimensions of morality: why it is objectively real, why it is binding, and why it matters ultimately. On atheistic moral realism, the existence of abstract moral facts is a brute unexplained feature of reality, their binding authority on persons remains unexplained, and their ultimate significance in a universe indifferent to moral choices is entirely absent. Theism is not merely one option among equals. It is the framework that makes all the pieces of moral reality fit together naturally.
Philosophers Richard Boyd, David Brink, and Nicholas Sturgeon have developed a sophisticated naturalistic moral realism called Cornell Realism. On this view, moral properties are real features of the world, identified with natural properties through substantive philosophical inquiry rather than mere definition. "Good" picks out whatever natural properties constitute genuine human flourishing, and this identification is discovered empirically rather than stipulated. This provides objective morality without any need for God.
1. Cornell Realism, stated carefully.
Richard Boyd ("How to Be a Moral Realist," in Essays on Moral Realism, Cornell University Press, 1988) and David Brink (Moral Realism and the Foundations of Ethics, Cambridge University Press, 1989) argue that moral properties are real natural properties, but the identification between them is not a simple definitional equation. Rather, moral terms like "good" refer to whatever natural properties constitute genuine human flourishing. This is a substantive identification that must be discovered through philosophical and empirical inquiry, not stipulated in advance. The realism is genuine because the natural properties are real, and the identification is non-trivial because it is discovered rather than defined.
2. G.E. Moore's open question argument shows that moral properties resist naturalistic identification.
G.E. Moore argued in Principia Ethica (1903) that any attempt to identify moral properties with natural properties faces a decisive objection: even if we know all the natural facts about a situation, the question "but is it good?" remains genuinely open and non-trivial. If "good" simply meant "conducive to flourishing," the question "is what is conducive to flourishing good?" would be as trivially closed as "is a bachelor unmarried?" Yet it does not feel closed. It remains a substantive question.
This openness suggests that the property goodness is not identical to any natural property, no matter how complexly described. Cornell Realism must either deny that the open question has the significance Moore claims, or accept that moral properties are not straightforwardly identical to natural ones.
3. Even successful naturalization would not explain moral obligation.
Suppose we grant for the sake of argument that Cornell Realism successfully identifies moral properties with natural properties. This would establish that certain natural states of affairs are good. It would not explain why any person has a genuine obligation to pursue those states of affairs. The is-ought gap, first clearly articulated by Hume, remains: knowing all the natural facts, including that something constitutes human flourishing, does not by itself tell us that we are obligated to pursue it.
On theism, this gap is bridged by God's authoritative commands. God commands what promotes genuine flourishing because that is what His essentially good nature requires, and His commands generate genuine obligations in His creatures. On Cornell Realism, there is no commander, no authority, and therefore no genuine obligation. Naturalized moral facts describe the world; they do not bind the will.
4. The reliability of our moral faculties remains unexplained on Cornell Realism.
Brink acknowledges that defending Cornell Realism requires explaining how we came to perceive moral properties reliably. The explanation typically appeals to some form of natural selection: perhaps tracking moral properties was fitness-enhancing, so evolution produced faculties that generally track them. But as Defeater 4 (Street's Darwinian Dilemma) establishes, this appeal to evolution faces a dilemma: unguided evolution selects for fitness, not for tracking mind-independent moral truths. The Cornell Realist who wants to explain moral reliability through evolution inherits all of Street's problem.
5. Cornell Realism does not escape the cosmic coincidence problem.
Even if moral properties are identical to certain natural properties, on atheism there is no explanation for why the universe has the character that makes those natural properties correspond to genuine moral goodness. Why should the features that constitute human flourishing be the ones that matter morally? Why should the universe be the kind of place where natural flourishing aligns with moral worth? On theism, this alignment is exactly what we would expect: God created both the moral order and the natural world, and designed human flourishing to correspond to what is genuinely good. On Cornell Realism operating within atheism, the alignment is another unexplained coincidence.
Sam Harris argues in The Moral Landscape (2010) that objective morality can be grounded in the science of well-being without any reference to God. Once we define good as that which promotes the flourishing of conscious creatures, morality becomes a purely empirical question answerable by neuroscience and psychology. Science can determine human values.
