The centerpiece of The Christian Delusion seems to be the Outsider Test for Faith. Here is Loftus's presentation in TCD:
1. Rational people in distinct geographical locations around the globe overwhelmingly adopt and defend a wide diversity of religious faiths due to their upbringing and cultural heritage. This is the religious diversity thesis.
2. Consequently, it seems very likely that adopting one's religious faith is not merely a matter of independent rational judgment but is causally dependent on cultural conditions to an overwhelming degree. This is the religious dependency thesis.
3. Hence the odds are highly likely that any given adopted religious faith is false.
4. So the best way to test one's adopted religious faith is from the perspective of an outsider with the same level of skepticism used to evaluate other religious faiths. This expresses the OTF. (82)
It seems to me that we can raise some questions about the first two premises. People today grow up in a culturally diverse world. Perhaps their early religious education may come from one religion or another, but plenty of people get hit with outside perspectives in high school or in college. There are aware that there are other religions. They are aware that there are some who deny the existence of any supernatural beings whatsoever. They know about controversies surrounding creation and evolution.
The cultural influence on people to adopt and be strongly committed to the faith they grew up in is mitigated by numerous influences from many sources. Peer pressure drives young people toward premarital sex, even when Christian groups oppose it. What we get from most media outlets does not drive us in the direction of a serious faith. We may find ourselves wanting to believe, but if we have heard the warnings about wishful thinking, that is going to make it harder, not easier to believe. As a result, even from a relatively early age, our beliefs with regard to religion, we are considering evidence. The image Loftus presented of believers who are "brainwashed" doesn't match a large number of Christians I have gotten to know over the years. In fact, the failure of most Christians to satisfy the stereotype found in anti-religious literature made their views on these matters lose credibility for me.
So the third premise, that one's religious beliefs should be regarded as probably false based on upbringing, seems to be highly questionable, simply because most of us are not only interacting with upbringing, but with evidence.
But now we come down to the test itself. One should approach one's own religion with the same level of skepticism that one approaches other religions. Is that a fair expectation? On one level, it's a kind of "fairness doctrine" for religious beliefs. Don't use a double standard for other religions that you don't use for your own.
At least hypothetically ask yourself if the evidence for your own religion would really be convincing if you weren't a believer.
But if that's all there is to it, then I would have to say that I believe that Christianity has an evidence base that is unmatched in other religions, and furthermore, if I came to think that the Christian evidence base was matched by, say, the evidence base for Islam or Mormonism, that I would probably start having serious doubts about what I believe. Now some of you may wonder how I could possibly believe such a thing, but I do believe it.
Does that mean that my Christianity passes the Outsider Test for Faith? Well, Loftus is going to say that, no, those psychological and sociological influences still have be in their grip.What would be evidence convincing to Loftus that I had passed the OTF? Deconversion, of course.
However, while I believe in pursuing objectivity, I also believe that human beings have no cheap and easy way of setting their intellectual biases aside. Remember Descartes? He knew that he had a lot of ideas and beliefs that he thought weren't justified. And he decided to doubt, not just religion, but everything. And he proved, in the Meditations, that God exists, that the soul is distinct from the body, that the will is free, etc. Would Loftus then say that his beliefs had passed the Outsider Test for Beliefs? Or would he say that he only thought he got outside, but really didn't. But you have to wonder what Descartes could have done that he didn't do.
Loftus makes couple of claims about how Christians deal with other religions, about which need some attention. In dealing with, say, Mormonism, Christians will argue that what Mormons teach conflicts with the Bible. That may be more of an internal critique of Mormonism than we realize, because Mormons, supposedly, accept the authority of the Old and New Testaments as well as modern revelation such as the Book of Mormon.
The other method Christians have of responding to other religions is to take a Humean method of evaluating the evidence and presume methodological naturalism in analyzing those religions. Now, for example, I think that the origins of Mormonism can be explained naturalistically. But that's not because of my method, that conclusion came on the basis of my study of how the religion was founded. There could be information about the evidence base for Mormonism that would make me think twice about whether or not it is true, but as it happens, there isn't. So no, I don't approach Mormonism as a methodological naturalist. In fact, some Christians explain the founding of Mormonism supernaturalistically; they think Joseph Smith was visited by an angel, a fallen angel. I happen to think that is not supported by the evidence. But it could have been, just as it could have turned out that that evidence supports the claim that Moroni was a good angel.
So, his description of how Christians evaluate other religions is off base. To be a real methodological naturalist is to give up on knowing that there has been supernatural activity, even if there has indeed been supernatural activity. I don't believe that the orthodox Christian critique of, say, Mormonism, entails that kind of opportunity cost.
