This is the weekly Q & A blog post by our Research Professor in Philosophy, Dr. William Lane Craig.


Dr. Bart Ehrman has repeatedly claimed in his debates and written work that group visions of the Virgin Mary in modern times proves that group hallucinations can occur. He spends a significant portion of Chapter 5 of his book "How Jesus Became God" describing these group hallucinations. Is this example truly analogous to the appearances of Jesus to groups of people after his resurrection?


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Dr. William Lane Craig's Response

My friend and colleague Michael Licona has not only studied group hallucinations but has also successfully debated Bart Ehrman. So I’ve asked Mike to write a guest Question of the Week in response to your question. His reply follows:

Hi, Jordan. Dr. Craig has asked me to address your question, since I’ve debated Bart Ehrman on numerous occasions.

A lot of research has been conducted for more than a century pertaining to hallucinations. An excellent book that summarizes the research is Hallucinations: The Science of Idiosyncratic Perception by André Aleman and Frank Larøi, published by the American Psychological Association in 2008.

According to the American Psychological Association, a hallucination is “a false sensory perception that has the compelling sense of reality despite the absence of an external stimulus” (APA Dictionary of Psychology, 2007, 427). Hallucinations should not be confused with illusions or delusions. An illusion is a distorted perception of reality, such as seeing water on a highway on a sunny day, while a delusion occurs when one persists in believing something despite conclusive evidence to the contrary. Someone who refuses to believe that his wife is dead despite having buried her is delusional.

Many years ago, I had the opportunity to ask a few dozen Navy SEALs about their experiences during Hell Week, which is the first grueling test they must pass before becoming a SEAL. Candidates begin Hell Week on a Sunday evening and finish around noon on the following Saturday, getting only about 3-5 hours of sleep during the entire week. That’s not 3-5 hours of sleep a night but for the entire week! A large percentage of candidates told me they had experienced visual hallucinations during Hell Week due to sleep deprivation. But none had experienced the same hallucination. Moreover, when one candidate pointed out to the others what he believed he was seeing, none then saw what he did. This is because hallucinations are private experiences occurring inside the mind of an individual. Since they are mental events with no external reality, there is no way for people to participate in the same hallucination.

Hallucinations are similar to dreams in this sense. I could not awaken my wife in the middle of the night and say, “Honey, I’m dreaming I’m in Maui. Go back to sleep, join me in my dream, and let’s have a free vacation!” She may dream she’s with me in Maui. But it’s not going to be the same dream. And any interaction with me in that dream is not something in which I would actually be participating.

Now that you have an idea of the nature of hallucinations, let’s discuss Ehrman’s contentions pertaining to visions of Mary in his book How Jesus Became God. There, Ehrman makes numerous errors in his assessment of group visions. First, he merely assumes without any argument that visions of Mary are hallucinations. He states that groups had seen her (198-99). He admits that many of those experiencing the visions were educated professionals, including doctors, psychologists, psychiatrists, engineers, and lawyers (198). Even Muslims apparently saw her (199). And the person perceived as being Mary was even photographed (199).

But are these observations compatible with group hallucinations? We’ve observed that groups cannot experience hallucinations. Certainly, Muslims would not be inclined to experience hallucinations of Mary. And, since hallucinations have no external reality, they cannot be photographed. Therefore, whatever these people experienced, they were not hallucinations. I once emailed Aleman and Larøi, coauthors of the above mentioned book on hallucinations, asking why they did not mention group hallucinations in their book. Larøi replied that they had intended to do so but were unable to find any documented case in which a group had experienced a hallucination. A group can experience an illusion or be delusional. A group can also have a similar interpretation of something that its members perceive, such as when a group saw an image in mirrors on a building that its members interpreted as Mary. But these are not hallucinations.

Second, Ehrman faults Christians for appealing to evidence for miracles supporting their Christian beliefs while rejecting similar evidence for miracles supporting other religions. While I cannot speak for other Christians, I can speak for myself. I do not deny that miracles can occur in other religions. God may choose to act within another religion in order to get the attention of some of its adherents. Other supernatural forces, such as demons, could be behind some supernatural events in other religions. Some will scoff at such an idea. But anyone who has some familiarity with the occult or Voodoo knows that demonic actions are a part of reality, and a scary one, too!

