5 / 06
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#270 Justification of the Moral Argument’s Second Premiss

June 17, 2012

Dear Dr. Craig,

I have recently been working through your book, "On Guard," and had a question concerning the Moral Argument (which I have also heard you use in several of your debates). I have seen it most commonly setup as:

1. If God does not exist, objective moral values and duties do not exist.
2. Objective moral values and duties do exist.
3. Therefore, God exists.

Essentially, I find that although the moral argument has a role in our discussions with atheist and other worldviews, it does not seem to be actual evidence for God's existence, but rather an implication of his existence. An atheist can say that morality (although subjective) has developed from biological and sociological influences evolving into what we now consider to be "right and wrong." Although discussing how we come to know morality says nothing about the ontology of morality, it would seem that the only way a theist can show that an objective moral stand exists is by proving (or providing a greater probability through evidence) that God exists. This is due to the fact that the conversation almost always moves from the ontology of morality to the epistemology of morality. It would seem the only way to clear the air is to determine which worldview is true. My concern may be founded on my own ignorance, but the moral argument would seem to be a one way street in that by showing God to exist, objective morality exists. However, following this line of thought in its reverse proves increasingly difficult without pointing to God, since either side can offer an explanation of how we come to an understanding of morality--which again, says nothing about the subjective or objective nature of morality.

I do find that the moral argument helps to count the cost of either ideology or as you said in your book, "what is at stake." But I do not find that the "cost" should be a reason to accept something as true, since our like or dislike of a truth has no effect on that truth. I guess my point is using objective values to show that God exists and then using God to show that objective values exist would seem to be circular reasoning to me. Can we use the moral argument, as given above, as actual evidence for God's existence and if so, how do we 'prove' or give evidence for objective morality apart from pointing to God?


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Dr. craig’s response


Corey, your question asks, in effect, whether the moral argument, as I have framed it, is not question-begging, since the only justification for believing premiss (2) to be true is believing that God exists, which is the argument’s conclusion, so that one is reasoning in a circle.

I reply that the argument is not question-begging, since the warrant I offer for belief in objective moral values and duties is not God but moral experience (see pp. 141-3 of On Guard). That such an appeal is not question-begging should be evident from the fact that the majority of non-theists, including atheists, believe in the truth of premiss (2) precisely on this basis.

Louise Antony, herself a non-theist, put it so well in our debate a few years ago at U Mass, Amherst: Any argument for moral scepticism will be based upon premisses which are less obvious than the existence of objective moral values themselves. That seems to me quite right. Therefore, moral scepticism is unjustifiable.

The humanist philosopher Peter Cave gives the following example:

Whatever sceptical arguments may be brought against our belief that killing the innocent is morally wrong, we are more certain that the killing is morally wrong than that the argument is sound. . . . Torturing an innocent child for the sheer fun of it is morally wrong. Full stop.[1]

In moral experience we encounter objective moral values and duties, and so, in the absence of some sort of defeater of that belief, we are perfectly rational to hold to it. Moral realism is the default position, and the moral sceptic needs to provide some powerful defeater to overcome it.

One can make the same point another way by comparing, as William Sorley does (p. 128 of On Guard) our apprehension of the moral realm with our apprehension of the physical realm. Just as we can’t get outside our moral perceptions to try to justify them, so we cannot get outside our sensory perceptions to try to justify them. Just as, in the absence of some defeater, we trust our sense perceptions that there is a realm of objectively existing physical objects around us, so we trust our moral perceptions that there is an objectively existing realm of moral values and duties. For any argument for scepticism about our moral perceptions we could run a parallel argument for scepticism about our sensory perceptions. But you’d have to be crazy to doubt the veridicality of your sense perceptions of a realm of objectively existing physical objects. Similarly, until we are given a defeater, we ought to trust our moral perception of a realm of objectively existing values and duties.

Now, as I say, this is not a theistic justification of belief in objective moral values and duties; this is the way almost every moral realist justifies his belief in the objectivity of values and duties. There is no circularity here.

In any case, I’d encourage you to simply ask your conversation partner whether he believes in some objective moral values and duties. Ask what he thinks of examples of moral atrocities. Even if the unbeliever has no justification for believing in premiss (2), so long as he does believe in premiss (2), the argument goes through. Since almost everyone does believe that (2) is true, the debate really comes down to (1). The unbeliever will have to explain how objective moral values and duties can exist in a world without God as an absolute standard and law-giver.

You must resist resolutely the tendency to conflate moral ontology with moral epistemology. If the unbeliever tries to steer the conversation toward epistemology, you must bring the conversation back on track. It is just irrelevant that, as you put it, “either side can offer an explanation of how we come to an understanding of morality.” You could agree with everything the unbeliever says about that: we come to an understanding of morality through biological evolution, societal conditioning, parental influences, etc., etc. All of that is irrelevant to the question of whether objective moral values and duties exist, as you yourself observe.

Of course, the unbeliever might present the socio-biological account as a putative defeater of (2), in which case you’ve got to deal with it. But I do deal with two versions of this objection in On Guard, pp. 142-4. I invite you to reflect on what I say there.

Finally, when I talk about the cost of denying the premisses of a theistic argument, I’m talking about the intellectual cost. A determined sceptic can always deny the conclusion of one’s argument simply by denying one of the premisses. (This calls to mind an observation by Alvin Plantinga that one can reduce someone from knowledge to ignorance by offering him a valid argument based on premisses he knows to be true for a conclusion he simply will not accept!) You want to make the intellectual price tag of atheism as high as you can, in hopes that the unbeliever will come to see that the price is simply too high, that to maintain his atheism in the face of the argument would compromise his intellectual integrity. That is the method of good argumentation.

  • [1]

    Peter Cave, Humanism (Oxford: OneWorld, 2009), p. 146. Thanks to Peter S. Williams for this reference.

- William Lane Craig