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#165 Does Theistic Ethics Derive an “Ought” from an “Is”?

June 14, 2010

Dr. Craig,

Like many others, I would like to begin my question by thanking you for the encouragement your rational defense of the Christian faith and your Christ-like example have been to me through my spiritual journey. You have been an intellectual hero of mine for the past five years. Within that time, I have become familiar with the moral argument for God's existence which you defend. Though I intuitively find this argument plausible, I find myself incapable of answering four questions concerning it.

1. Does a Theistic justification of morality derive an "ought" from an "is?" The theist ultimately grounds moral values in God's unchanging nature. But this seems tantamount to saying that because God is a certain way we ought to behave in certain ways. Is this not deriving an "ought" from an "is?"

2. How should the proponent of the moral argument define "right" and "wrong?" The first premise of the moral argument maintains that if God did not exist, neither would objective moral values exist. Furthermore, you define "objective moral values" as values that are right or wrong irregardless of what anyone else believes. Hence, it seems to me, the truth of the first premise depends on what is meant by "right" and "wrong." Elsewhere, you define "right" and "wrong" in terms of God's commands. But if the proponent of the moral argument defines "right" and "wrong" in this way, the argument becomes question-begging. At the same time, however, the proponent of the moral argument cannot grant a naturalistic definition of "right" and "wrong," say, for example, "what is conducive to survival." For, since there are objective facts as to what is and is not conducive to survival, something that is or is not conducive to survival could be morally right or wrong irregardless of the beliefs of others and so, by your definition, would constitute objective moral values. But such a naturalistic understanding of moral values does not need to appeal to God and thus, if "right" and wrong" were so defined, the first premise of the moral argument would be false. So how should the proponent of the moral argument define "right" and "wrong" so as not to render the argument question-begging while at the same time not allowing naturalistic definitions?

3. Is the moral argument a good piece of natural theology? The second premise of the moral argument is, I think, not only true, but obviously true. Like you, Dr Craig, I think belief in objective moral values is properly basic: we can simply see that some things are really right and wrong. But if the proponent of the moral argument defines "right" and "wrong" in some nonnaturalistic way, then it seems less clear to me that it is these kinds of moral values that we apprehend. As J.L. Mackie observed, nonnaturalistic moral values are strange sorts of entities; and while perhaps a trained philosopher may have such moral values in mind when judging something to be right or wrong, the layperson, it seems to me, most plausibly does not. Hence, it seems that nonnaturalistic moral values are not properly basic. But only if it is these nonnaturalistic moral values which we all recognize in the world is the moral argument a good piece of natural theology. So how do we know that the moral values which we all affirm in the second premise are the same moral values defined in a nonnaturalistic way in the first premise? That is, how do we know we are not really affirming some reductively natural moral values instead?

4. Do objective moral values entail purposeful existence? In thinking about the first premise of the moral argument, I have come up with what seems to me to be a plausible argument in support of it. This argument runs as follows:

1. If God does not exist, then the universe is without purpose.

2. If the universe is without purpose, then objective moral values do not exist.

3. Therefore, if God does not exist, then objective moral values do not exist.

I think most atheists would agree with the first premise; hence, it is the second premise which is crucial to the argument. I must admit, however, that I find this premise plausible solely on intuitive grounds. I just can't see how one can say that the universe is purposeless and then, in the same breath, claim that there are ways we are supposed to be behaving. For, in a universe with no purpose I am not even supposed to be here; I just am, by accident. But if I am not supposed to be here then how is it that there are objective ways in which I am supposed to be behaving? Or more generally, if the human race is not supposed to be here, then how is it that there are objective ways that they are supposed to be behaving? That there are objective ways we are suppose to behave, therefore, seems to presuppose that we are supposed to be here after all; the universe is not purposeless. But if God did not exist, then it would be purposeless. Therefore, objective standards of behavior (i.e. objective moral values) seem to count as evidence for God's existence. Does this sound plausible to you? A critical evaluation of my argument and the intuitions upon which it is based would be greatly appreciated.

I thank you in advance for any help you would be willing to give me on these questions, and thank you for all the help you have already given me throughout the years.


