A Mathematics of History?
Before diving into the contents of Richard Carrier’s On the Historicity of Jesus (OHJ) I need to say a bit about the method he uses to organize his conclusions. Prior to this book Carrier wrote a book called Proving History. It was entirely concerned with what methodology he would be using to answer the question of Jesus’s historicity. It included a primer on historical inquiry in general, a critique of the methods biblical scholars use to “extract” historical information about Jesus from the gospels, and a defense of using Bayes’ Theorem in historical inquiry.
The Critique
Biblical scholars for some time have used various criteria which they claim allows them to separate the fictional elements of the gospels, added by the church, from the historical elements. Or, at least they claim it increases the likelihood that some element is historical. For example the criterion of embarrassment says if an element of the story would be embarrassing to the church it is not likely they would have invented it.
The criteria have come under strong criticism within the field. The logic of them often is not sound and scholars apply them in situations where they aren’t applicable, or apply them inconsistently. Indeed the history of their use is not very encouraging as each scholar who sets out to paint a picture of “the true historical Jesus” comes back with a different picture. Carrier cites a lot of this critical scholarship and adds his own critique. I’ll just give one example and summarize the analysis given by Carrier (which I agree with).
One of the supposed bedrock truths scholars have extracted from the gospels is that Jesus was baptized by John the Baptist. The criterion of embarrassment is invoked. Here is Jesus being portrayed as in some sense subordinate to John. In addition John’s baptism was for the remission of sin and wasn’t Jesus supposed to be without sin? Thus, the reasoning goes, this must have been something everyone knew about and it just couldn’t be avoided. Mark was written first and Matthew and Luke copied much of their material from him (often word for word, or nearly so). Matthew and Luke have tinkered with this story to make it less embarrassing.
It is a reasonable argument but there are several problems. The later gospel authors seem to have no compunction about altering stories to fit their agendas. They omit elements when it suits them. Why would Mark be any different? If he was embarrassed by this story why did he include it in the first place? In fact Mark shows no signs of embarrassment at all in telling this story. Let’s not forget that Mark was written roughly 35 years after Jesus would have lived. So are we to imagine the story of Jesus being baptized by John circulated for three and a half decades and no one noticed it was embarrassing? No one had already tinkered with the story before it reached Mark (and thus he would have already been reporting the apologetic in his gospel)? Suddenly, after Mark wrote his gospel, everyone finally noticed it was embarrassing and scrambled to explain it!
When you think it through it is a rather silly scenario. In fact, the actual sequence of events suggests quite the opposite of what the biblical scholars have concluded. Mark being completely unembarrassed by the story followed by signs of embarrassment after Mark wrote suggests that no one had heard the story before because Mark invented it! Either that or it simply wasn’t embarrassing to those that came before, but if that is case the criterion of embarrassment doesn’t apply!
I’ve gone one far longer than I intended so I’ll just leave it at that. I’ll just say I think Carrier, and the critics from within the field, have successfully called into question the validity of criteria based methods.
Bayes’ Theorem
The challenge facing anyone examining a complex historical scenario is this. Each individual artifact or document could have had several causes and in most cases you cannot rule out all but one of them. So how do you evaluate your overall thesis if each piece of evidence only partially supports it? Also, it will often be the case that some pieces of evidence are more likely on one theory but other pieces suggest another (while not ruling out the first one). Clearly what is needed is some way to state how much weight each piece of evidence carries, and by how much it favors one theory over another. Finally, there needs to be some way to combine those individual judgments in a fair and rigorous fashion.
That’s where Bayes’ Theorem comes in. Bayes’ Theorem is an equation in probability theory specifically geared towards comparing one hypothesis with another (or, rather, one hypothesis with its negation). If we can state our evaluations of the evidence in terms of probabilities (or ratios of probabilities) then we can use Bayes’ Theorem to combine them, giving us a number at the end that states how likely it is the theory we are considering is the cause of the evidence we have. Obviously that number is entirely dependent on how sound our evaluations were but at least it gives us a principled way to combine them while at the same time allowing others to see how we’ve weighted the evidence.
Carrier defends the use of Bayes’ Theorem in Proving History and responds to most of the common objections people advance. I’m not going to spend a lot of time on that material. I think it is an interesting subject and I may discuss it during the course of this series but for now I think it is enough to say that using Bayes’ Theorem seems reasonable enough. In OHJ Carrier simply tallies how strongly he thinks a piece of evidence favors one theory or the other, e.g. 5/4 in favor of mythicism, or 1/1 if it doesn’t favor either, etc. To combine them one simply multiplies the individual factors together to get a final ratio that tells you which theory is indicated by the evidence and how strongly.
