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Atheist Professor Confronts Christian Speaker

August 11, 2025

Summary

An atheist philosophy professor challenges Frank Turek on the Moral Argument for God.

KEVIN HARRIS: Atheist professor Dr. Bruce Russell confronted our friend Dr. Frank Turek at one of his speaking engagements at Wayne State University. I find it helpful to see arguments in action sometimes, and here's a case as in so many of your debates where we can hear some back and forth in front of an audience. Dr. Russell says he has debated you. Any remembrances of that you want to mention?

DR. CRAIG: Oh, Kevin, I was amazed when you pulled this one out of the hat. Yes, I debated Bruce Russell years ago at the US Military Academy at West Point. So it was amazing for me to see this again. If anybody's interested, the video of this debate, which was a very good debate, is on YouTube. If you will just search for my name and Bruce Russell's name, it will bring up this video at West Point of our debate on the existence of God.[1]

KEVIN HARRIS: Let's go to the first clip as they begin to discuss morality. Clip number one.

DR. BRUCE RUSSELL: I've debated Geivett and William Lane Craig and Bert Spalding here, but this isn't a debate. So I have to limit what I have to say. So the moral argument. This is one I thought was the worst case that William Lane Craig and Geivett and many other theists make because I think there are necessary moral truths that you can know by understanding the concepts. I think it's necessarily wrong-making to rape someone. I think it's wrong to betray a friend. I think it's wrong to exploit people. I think it's wrong to harm people just for the fun of it, and so on.

DR. FRANK TUREK We agree. The question is what justifies that being wrong?

DR. BRUCE RUSSELL: The answer is it's a conceptual truth like the truth that knowledge requires true belief or the truth that, oh, I don't know, 2+2=4.

KEVIN HARRIS: Now, Dr. Russell acknowledges later that math and ethics are different categories. But apparently he thinks that there are necessary moral truths in the same way that there are mathematical truths, and we can understand the concepts. And he said some things are wrong-making which kind of reminds me of Plantinga talking about truth makers.

DR. CRAIG: I think we can all agree that there are necessary moral truths, but Russell's assumption seems to be that necessary truths neither need nor can have explanations. And I think that's evidently false. For example, it is necessarily true that states of consciousness exist. But the explanation for that is that God, a necessary being, exists. And because God exists, it is necessary that states of consciousness exist. Or, to give a non-theological example, it is metaphysically necessary that time travel is impossible. But the explanation for that necessary truth is that time is essentially tensed and temporal becoming is real so that the future does not exist. So I think that necessary truths can and often need deeper necessary truths as explanations. Now, I think Frank somewhat misleads when he says the question is the justification of these truths. Rather, what he ought to have said is the question is the explanation of these truths. What is the explanation why certain moral propositions are true? And I think it's quite evident that they are not conceptually true like 2+2=4. The proposition “It is wrong to betray a friend” is not true by definition. So, it seems to me that Russell is quite wrong on a number of fronts here.

KEVIN HARRIS: Here's the next clip. Clip number two.

DR. BRUCE RUSSELL: That doesn't mean that everyone always believed these necessary truths. I think it's a necessary truth that slavery is wrong. That of course doesn't mean that everybody believed it. But there are many examples in logic and math where people believe false things and only later came to see that there were truths that were necessary truths that they thought were false.

KEVIN HARRIS: Concepts he's talking about.

DR. CRAIG: I'm not sure the context here of [Bruce’s] remarks, but I think that the issue is not how we know these propositions to be true. Rather, it is what explains their truths. Over and over again in discussing the moral argument I have tried to emphasize that the issue is not moral epistemology, but moral ontology. It is not about how we know these moral truths. The question is what explains these moral truths. But even taken as an epistemological question, I think it's clear that these moral propositions are not conceptual truths like arithmetic truths. They are not true by definition. As I thought about this, Russell's example of arithmetic truths actually backfires on him because mathematicians do not take the truths of arithmetic like 2+2=4 or 3+3=6 to be simply a blizzard of independent necessary truths. Rather, they consider these arithmetic truths to be theorems which are deduced from more fundamental axioms; namely, the axioms of Peano arithmetic. That's not “piano” (like a musical instrument); it’s Peano (from Giuseppe Peano) who articulated the fundamental axioms from which these truths of arithmetic are derived. So Russell's own example backfires on him. The necessary truths of arithmetic can have an explanation in these deeper truths that are the Peano axioms.

KEVIN HARRIS: Frank presses further in this next clip. Check this out. Number three.

DR. FRANK TUREK The question is if there is no God, what is the standard that says murder is wrong and rape is wrong and love is good? And why are we obligated to obey it if there is no God?

DR. BRUCE RUSSELL: That's equivalent to the question for me: “How do we know that 2+2=4 if there is no God?” The answer is we know that 2+2=4 independent of any kind of evidence or knowledge of God because we understand the concepts. And though morality is not about numbers, it's about wrongness. And there are certain concepts that are linked necessarily to wrongness like rape and exploitation and the list I partly went through.

KEVIN HARRIS: Wrongness. So we can know that 2+2=4 whether God exists or not. Then we can know that certain moral truths or certain moral acts are wrong apart from God. Bill?