1. Harris's view still leaves the is-ought gap entirely unbridged.
Science can tell us what actions tend to promote well-being and reduce suffering. But no amount of empirical data can tell us why we genuinely ought to promote well-being rather than ignore it. The gap between descriptive facts and normative obligations is precisely what any account of moral foundations must bridge. Harris does not bridge it; he simply assumes that promoting the well-being of conscious creatures is what "good" means, and then treats the normative question as already settled by definition.
Think of a skilled mechanic who can describe exactly how an engine works. That knowledge tells us what will happen if we press the accelerator. It does not tell us whether we ought to drive carefully or recklessly. Scientific description of mechanisms does not generate prescriptive obligation.
2. "Flourishing" is not a morally neutral concept that science can define.
Defining what counts as flourishing already requires substantive moral judgments that Harris's science cannot itself supply. Different philosophical and cultural traditions have radically different understandings of what a flourishing human life consists in: one emphasizes pleasure and the absence of pain; another emphasizes virtue and moral excellence; another emphasizes relationship and love; another emphasizes creative achievement. Harris quietly imports a particular conception of flourishing, shaped by broadly utilitarian assumptions, without acknowledging that this selection is itself a prior moral choice that his scientific method cannot justify.
3. The view collapses into the very subjectivism Harris wants to avoid.
If well-being is ultimately determined by the brain states or preferences of conscious creatures, morality becomes relative to those preferences. If evolution had produced creatures whose form of flourishing consisted in domination and cruelty, cruelty would count as good on Harris's view because it would constitute flourishing for such creatures. This is not objective morality. It is sophisticated subjectivism dressed in neuroscientific language.
4. Theism explains why flourishing matters morally, which Harris cannot.
On theism, human flourishing matters because humans are created in the image of God with inherent dignity and worth rooted in their relationship to their Creator. Promoting well-being is not an arbitrary preference shaped by evolution; it is alignment with the objective good grounded in God's loving nature. The theistic framework provides both the descriptive account of what flourishing involves and the normative explanation for why we are obligated to pursue it.
5. The moral argument remains untouched by Harris's proposal.
Harris offers a helpful scientific description of what behaviors tend to promote human well-being. He does not explain why any person has a real, binding moral obligation to pursue that well-being rather than to pursue their own narrower interests instead. That genuine normative force still requires the personal, authoritative grounding that the moral argument identifies in God.
Moral facts are no queerer than epistemic norms, mathematical truths, or logical laws. We accept those abstract, mind-independent facts on atheism without invoking God. If naturalism can accommodate those normative realities, it can accommodate moral facts by the same reasoning. This companions-in-guilt objection suggests moral facts are not specially problematic.
1. The companions-in-guilt argument, stated precisely.
Terence Cuneo argues in The Normative Web (2007) that moral facts are in the same position as epistemic facts: facts about what we ought to believe given the evidence, what constitutes a valid inference, and what reasoning requires. If we accept epistemic normativity on atheism without invoking God, we should accept moral normativity on the same terms. The two domains are companions: if moral facts are guilty of being metaphysically queer, epistemic facts are equally guilty. Since we do not abandon epistemic realism, we should not abandon moral realism either.
2. The argument identifies a genuine structural parallel but misses a crucial disanalogy.
Cuneo is right that epistemic and moral norms are structurally similar in being normative and not straightforwardly reducible to physical facts. The parallel has genuine force. However, there is a disanalogy that the argument overlooks: moral obligations have an inescapably personal and relational character that epistemic norms do not have in the same way.
Epistemic norms tell us what we must do if we want to reach truth or reason correctly. They are instrumental in a certain sense: follow these norms if you want to be a rational believer. Moral obligations bind the will regardless of what we want, impose themselves on concrete persons even when compliance is costly, and are owed to other persons or to a moral authority. This personal, relational, and unconditional character of moral obligation is not shared by the epistemic norm that one ought to proportion belief to evidence.
3. Moral facts still require a personal grounding that abstract objects cannot provide.
Even if epistemic and moral facts are equally real, the question is what kind of grounding each requires. Epistemic norms can be understood as constitutive features of rationality itself: what it is to reason at all. Mathematical truths are features of abstract structure. Logical laws are features of what it is for any claim to follow from any other. These are not obviously obligations in the full personal sense.