So what do those ratios represent? I like to think of it in terms of the scientific method we all learned in school. The idealized scientific method is often presented as hypothesize, enumerate predictions, gather data, reach conclusions. The ratios represent the ‘enumerate predictions’ part of this picture. What we are doing is taking a hypothesis as a given, i.e. assuming it is true, and then asking ‘of all the possible worlds that could result with this hypothesis being true, what percentage of them will contain the piece of evidence we are evaluating?’ Then we do the same for the hypothesis we are comparing it to (or the combination of all hypotheses that aren’t the first one). Dividing the first by the second gets us our ratio. So if our ratio is 2/1 in favor of historicity, for example, we are saying a historical Jesus will produce the evidence twice as often as a mythical one will.
It should be noted that there is a certain level of generality involved here. If examining a document for instance, we aren’t asking how often that specific document with exactly the words it contains will arise. We are asking instead about general features of the document. Carrier mounts a defense of this approach in Proving History and I think it is generally sound, however I would point out it introduces another place where subjectivity can enter the picture. Which features are important and which features can be abstracted away?
There is one more feature of Bayes’ Theorem that must be mentioned. When you use it you must estimate the prior probability of the hypothesis you are testing. That is, before you even begin looking at evidence how likely is your hypothesis, based on your more general knowledge of the world? Carrier uses a scale, developed by Rank and Raglan, of traits often found in hero tales, on which Jesus scores very high. Though historical people sometimes have several of the traits, that arise in legends about them, no historical individuals score nearly as high as Jesus and the high scoring mythical beings. From this Carrier justifies starting with a prior probability that Jesus was historical of 33% (i.e. 1 in 3, or 2/1 against).
I’m not going to examine the issue of prior probability very closely at the moment. Nor will I be relying on his 33% estimate. The more important question is which hypothesis does the evidence favor, and by how much? If the evidence favors one hypothesis much more strongly than the other, then it won’t really matter much what prior you started with; it will be overwhelmed by the evidence. If the evidence is fairly close, then determination of the prior will become more important and can be pursued then.
How Did Christianity Begin?
Biblical scholars and historians have established beyond the shadow of a doubt that the Jesus of faith, as described in the New Testament, is more myth than history. Was there an actual person, however, that inspired the tales? This series of posts examines one historian’s case, published by an academic press specializing in biblical scholarship, that maybe there wasn’t. That historian is Richard Carrier and the book is On the Historicity of Jesus: Why We Might Have Reason for Doubt (OHJ) (also available through Amazon).
The idea Jesus didn’t exist enjoys very little support within academics, however, not none. In 2012 respected Biblical scholar Thomas Brodie published his memoirs where he revealed he hadn’t thought there was a historical Jesus since the 1970’s. As his Wikipedia entry details, the Catholic church wasn’t too happy about it.
There is also Thomas Thompson a scholar who helped to overturn the notion that the Biblical patriarchs, like Abraham, were historical individuals. He has adopted an agnostic stance with regards to a historical Jesus. His view is that, whether or not there was a historical Jesus, there is no need to refer to him to explain the documents of early Christianity we have. The cultural setting and theological agendas of the Biblical authors are enough.
Robert Price is certainly more than qualified to have an opinion on the subject, with two relevant PhDs, and having participated in such venues as the Jesus Seminar. In his The Christ-Myth Theory and Its Problems he details how just about every bit of the Gospels appears to be derived from stories in the Old Testament, retold about Jesus. That being the case what need is there to propose a historical Jesus? On this basis, among others, Price thinks it unlikely there was such a person.
There are a couple of others that could be included in the agnostic camp but that’s about it (that we know of). There is however at least one scholar who, despite thinking there was a historical Jesus, sees value in discussing the notion of a mythical Jesus openly in the field.
Given the otherwise consensus view in favor of a historical Jesus, a reasonable stance for anyone not wanting to spend time on the question is to just trust the experts and be done with it. No one can investigate everything themselves and, as long as the experts seem to be doing rigorous work, trusting them seems a reasonable course.
Others might not quite trust the experts in Biblical studies. After all the field is overwhelmingly composed of Christians with confessional interests to protect. There is some validity to this concern, and an apologetic tendency can be traced within the field. When Thomas Thompson, mentioned above, published his work arguing against the historicity of the patriarchs there was a massive, knee-jerk, reaction to the work that saw his dissertation suppressed and him eventually driven (temporarily) from the field. Today though most everyone accepts he was right after all. Still, even if one doesn’t trust the experts, that at most argues for being agnostic about the question, if one hasn’t investigated it themselves.
Personally, despite its shortcomings, I think the field generally does its work with competence. We’re not talking about fundamentalists here (especially since there are some secular people in the field as well). I think there is a legitimate respect for the scholarly enterprise and researchers in the field are trained in the relevant languages and the relevant documents and approach the subject with care and reason. That doesn’t mean, however, they’ve got everything right! Nor does it mean they display competence and rigor on every subject.