DR. CRAIG: Now here Frank gets to the issue of moral ontology. What explains the truth of these moral propositions? And unfortunately Russell is still focused on moral epistemology: how we know these moral truths. And he should know better because I and other theists whom he's debated have not argued that we must believe in God in order to know that we should love our children or not betray our friends or that rape is wrong. None of us has argued that in order to know those moral truths, you need to believe in God. So Russell is simply barking up the wrong tree here rather than engaging with Frank's argument.

KEVIN HARRIS: Here's the next clip. Frank again asks about moral obligation.

DR. FRANK TUREK Why do we have a moral obligation if there's no purpose to life?

DR. BRUCE RUSSELL: Oh, because we can have obligations that are not tied to purposes. We're not all consequentialists about morality, so you can have breaking a promise can be wrong.

DR. FRANK TUREK Why?

DR. BRUCE RUSSELL: Well, look, this is a question I think you're asking me is why is 2+2=4. That makes no sense. If you agree that it's conceptually necessary that if you rape somebody, you do something wrong, then it makes no sense to ask, well, how can it be wrong if there's no purpose in life or so forth? 2+2 would equal 4 regardless of whether God exists or not.

KEVIN HARRIS: A lot there to talk about. He says, "Not everyone holds to consequentialism."

DR. CRAIG: I'm not sure why Frank brings up purpose in life here, but I think it causes Russell to go off on another tangent against consequentialism in ethics, which is not the issue. The issue rather is that moral propositions are not true simply by definition as Russell seems to think.

KEVIN HARRIS: Propositions come up next in this clip here. Clip number five.

DR. FRANK TUREK How would 2+2=4 be true if nothing existed?

DR. BRUCE RUSSELL: Well, if nothing existed, I mean, even the proposition 2+2=4. It couldn't be, but there's a proposition 2+2=4 that's necessarily true. And so there are propositions as well as lecterns and microphones and professors.

KEVIN HARRIS: There's some controversy there. He thinks that propositions are as real as microphones, lecterns, and professors.

DR. CRAIG: Frank is, of course, right that if nothing existed, then no propositions would be true because there wouldn't be any propositions. But Russell's position is that propositions exist necessarily. Now this gets into really deep weeds in the field of meta-ontology which I've written about in my book God Over All. It was funny when Russell said that lecterns exist, I thought he said “left turns” exist, and I thought left turns and right turns – those are precisely the sort of things that do not exist as mind-independent objects. And in the same way, I don't think that propositions exist. I defend a deflationary view of truth, and this is laid out in my Systematic Philosophical Theology volume one in the prolegomenon where I discuss different views of truth. I don't think we need to go there now, but let me simply say that if listeners are interested you can look at the prolegomenon of that volume one and find a discussion of these views of truth.

KEVIN HARRIS: He may have said left turns, Bill. I thought he said lecterns; you know, microphones, lecterns. If I heard you right there, you do have some new material on propositions?

DR. CRAIG: The material on the deflationary view of truth in the Systematic Philosophical Theology is not new there. It comes out of my work on God and abstract objects which can be found in the book I referred to, God Over All. So if you want a fuller exposition, look at that book. But if you want a précis – a shorter version – look at the Systematic Philosophical Theology.

KEVIN HARRIS: Yeah. OK, here's the final clip. Clip number six.

DR. FRANK TUREK I'm asking for the grounding of those things. Obviously, math and logic are not moral issues. Morality is an obligation.

DR. BRUCE RUSSELL: The only arguments you give for the grounding in God are inferential arguments just of the same sort but with different conclusions. You have ontological conclusions that are based on inference to the best explanation. And I have exactly the same kind of argument to infer that there are necessary truths that don't require God's existence.

KEVIN HARRIS: Well, they pretty much decided to end the conversation there. Frank points out again later on in their exchange that mathematics and moral values are not in the same category, especially with regards to obligation. But Russell says that his arguments for grounding morality are just as good as theistic explanations.

DR. CRAIG: I think that Frank is right to focus the question on the issue of grounding or moral ontology. That is to say, what explains why certain moral propositions are true, especially propositions about moral obligations? Why am I morally obligated to do certain things and morally forbidden to do other things? Russell is simply wrong to think that necessary truths cannot have deeper explanations. Think of the counterexamples that I gave earlier. And, similarly, you can give a deeper explanatory account of the source of our moral obligations through divine command theory such as I've defended.

KEVIN HARRIS: As we wrap up, when I listen to exchanges like this on this topic, my ears are always perking up seeing how they handle the is-ought problem. And Dr. Russell seems to understand the is-ought problem and tries to answer it. Is he successful?

DR. CRAIG: Well, I think he is askewed in his analysis because he thinks of this as an epistemological problem. He wants to know how do we know that we ought not to betray our friends? How do we know that we ought not to torture innocent people? And that's not the question. It's not an epistemological question. The question is whence come these moral obligations and prohibitions if there is no moral lawgiver. And Russell has no good answer to that question, I'm afraid.

KEVIN HARRIS: Hey, just one quick word before we go. If this podcast has encouraged you, I want to encourage you to consider giving back. Reasonable Faith is a completely listener-supported ministry and your donation helps us do what we do each year, whether that's Dr. Craig's writing of his Systematic Philosophical Theology, our animation videos on the attributes of God, or the podcast you just listened to. Help us reach more people with the truth of the Christian faith by partnering with us today. Just go to ReasonableFaith.org and click donate. Every gift makes a difference. And thank you very much.[2]

 

[2] Total Running Time: 17:44 (Copyright © 2025 William Lane Craig)