Moral obligations, by contrast, are owed to persons and issue from moral authority. Only a personal, necessary being can stand in the right relationship to moral creatures to generate genuine moral duties in the way that a state or a person can generate genuine legal or interpersonal duties. Abstract objects, however necessarily existing, cannot fill this role because they cannot issue commands, stand in relationships, or serve as the source of genuine authority over persons.
4. Theism provides the most unified and economical explanation of all normativity.
The theist does not need to treat epistemic, moral, and logical normativity as three separate brute features of reality. On theism, all three flow from the nature of a rational, good, and necessarily existing God who created rational moral beings in His image. Epistemic norms reflect the rational character of a God who is Logos; moral norms reflect the good and authoritative character of a God who is the Good; logical norms reflect the rational consistency of divine thought that grounds the structure of reality. Theism explains all normative domains in terms of one ultimate personal ground. Atheism must treat each normative domain as a separate brute feature of a universe that has no personal ground for any of them.
5. The companions-in-guilt strategy ultimately highlights rather than resolves the problem.
Once we see that moral facts have a distinctly personal, relational, and unconditional character that distinguishes them from other abstract normative facts, the need for a personal foundation becomes clearer rather than less clear. The companions-in-guilt argument, pressed carefully, reinforces the moral argument's conclusion: the only adequate ground for the kind of normative authority that genuine moral obligation requires is a personal, necessary being.
People across cultures and throughout history disagree profoundly about morality. If moral truths were objective, we would expect greater convergence. This widespread disagreement suggests morality is subjective or culturally relative rather than objectively real.
1. Disagreement does not imply subjectivity in any other domain.
Scientists disagree about string theory, dark matter, and the correct interpretation of quantum mechanics. Historians disagree about the causes of World War I and the character of the Roman Empire's decline. Mathematicians disagreed for centuries about whether actual infinities exist. We do not conclude from these disagreements that there are no objective truths in science, history, or mathematics. The mere fact of disagreement, however widespread or persistent, does not establish that there is no fact of the matter.
2. Substantial cross-cultural moral agreement actually exists.
The degree of moral disagreement across cultures is regularly overstated. C.S. Lewis documented in The Abolition of Man that fundamental moral principles appear with remarkable consistency across ancient Egypt, Babylon, China, Greece, and Rome; across Christianity, Judaism, Islam, Hinduism, and Buddhism; and across indigenous cultures from every continent. Every culture condemns the murder of innocent community members, values courage and condemns cowardice, recognizes some principle of justice and fairness, and honors self-sacrifice for the community. The cross-cultural similarities in fundamental moral conviction are far greater than the differences at the applied level.
3. Many apparent moral disagreements are actually disagreements about facts, not values.
When the Aztecs practiced human sacrifice and we condemn it, this need not represent a fundamental disagreement about moral values. If you genuinely believe the gods demand human sacrifice to prevent cosmic catastrophe, then sacrificing one person to save the population may follow from the shared moral principle that lives should be protected when possible. The disagreement is about the factual belief concerning divine demands, not about the underlying moral value of protecting life.
Abortion provides a contemporary example. Most people across this debate share the moral principle that persons should not be killed without just cause. The disagreement is predominantly about the factual or metaphysical question of when personhood begins. Disagreement about the application of a shared principle to a contested factual question is not evidence of moral subjectivity.
4. Disagreement about application is consistent with objectivity of underlying principles.
The principle "be just" is accepted across cultures. But what justice requires in a specific situation involves judgment about the relevant facts, the weights of competing considerations, and the application of the general principle to particular circumstances. Disagreement at the level of application no more undermines the objectivity of the underlying principle than disagreement about a patient's diagnosis undermines the objectivity of medicine.