I’ve opted for a third option: examine the evidence and try to decide for myself. Not possessing the specialized knowledge of the experts puts me at a disadvantage, obviously, but I believe that is a reasonable course for a layman to pursue if done carefully (and with some degree of humility).
The Theories
In his book Carrier compares two theories with the goal of deciding which one the evidence best supports. I’ll just give a shortened (and paraphrased) version of each.
Minimal Historicity (OHJ Ch. 2):
An actual man named Jesus acquired followers during his life who continued as a recognizable movement after his death. Some of those followers claimed he had been executed by the Jewish or Roman authorities and soon began worshiping him as a living god or demigod.
Minimal Mythicism (OHJ Ch. 3):
Christianity started with a Jesus Christ who was a celestial deity (existing only in the heavens). Jesus ‘communicated’ with his subjects through dreams and visions. He was believed to have undergone incarnation in human likeness, death, and burial in the supernatural realm. Later allegorical stories of this Jesus were written that placed him instead on earth. Later communities believed and/or taught that the invented allegorical stories were real.
The second theory isn’t exactly new. Almost 20 years ago, in 1996, Earl Doherty started promoting this idea on his website and in 1999 published a book called The Jesus Puzzle. Carrier has refined the theory and the arguments supporting it in order to meet the standards of an academic press.
Doherty had noticed what many scholars had. The documents we have from before the gospels, the epistles (letters) of Paul and others don’t seem to care anything about, and don’t tell us anything about, the life of Jesus on earth. They relate the crucifixion and resurrection of course, but never explicitly place it on earth. As to any of the other details of Jesus they seem to care not one whit. Nothing about a ministry or any teachings, no direct quotes of Jesus except ones said to be received in visions, no cleansing of the temple, no healings or exorcisms, no empty tomb, and no talk of disciples (only apostles). The only gospel event mentioned directly, the Eucharist, Paul says he saw in a vision directly from Jesus in heaven.
Think of how strange that is. Supposedly God’s chosen son (in their view) had just recently been walking the earth and no one seems to care to mention anything he did. Imagine any modern day preacher writing 20,000 words (roughly the combined word count of Paul’s letters) about Jesus and never mentioning anything he did on earth! It seems all but impossible today and, despite the excuses trotted out to explain it away, it has seemed equally strange to many scholars of the Bible. Maybe it is because the story of Jesus walking the earth hadn’t been invented yet.
Now it should be said that some have tried to read the gospel stories back into the epistles. Examining a particular passage or other, they say it must be referring, obliquely, to an event, or quote, mentioned in the gospels. It is possible they are right, in which case there are a handful of such mentions after all. There are also a handful of passages that, while not relaying a particular gospel story, seem to be either referencing or outright stating an earthly existence. If a theory of a mythic beginning is to prevail it is going to have to explain these passages. It must be pointed out however that every theory about Jesus has such passages to overcome, including that he was a historical person, and Doherty and Carrier have highlighted several such passages that are hard to explain on the assumption that Jesus lived.
My Personal Take
My opinion has evolved over the years. I don’t really care what the answer is; the Jesus of faith is certainly not true either way. I must admit however that I find the subject fascinating. Originally I was a bit awestruck by Doherty’s thesis and I still think it would be really cool if it was true; much more interesting that the historicist theory. However, before reading Carrier’s book the first time through my opinion was that there is just enough evidence to support the existence of a man named Jesus who inspired the Christian religion. I now plan to read it again and to use the framework Carrier provides to see how my final judgement comes out. That’s what I’ll be doing in these posts.
What’s Next?
Unfortunately before diving in I’ll probably need one more preliminary post on Carrier’s use of Bayes’ Theorem as the framework for deciding the question. Really I just want to dive right in and not spend a lot of time laying the ground work, such as discussing the current techniques used in biblical studies, or cataloging all the potential sources of evidence, etc. After the post on Bayes’ Theorem I want to look at a couple early Christian documents that provide a model for the mythicist theory.
A Note on Comment Policy
I understand there are a lot of strong feelings on this subject. Some Christians simply cannot abide it. Some atheists as well can get pretty upset by it feeling that it makes atheists look bad considering the academic consensus (or as a proxy war in some intra-atheist feud or other). Other atheists, despite often knowing little to nothing about the subject, are insistent there is absolutely no evidence what-so-ever for Jesus having lived.
Anyone who is a friend is free to ask whatever they like but everyone else should know that I’m going to be a bit of dictator with any comments. Stay on the topic on the post, don’t cheerlead or “me too”, try to provide a reference for any claims you make, and don’t bash or slur other groups (atheist or Christian). I’m doing this for myself and not to convince anyone else of anything so I’ll have very little patience for any non-sense.
Carrier has spent considerable time on this book, and has managed to meet the standards of an academic publisher that specializes in biblical studies. That doesn’t mean he is right but it does mean that it deserves to treated seriously. I’m not interested in rationalizations you have come up with for dismissing it out of hand.