Third, Ehrman is inconsistent when accusing others of the same. He says “most people at the end of the day believe that mass hallucinations are not only possible, but that they really can happen. Precisely those conservative evangelical scholars who claim that mass hallucinations don’t happen are the ones who deny that the Blessed Virgin Mary has appeared to hundreds or thousands of people at once, even though we have modern, verified eyewitness testimony that she has” (202). I do not know if “most people” think that mass hallucinations occur. However, even if they do, I’m more interested in knowing what mental health professionals who have conducted serious research pertaining to hallucinations think. And if Ehrman insists on relying on what “most people” think as an argument, he should likewise consider that, by far, “most people” believe God exists. Yet, that has not persuaded Bart to think He does.

In my debates with Ehrman, when he has raised the topic of Marian apparitions, I have responded that I do not doubt that the percipients saw something. What they saw is what I question. Elliot Miller and Kenneth Samples coauthored the book The Cult of the Virgin: Catholic Mariology and the Apparitions of Mary (Grand Rapids: Baker, 1992). In this book, they discuss the three major accounts of Marian apparitions: Lourdes, France; Fatima, Portugal; and Medjugorje, Croatia. I know Samples personally. He has interviewed several of the seers to whom Mary has appeared in Medjugorje. Although Samples is a Christian whose Protestant theology does not incline him to believe that Mary has appeared to others, he is convinced that these seers have seen a spirit being. In fact, I had an opportunity to inquire further of Samples on the matter. He told me that several of the seers in Medjugorje continued to have visions of Mary. In fact, he was with one of the seers while he was experiencing such a vision, although no one else in the room saw her. Samples told me he asked the seer if Mary had ever spoken to him. The seer said she had, recommending a specific book which the seer was to read. When Samples looked up the title of the book, it was occultic. This led him to believe that a demonic spirit is what is appearing to the seers.

In summary, Bart offers three arguments for mass hallucinations. He appeals to visions of Mary by groups. Yet, he merely assumes without argument that these were hallucinations. Since hallucinations are mental experiences with no external reality, group hallucinations are not possible. That apparitions of Mary were experienced by groups, were experienced by Muslims, and were even photographed strongly suggests these were not hallucinations. Ehrman faults some Christians for denying that supernatural events occur in other religions while accepting their own uncritically. Yet, such denials are unnecessary, and I’m not aware of any Christian apologists who do so. Ehrman claims that a majority of people believe mass hallucinations occur. Yet, if he followed his own line of reasoning, he should likewise conclude that God exists, since a majority holds that God exists.

So, Ehrman’s arguments fail to convince. But is there evidence that the resurrection appearances of Jesus were not hallucinations? Let’s take a look at our earliest report, which appears in 1 Corinthians 15:3-8. Here Paul is citing an oral tradition that most scholars hold goes back to a very early date and is tied to the Jerusalem apostles:

For I delivered to you as of first importance what I also received. That Christ died for our sins according to the Scriptures. And that He was buried. And that He was raised on the third day according to the Scriptures. And that He appeared to Peter, then to the Twelve. Then He appeared to more than five hundred brethren at one time, most of whom still remain alive, although some have died. Then He appeared to James, then to all of the apostles. Last of all, as to one untimely born, He appeared also to me.

Here are four reasons why it is highly unlikely that the appearances of the risen Jesus were hallucinations.

First, the percentage of percipients is too high. Notice that the report states “the Twelve” and “all of the apostles” claimed the risen Jesus had appeared to them. That’s 100 percent. However, Aleman and Larøi report that an average of only seven percent of those grieving over the recent loss of a loved one experience a visual hallucination of that loved one (67). Thus, the percentage of the disciples who were percipients of the risen Jesus is far too large for reasonable consideration of hallucinations.

Second, the report states that three appearances were to groups: the Twelve, more than 500, all the apostles. Recall that hallucinations cannot be shared, since they are events in the mind of individuals and have no external reality.

Third, the appearance to Paul was unlikely a hallucination, since Paul was certainly not grieving Jesus’ death. After all, he had regarded Jesus as a false prophet and failed Messiah figure. His goal was to destroy the movement that Jesus had started. So, Jesus would have been the last person in the universe Paul would have wanted to see or expected to see.

Fourth, hallucinations would probably have led to the conclusion that Jesus had been exalted by God in heaven and would not account for Jesus’ empty tomb.

In short, Jordan, Ehrman’s arguments for group visions of Mary fail quite miserably to account for the resurrection appearances of Jesus. And we have very good reasons to think that the nature of the disciples’ experiences of the risen Jesus were not hallucinations.

This Q&A and other resources are available on Dr. William Lane Craig's website.