5. Some apparent moral disagreement reflects moral blindness rather than genuine subjectivity.
Slave owners had powerful financial incentives to believe that slavery was morally acceptable. The Nazis convinced populations through propaganda and ideology to accept atrocities as just. Sexual predators rationalize their behavior to themselves. We do not allow these cases of motivated moral blindness to undermine our confidence in objective moral truth, any more than we allow flat-earth believers to undermine our confidence in objective geography. Moral error caused by self-interest, propaganda, or corruption tells us about human weakness and fallibility, not about the absence of moral truth.
6. Moral disagreement itself presupposes moral objectivity.
When you and I genuinely disagree about whether an action is permissible, we are each claiming that there is a fact of the matter about which one of us is mistaken. Genuine disagreement, as opposed to mere expression of different preferences, presupposes that both parties believe there is something to be right or wrong about. If morality were purely subjective, we would not be disagreeing at all: we would simply be reporting different personal states, as when one person says vanilla ice cream is better and another says chocolate is. The very phenomenon of genuine moral disagreement, with its characteristic features of argument, evidence, reflection, and the expectation that reasoning should persuade, presupposes the objectivity of the domain being disputed.
If God's nature is the unchanging standard of moral truth, how do we explain genuine moral progress throughout history? Societies have moved from accepting slavery to condemning it, from denying women equal rights to recognizing them, from tribal ethics to universal human rights. If the moral standard never changed, does this mean ancient slave-owning societies were simply ignorant of what God's nature requires? And if so, how confident should we be that our current moral understanding is correct?
1. Moral progress is precisely what an objective moral standard predicts.
The very concept of moral progress makes sense only if there is an objective standard that societies can more or less accurately approximate over time. If morality were culturally relative, we could not say that abolishing slavery was progress; we could only say it was a different practice from what came before. The fact that we confidently describe the abolition of slavery, the extension of rights to women, and the recognition of universal human dignity as progress, rather than merely as change, presupposes that there is a real standard those developments were moving toward.
Far from undermining the theistic account, moral progress is one of its strongest confirmations. It shows that moral reality has a character that human societies can track more or less accurately, and that some approximations are better than others, exactly what we would expect if there is an objective moral standard grounded in God's nature.
2. The distinction between the standard and human knowledge of the standard is crucial.
The Divine Nature Theory does not require that human moral knowledge has been complete or accurate at any historical moment. God's nature is the unchanging standard. Human understanding of that standard has developed, deepened, and improved over time, just as scientific knowledge of an unchanging physical reality has developed and improved.
Ancient civilizations knew that murder and theft were wrong. They did not always extend this recognition to persons outside their tribe or social class. Moral progress consists in the extension and refinement of moral knowledge to more accurately reflect the full scope of what God's nature requires. The standard did not change; the human apprehension of the standard became clearer.
3. Moral reformers appealed to an objective standard that transcended prevailing social norms.
The great moral reformers in history, precisely those responsible for what we recognize as moral progress, were not merely reporting that their culture had changed. They were arguing that prevailing practices were wrong by appeal to a higher standard. William Wilberforce did not argue that slavery had become culturally unfashionable. He argued that it was objectively wrong because human beings bear the image of God and cannot be treated as property. Martin Luther King did not argue that segregation was merely unpopular. He argued that it violated the genuine moral dignity that all persons possess by their nature.
These arguments only have force if there is an objective standard to which they appeal. Moral reform is possible precisely because moral reformers can identify a gap between how society currently treats persons and how they genuinely ought to be treated. That gap presupposes an objective moral standard independent of current social practice.
4. The confidence question cuts both ways.
The objection raises a genuine epistemic point: if ancient peoples were mistaken about slavery, we should hold our own moral beliefs with some humility, acknowledging that future generations may recognize errors we cannot currently see. This is a reasonable observation and theism readily accommodates it: human moral knowledge is real but fallible, shaped by finitude and moral failure.
But the objection does not generate symmetry between theism and naturalism. On naturalism, there is no objective standard relative to which our moral beliefs could be more or less accurate. Future moral "progress" would be merely further change, not genuine improvement. On theism, future moral development could represent genuine approximation to the objective standard grounded in God's nature. Only theism makes sense of the aspiration to moral progress as progress toward something real.