Loftus makes what I consider to be a bizarre claim, in endorsing Richard Feldman's argument that when there are two "epistemic peers" who have a "genuine disagreement" based on "shared evidence," it is rational for both to suspend judgment. This would effectively shut down philosophy if it were followed, and I think it would even shut down science, and it is a very good thing that people don't operate that way. If we go by my credentials, I am certainly Loftus' epistemic peer (actually his superior, since I have a Ph.D and he does not), so since we disagree on God, and even on the legitimacy of the Outsider Test for Faith, he's now obligated to suspend judgment on what he says. Will he follow Feldman's advice? When hell freezes over!
I am deeply skeptical about "default positions." My biggest problem with the outsider test for faith is that there is no outside. If we can imagine all the possible positions with respect to the probability of theism from 100% sure that theism is true to 0% probability that theism is true, I don't see any spot on that continuum that is a default position. I think that, realistically, what real people do is just begin from where they are and conditionalize, as Bayesians say, on the evidence. If there is enough evidence, and we all keep conditionalizing, we'll eventually converge on the truth. I think this is a more realistic way of looking at the process of thinking through controversial issues than is the idea of some neutral "ground zero" to which we should all be expected to move. Maybe part of that comes from my philosophical upbringing; I went through grad school when both in religious philosophy and in secular philosophy I kept hearing about the decline and fall of classical foundationalism. So I don't believe that there is such a thing as a "neutral corner" and I am suspicious of those who think they have gone there.
Yet, I do think the evidence both for the existence of a theistic God, and the evidence for the central claims of Christianity, is sufficiently strong that it should be convincing to an open-minded agnostic, just as it convinced the former atheist C. S. Lewis. If I perform the thought experiment of asking myself what I would believe had I started out from open-minded agnosticism, my answer is still Christianity. I don't think it reasonable for me to actually make myself an agnostic in order to do a real outsider test, but insofar as I perform the hypothetical outsider test, that's the outcome. Now, it could be that I have mis-evaluated the evidence. There are people whom I deeply respect who have evaluated it differently. Now, no doubt Loftus evaluates the evidence differently from the way I do. But that evaluation isn't part of his outsider test argument.
What does Loftus say about that? Well, he gives us the sociological and psychological analyses of people like Eller, Long and Tarico, defending the claim of Shermer's that smart people believe weird things because they are good and defending what they already believe for non-smart reasons. But you can only say that if you have actually shown the reasons that we have for believing what we do to be bad. That step can't be skipped. Of course I know I could have misevaluated the evidence, and there are psychological and sociological mechanisms that might be the causes of that misevaluation. But those same forces affect us all. No deconversion, no "outsider test," is going to save us from making mistakes. C. S. Lewis became a believer, overcoming a considerable emotional resistance to becoming a believer. Loftus says the same thing about how he became an atheist. But crossing from one world-view to another doesn't guarantee the correctness of how one has reasoned..
Loftus writes: So upon what basis do nearly all believers around the world, including Reppert, think they are exceptions if this is the case? They cannot all be the exceptions! Believers are simply in denial when they claim that their religious faith passes the OTF.
But I could say the same thing about Loftus. He has a belief about matters of religion. Atheism is a cultural and psychological phenomenon, just like Christianity, in spite of Loftus's protestations to the contrary. The anti-Christian movement has as sociological and psychological dimension, to be sure, as is the New Atheism. Loftus is subject to sociological and psychological influences. He is subject to confirmation bias. He, and his cadre of debunkers of Christianity cannot be the exceptions. With all the psychologizing in his book, it is rather surprising that he says nothing whatsoever about Paul Vitz's work on the Psychology of Atheism. You see, the more you argue the pervasiveness of human irrationality, the more difficult it is to explain who Loftus and company can be the Knights of Reason who have escaped all the psychological influences and have apportioned their belief to the evidence. I happen to realize how difficult it is to be rational. Because I realize this, I believe that I work harder at it than most people on either side of aisle.
To test this, compare his website and mine. How frequently do I bring something up that is a problem for my Christian beliefs, and try to deal with it. Now, how often does he bring something up that is a problem for atheism, and try to deal with it?
I conclude that while the OTF can be a valuable thought experiment, it hardly provides a basis for an argument against Christianity. It can be only a hypothetical test at best, it cannot be perfectly performed by anyone on any side of the fence, and no one can judge whether any of their ideological opponents has truly passed it.