Simple comme bonjour
It’s early in the morning, but this article has already completely spoiled my day: “Burial cloth found in Jerusalem cave casts doubt on authenticity of Turin Shroud“.
No, it does not cast doubt, because we know that the Turin Shroud is a medieval forgery. So why does this archaeologist answer questions about it? There are quite a lot of people who understand the basic principle of radiocarbon dating. Many people have had chemistry classes at high school, and even more people understand the gaussian curve that explains why it is so bloody unlikely that an object dated to 1325±35 can actually be from the first century.
The article illustrates a mistake many academicians make when they are asked to explain something to the press: underestimating that there are many people who are pretty well-educated. When talking to the press, academicians consistently ignore that in developed countries, up to 50% of the population at some time in their lives enter higher education.
My favorite example is an ancient historian from Cambridge who explained something about Constantine‘s conversion on TV, causing my girlfriend to say that she already knew this from her history classes long time ago. If this was the level of Cambridge historians, she added, she could only despise them. It was a bit exaggerated, but when you see a historian, a classicist, or an archaeologist on TV, it is hard not to start writing satire.
Now there are of course also people who do not understand radiocarbon dating. I do not think they will read the article that spoiled my day, but if they do, they will be left with the impression that the authenticity of the Turin Shroud is still contested. I am aware that our archaeologist intended to achieve the opposite, but he would have been more successful if he had said something like “that is not an issue anymore and it is a waste of time to discuss it – especially because I have something more interesting to tell”.
Because that is what is really sad about this article: our archaeologist has discovered something truly interesting. So you must read the story, after all, and try to ignore the crap. Good luck.
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Jona, many people also understand the importance of chain of custody in an evidence case, and the importance of contamination in radiocarbon dating; and some people are working on explaining to us how a linen cloth of unknown date, subjected to a raging fire in the late Middle Ages, might conceivably see its carbon isotopes screwed up thereby. Many people also understand that no one has been able to create a similar object today and that no reasonable mechanism for doing it in the Middle Ages has been shown (or at least had not until Prof. Garlaschelli’s team did?). So pending the resolution of all these uncertainties, yours truly will continue to believe, like a lot of reasonable people, that the object is a mystery. Not a Mystery mind you, but something not yet understood and certainly not yet dated.
So the article you link to — I guess: the link returns a message that the page “does not exist or is no longer available” — does add to the evidence against the putative 1c age of the shroud after all.
its carbon isotopes screwed up
Nope. If a piece of first-century cloth becomes so much contaminated by fourteenth-century soot that the laboratory dates it incorrectly, the amount of soot that has somehow penetrated the fibre must be very, very large. So large, in fact, that anyone would immediately recognize that the fibre was dirty.
Now I will be the first to admit that scientists can make errors that anyone with only the smallest bit of common sense might have avoided (the disastrous mirror of the Hubble space telescope comes to mind). Yet, accepting an extremely dirty piece of cloth is beyond stupidity, especially if we are to believe that three labs would have made the same mistake independently.
In fact, the three laboratories divided their pieces into three smaller pieces, which were cleaned in different ways. The results of the nine tests were pretty much identical, so the possibility of a cleaning error can be ruled out.
Cleaning surface soot is not the problem, if I understand the objection: but an actual interchange of the carbon molecules between the fibers and the other later stuff that burned in the late-medieval fire. My chemistry is of course not good enough, but I have to assume that theirs is whose theory this is, unless of course we’re having the linen pulled over our eyes.
The chain of custody is an altogether separate objection; the transfer of the cloth swatches from the shroud to the 3 investigating teams is documented (it was filmed) — except for a gap, something like the 18-minute gap in the Nixon tapes. That much is true; that there was a substitution during that gap thus becomes possible — or an exercise in sheer paranoia; but however that may be, the gap in the chain of custody allows doubt.
Moving off from the Shroud red herring, to your main point: the problem of writing for an unknown audience is one that anyone with a website faces, at least if the purpose of the site is to instruct. It’s a problem I’ve paid constant attention to over the years. Simply stated, people land on a webpage with very different baggage: from the top-level scholar who mines my site occasionally for some little tidbit easier got off the Web than digging in their library, to the young child with unclear ideas and maybe a misformulated search: and in the middle, adults with varying knowledge about a subject, and some of them more intelligent than me, others not. How to write text that speaks to all these constituencies, without talking down to anyone, without assuming knowledge or the lack of knowledge on the reader’s part, and without inviting merited criticism for over-simplification or tendentiousness or of course untruth.
The rule as usually stated is to write as if I were speaking personally to an otherwise educated person of my own level, who merely happens not to know anything about the particular topic. But your friend (who knew about Constantine from her nicely remembered history classes) could after all be legitimately irritated by such a standard treatment, yes.
One device I use from time to time, when something will be so well known to some, yet total terra incognita to others, is the litotes: a quick background of the topic, prefaced by some phrase like “The reader will probably not need to be reminded of…” or “It’s pointless to argue that…” or “Of course many of us will remember from our history classes…”. (One of the pages I find the best on my own site has to seek the shelter of such a litotes; but the device can’t be used more than very sparingly.)
There’s no way to please everybody, alas. Should I?