5. Moral regress confirms the need for an objective standard.
Not all change in moral practice represents progress. History also contains examples of moral regression: civilizations that developed sophisticated ethics that were later corrupted; societies that moved toward greater brutality; individuals and groups that knew what was right and chose what was wrong. We distinguish moral progress from moral regress, and this distinction requires an objective standard. If morality were relative to cultural change, there would be no difference between progress and regress, only difference. The theistic framework provides the standard that makes the distinction meaningful.
Religious people have committed terrible atrocities throughout history: the Crusades, the Inquisition, religious wars, terrorism. Some religious texts contain troubling moral commands. If God is the foundation of morality, why has religion produced so much evil?
1. The objection addresses human behavior, not the foundation of morality.
The moral argument claims that God is the foundation of objective moral values and duties. It does not claim that all religious people behave morally, that all actions done in God's name are good, or that all religious traditions accurately reflect God's character. Humans misusing or distorting morality does not eliminate the objective standard any more than counterfeit currency eliminates genuine money or false scientific theories eliminate objective physical laws. The failures are failures of human beings to live up to the standard, not evidence that the standard does not exist.
2. Condemning religious atrocities presupposes the objective moral standard the argument defends.
Notice what happens when someone says "the Crusades were evil" or "religious terrorism is wrong." They are appealing to objective moral standards that transcend religious opinion. The claim is not merely that these actions went against the culture's preferences or violated social norms. It is that they were genuinely, objectively wrong regardless of the religious motivations behind them.
But where do these objective standards come from? The objection uses them to critique religious behavior. The moral argument is asking about their source. The theist's answer is God's nature, properly understood. So the objection actually demonstrates the need for exactly what the moral argument provides: an objective moral standard that stands above human religious practice and by which that practice can be judged.
3. Christianity itself provides internal resources to condemn atrocities done in its name.
Jesus condemned religious hypocrites in the strongest terms (Matthew 23). Paul warned against those who distort the gospel (Galatians 1:8-9). The New Testament explicitly commands love of enemies (Matthew 5:44), radical forgiveness, care for the vulnerable, and self-giving service. John writes that God is love (1 John 4:8), and the entire New Testament trajectory is toward expanding the circle of moral concern rather than contracting it.
When Christians historically committed atrocities, they were violating their own stated moral standard. We can judge them by the very standard they claimed to follow. This is only possible because that standard is objective, publicly accessible, and not reducible to whatever religious authorities happen to command at any given moment.
4. Explicitly atheist regimes have also committed massive atrocities.
While this fact does not excuse any religious evil, the historical record does not support the narrative that religion is a uniquely dangerous source of moral failure while irreligion produces moral progress. Some of the largest mass killings in history were carried out by explicitly atheist regimes committed to the elimination of religious belief: Stalin's Soviet Union, Mao Zedong's China during the Great Leap Forward (historian Frank Dikötter estimates approximately 45 million deaths in Mao's Great Famine, 2010), and Pol Pot's Cambodia.
A careful thinker will rightly note that these atrocities were not committed because of atheism in the way that some religious violence has been explicitly religiously motivated. That distinction is fair. The broader point is that human evil is a universal human problem, not a uniquely religious one. Both religious and irreligious actors require an objective moral standard by which their actions can be judged. The moral argument is about what provides that standard.
5. Difficult passages in Scripture require careful interpretation rather than dismissal.
Some cite troubling Old Testament passages, including commands in the context of ancient warfare and regulations of existing social practices, as evidence that divine command theory produces an unreliable moral foundation. Several considerations apply. The literary genre, historical context, and redemptive-historical development of Scripture all require careful attention. Ancient Near Eastern context differs dramatically from modern assumptions, and interpretation requires understanding the literary and historical setting.
More fundamentally, Jesus is the fullest revelation of God's character in classical Christian theology. His teachings of love, mercy, radical forgiveness, and self-sacrifice are the interpretive lens through which the full sweep of Scripture is read. For a fuller treatment of difficult biblical texts and their interpretation, see the discussion of scriptural difficulties elsewhere on this site.
You say God's nature is the standard of goodness. But what makes God's nature good rather than bad? If you cannot answer this without appealing to some standard beyond God, then God is not the ultimate foundation of morality after all. And if you simply declare that God's nature just is the Good, this seems arbitrary.
