Although it is certainly true that we do not have ancient people to use in our experiments, the conclusion that we can't learn anything valuable and shouldn't bother experimenting or relying on psych literature is not a justifiable conclusion. What it amounts to is an excuse to keep us all in the dark about the impact human memory had on the Jesus traditions and how materials were actually composed in a world in which literacy was so low that an oral consciousness even dominated the written word and scribal practices.
Why do we want to be kept in the dark? Because it allows us to conclude whatever we want to from our ancient sources, with no justification beyond that it might sound good to us? This way we can keep the red letter edition of our bibles and we can write assuredly who the historical Jesus was?
But the facts are these. The only way that we have the actual verbatim words of Jesus is if someone followed him around and recorded in writing immediately everything he said with 100% accuracy, and then this document was copied with no errors into other documents. Or if someone with a very good short term memory spoke immediately what he had heard to the next person who also had a very good short term memory and so forth until it was written down with 100% accuracy. Since neither of these processes are likely, we can forget the red letter editions, and we can forget knowing what he said verbatim or who the historical Jesus was beyond the broader strokes.
What about trained discipleship, where Jesus was the teacher teaching his disciples to memorize his words? For those who like this model, it must be kept in mind that such training, if it existed (which I seriously doubt in the case of the Jesus movement since this is nowhere found in our Christian sources) was not about verbatim memory. It was about remembering the central teaching and a few words, and reconstructing from memory the best one could. The ancient people knew that their memories, even trained, were not that accurate. This is why the rabbis had all kinds of magical spells to try to improve their memory of the Torah! Our notion of memorizing is based on our knowledge of literacy, where we have texts that we can read over and over and over again, test our memory of it for accuracy, and keep working on it like this until we get it into our long-term memories. But this is not the way of the ancient world, where most memory work had to be done orally with little to no reference to written words. What one can remember in this type of learning environment is very different from the literate "memorizing" we all think about today.
In order to know how this process worked and how it might have affected the composition of our texts, it is essential in my experience to experiment and to read in cognitive psychology which tells us how human memory operates and affects the transmission process. When we compare the results of this knowledge with what we see in our texts, it is really quite amazing what we can learn about the ancient people processes.
Let me give an example that I mentioned too in the SBL session. Professor Goodacre points out that on several occasions Thomas fails to narrate the middle part of a given parable, making the ending almost unintelligible. He uses the Parable of the Wheat and Tares as a clear example of this. He concludes that this clumsiness comes from Thomas’ familiarity with the Synoptic stories, when he rushes to retell the familiar story, rather like someone who can’t tell a good joke, he rushes ahead to the punchline and leaves out the middle.
What is the evidence that writers who have a literary document in front of them from which they are copying ever leave out the middle because they are rushed? Just based on logic, I would think that literary copying would be otherwise. That the copyist would be more careful to preserve the material he is using, that he is working slowly, that he can stop and go back and double check, and that he can erase and correct. Such is not the case, however, when an author is relying on human memory, when he cannot double check a written source. Even more so for the author who is composing orally, when in fact he really is like a teller of jokes who forgets the middle to rush to the end, and who cannot stop and redo it, or erase what he has just said because he is speaking, not writing, as he composes. But this is just my logic, it is not based on any scientific data.
So what about scientific data? What experiments have been done that might help us? The subject of memory distortion is its own field of study within cognitive psychology, but most studies on errors of commission generally try to explain why memory distorts rather than how it distorts. Although there has been related work done in the field of cognitive psychology on the instability and stability of human memory, the only experiments conducted that might help with the questions we have about literary dependence is the work of McIver and Carroll (JBL 2002, Applied Cognitive Psychology 2004). So I went after a grant and set up my own pilot experimental exercises with the help of Professor Jean Pretz, a cognitive psychologist at Illinois Wesleyan University where I was a professor at that time. I have just published the results in Tom Thatcher’s volume, Jesus, the Voice, and the Text, "Human Memory and the Sayings of Jesus: Contemporary Experimental Exercises in the Transmission of Jesus Traditions," so I refer you to that article for all the supporting data. I want to emphasize that the results are based on only forty-four subjects and my goal was only to run a short pilot – to test the waters and see if my results warranted further experimentation on a larger-scale that would be able to generate more-significant statistical data. Even though these findings should be tested further, the results are in line with the results of other studies conducted by psychologists who study human memory.
One of these relates directly to Professor Goodacre’s example. In my experimental exercises, I asked different groups of students to transmit proverbs, parables, and miracles stories in different media environments. I found that the traditions that relied on human memory for transmission suffered drastic condensation and remodeling, even to the point of becoming nonsense. The psychological experiments of Professor Bartlett in the 1930s proved this as well (Remembering, Cambridge, 1932). Whenever a person was asked to recount from memory a story, and it was written down, the narrative was denuded to an undecorated tale. Bartlett noticed that only the main points were left, the central motifs.
This is not to say that details weren’t added. They were, and when this happened, they usually were features more contemporary or idiosyncratic, representing the view, and as Bartlett called it, the rationalization of the tradent. Even so, moderate expansion was not the norm in any of the memory environments that I studied. But it was the norm for the words to be condensed into something more easy to recall.
Data from my own experimental exercises not only support Bartlett here, but further suggest that the lost of details happens mostly in the middle of the reproductions just as we see in Thomas 57. I might add further that the entire saying displays the characteristics of an orally transmitted parable. It commonalities with Matthew’s version amount to a few memory trigger words like “good seed”, “enemy came,” “pull out the wheat,” “harvest” and “burned.” Although the general message of the parable is maintained across the versions, the details and presentations are strikingly different. Thomas’ version has been abridged over the years of its oral performance to the point that the antecedent “them” has been lost. Matthew’s version has been expanded during its transmission so that it contains secondary features that appear to reflect the theological interests of Matthew, such as the dialogue about the “enemy” in vvs. 27 and 28 and the accumulated proverb in v. 30. Both versions suggest that each author received something older, yet exactly what that older version was is impossible to determine. The reason for this is that in the oral sphere we can have no single originating version from which we can create a family-tree of dependent versions.
Let me know if you want to hear more about this subject. I will gladly post on it. But this particular post is getting too long for a blog.