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Dr. craig’s response


It is your first question which I find most interesting, Charles. This question is a matter of concern, not just for natural theologians, but for anyone who holds to an ethical theory which grounds morality in God.

The moral argument as such makes no attempt to explain morality’s grounding in God. It makes only two assertions:

1. If God does not exist, objective moral values and duties do not exist.

2. Objective moral values and duties do exist.

The two premisses imply God’s existence but do not entail a theory of how moral values and duties relate to God. So the theist who defends this argument has a range of options open to him.

The theory that I have defended is a form of Divine Command Theory. According to this view our moral duties are constituted by the commands of an essentially just and loving God. It seems to me that this theory does derive an “ought” from an “is,” and justifiably so—though not in the way you imagine. The theory does, as you say, ground moral values in God's unchanging nature. God is the paradigm of goodness. But that is not to say that “because God is a certain way we ought to behave in certain ways.” No, our moral obligations and prohibitions arise as a result of God’s commands to us. God’s nature serves to establish values—goodness and badness—while God’s commands establish moral duties—what we ought or ought not to do. Grounding moral values in God no more derives an “ought” from an “is” than does Plato’s grounding values in the form of the Good (indeed, one of my critiques of moral platonism is precisely its failure to provide any basis for moral duty). The theist and Plato just have a different ontological ultimate.

So how does Divine Command Theory derive an “ought” from an “is”? Well, it says that we ought to do something because it is commanded by God. That is deriving an “ought” from an “is.” Someone might demand, “Why are we obligated to do something just because it is commanded by God?” The answer to that question comes, I think, by reflecting on the nature of moral duty. Duty arises in response to an imperative from a competent authority. For example, if some random person were to tell me to pull my car over, I would have absolutely no legal obligation to do so. But if a policeman were to issue such a command, I’d have a legal obligation to obey. The difference in the two cases lies in the persons who issued the commands: one is qualified to do so, while the other is not.

Now, similarly, in the case of moral obligations, these arise as a result of imperatives issued by a competent authority. And in virtue of being the Good, God is uniquely qualified to issues such commands as expressions of His nature. What is deficient in Plato’s theory is a person who can issue moral imperatives as an expression of the Good; but that want is supplied by theism. So it seems to me that Divine Command Theory’s derivation of an “ought” from an “is,” far from being objectionable, captures a central feature of moral duty and plausibly grounds it.

Your second question confuses moral semantics with moral ontology. The Divine Command theorist does not define moral values or duties at all; rather he asks for their ontological foundation. We can accept the customary understanding of moral terms like “good, “right,” “wrong,” etc. with equanimity. We’re not making a semantic claim about the meaning of moral terms. Rather we are trying to explain their objective foundation. Similarly, the naturalist is not pressing a semantic claim about the definition of words but is offering a different foundation for values and duties than the theist. The question is, which moral theory is more plausible?

Once that confusion is cleared up, the third question takes care of itself. The proponent of the moral argument is using the relevant terms in the standard way. In his recent doctoral dissertation on the Moral Argument (Ohio State University, 2009) Matthew Jordan lists the following properties, revealed by an examination of our moral experience, which must characterize any adequate theory of moral duty:

Objectivity: The truth of a moral proposition is independent of the beliefs of any particular human being or human community.

Normativity: Moral considerations, as such, constitute reasons for acting.

Categoricity: Moral reasons are reasons for all human persons, regardless of what goals or desires they may have.

Authority: Moral reasons are especially weighty reasons.

Knowability: In normal circumstances, adult human beings have epistemic access to morally salient considerations.

Unity: A human person can have a moral reason to act or to refrain from acting in ways that affect no one other than the agent who performs the act.

Any theory that fails to have these properties will not be an adequate theory of moral duty. Someone else may try to re-define the terms if he wants, but that doesn’t affect the claims we are making in putting forward our two premises. The question is whether our claims, taken as we understand them, are true.

Finally, while I’m inclined to agree that that if objective moral values exist, then the universe has purpose, that is because I think that if objective moral values exist, then God exists, and if God exists, then He would have a purpose for creating the universe. But I don’t see a conceptual connection between purpose and value, which is what your argument appeals to. So I don’t think your introducing purpose does anything to strengthen the argument as it now stands.

- William Lane Craig