1. The question misunderstands what it means to be an ultimate standard.
Every explanatory chain must terminate somewhere. An infinite regress of standards explains nothing: if X is good because of standard Y, and Y is good because of standard Z, and so on without end, no genuine explanation is ever provided. And a circular standard, where X is good because of Y and Y is good because of X, provides no real justification at all. Therefore, if objective moral truth exists and has an explanation, there must be some ultimate standard that is not itself good by virtue of conforming to something more fundamental.
When we reach an ultimate standard, the question "but what makes it good?" cannot be answered by appeal to anything more basic, because by definition nothing more basic exists. The question demands an impossibility: an explanation of the most fundamental thing in terms of something beyond it. This is not a weakness of the theistic account; it is a feature of all ultimate explanations. Asking "what makes God's nature good?" is like asking "what caused the first cause?" or "what is north of the North Pole?" The question applies a framework that does not extend to the terminus of all explanation.
2. God's nature does not become good by conforming to an external standard. God's nature simply is the Good.
On the Divine Nature Theory, God's nature does not measure up to some independent standard of goodness that exists alongside Him. God's nature constitutes what goodness means. All other good things are good by virtue of their relationship to and reflection of God's nature. There is no external goodness-meter against which God is evaluated and found passing; God's nature is the meter itself.
Think of how a particular musical note defines a pitch. The standard pitch A440 does not achieve the property of being A440 by measuring up to some external criterion of A-ness. A440 is the definition of that pitch. All other instruments are in tune insofar as they match it. Similarly, God's nature is not good because it matches some external standard. God's nature is the standard. All other goods are good insofar as they reflect it.
3. This is not arbitrary because God exists necessarily and His nature cannot be otherwise.
The most serious version of the objection presses: even if God's nature is the standard, could the standard have been different? Could God have had a different nature, making cruelty the good? This worry conflates contingency with arbitrariness. God exists necessarily, and His nature is essential to Him rather than accidental. God's loving, just, and generous nature is not a contingent fact about God that could have been otherwise. It is part of what God necessarily is. There is therefore no possible scenario in which God's nature is different.
This is why asking "what if God had been evil?" is like asking "what if there were round squares?" The antecedent describes a genuine impossibility, not a merely different scenario. The necessity of God's nature is precisely what makes it a stable and non-arbitrary foundation for moral truth.
4. We recognize God's goodness through moral intuition and revelation, not through circular reasoning.
How do we know that God's nature is genuinely good rather than merely powerful? We apprehend moral truths through the moral faculties God gave us: reflection on paradigm cases of goodness and evil, reasoning about human flourishing and dignity, and the evidence of God's character as revealed in Scripture and supremely in Jesus Christ. When we examine the character of God as revealed there, we find love, justice, mercy, faithfulness, patience, and self-giving sacrifice. These are precisely the properties our moral perception identifies as genuinely and supremely good. Our recognition of God's goodness is not circular. It is the application of moral faculties to the question of what ultimate reality is like, and it converges on a being whose character matches and grounds what our best moral intuition tells us goodness is.
5. Perfect being theology provides the philosophical underpinning.
Anselm's tradition of perfect being theology defines God as the greatest conceivable being, meaning a being who has all perfections to the maximum possible degree and has them essentially rather than contingently. Goodness is a perfection. Therefore, God is necessarily and maximally good, not because He measures up to an external standard but because being the paradigm and source of all goodness is part of what it is to be the greatest conceivable being. This is a principled derivation of God's essential goodness from His nature as the ultimate reality, not a bare stipulation.
6. The alternative faces an even more serious version of the same problem.
If someone posits an independent standard of goodness beyond God, we can ask: what makes that standard good rather than bad? And what makes the thing that makes it good itself good? The regress threatens regardless of whether we start from God or from an independent moral standard. The question is which terminus is more philosophically satisfying. A personal, necessary, maximally great being whose nature constitutes what goodness means is a more satisfying terminus than impersonal, abstract, brute moral facts floating in conceptual space with no one behind them and no explanation for their existence or authority. The theistic terminus does explanatory work that no other candidate can match.
Five Ways
Arguments from Thomas Aquinas (1225-1274)
