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orion Dating of scrolls (long)




Sigrid Peterson writes:

> evidence in an exhaustive way. That would involve, for example, going through
> all of the published DSS volumes and recording, tabulating, the paleographical
> judgments of the assigned editor of each ms. That would be a wonderful service,
> and if more than 50% of the ms were dated outside your Generation by independent
> judgments of editors, your hypothesis would be falsified. Since that evidence
> now exists, if you don't report it, you are only arguing, not using data. 

I am sorry--I flat out don't accept palaeographical date estimates 
published in DJD volumes as data.  Those are guesses and based on 
argument from authority.  Radiocarbon measurements are data and 
these are not the same animals.  With radiocarbon data there is 
no argument from authority component (except in the interpretation 
of the numbers).  With the Cross-based paleographic date estimates 
there are are no numbers independent of argument from authority. 

Without accepting the palaeographic date estimates as data, let me 
say about two-thirds of them are probably right.  Two-thirds of them 
are already in the 1st BCE--those ones are probably right.  Its like 
the broken clock that is right twice a day, except in this case the 
percentage is higher.  The palaeographic date estimates older than 
1st BCE may be right too.  Only the 1st CE palaeographic dates are at 
issue, and since these date guesses were created in a vacuum of 
dated exemplars in the centuries at issue for the formal scripts at 
issue, published 1st CE palaeographic date estimates are entirely 
original intuitions that have become argument from authority. 

> probability falls off symmetrically from the top of the bell curve. Therefore,
> the highest probability date for 4QpPs(a), by carbon 14 dating, is 58 CE. That
> is the halfway point between the two dates 5 and 111 CE. The probability that
> the true date is between 48 BCE and 5 CE is about 11%. The probability that the
> true date lies between 101 BCE and 48 BCE is about 5%.

This is simply not correct Sigrid.  There is no systemic higher 
probability in the middle, because the calibration curve is 
nonlinear.  You are confusing a linear, Gaussian bell-curve which you 
learned in your statistics classes with this.  This is hard for the 
radiocarbon field to explain to the public.  Let me give an example.  
Tucson dated three economic texts whose true dates are Bar Kochba, c. 
130 CE.  It happens that there is a steep drop in the calibration 
curve from 125 to 135 CE, and then a flat stretch after that more or 
less for one to two centuries.  ANY text with a true date of 135 CE is 
going to get a two-sigma range that extends no earlier than about 130 
CE but will extend about one or two centuries into the 2nd and 3rd CE.  
ANY texts with a true date anywhere in that 1-2 centuries range 
are going to show the SAME calibration calendar date range.  The highest 
probability is not in the middle!--not for radiocarbon dates.  That is a fallacy.  
The highest probability is the entire range, versus outside the range, 
which is low probability. 

On your criticisms of my treatment of 4QpPs(a), to be specific, I do 
not claim it is false, only that I have reason independent of any scrolls 
dating theory to question that it is true.  Let us stipulate it is unlikely 
the pPs radiocarbon date is the tail end of a bell curve (i.e. one of the 1/20 
cases in which true dates are going to be outside of two-sigma carbon 
dates).  It is either a contaminated date or a true date.  There was a 
2nd CE date on 4QS(d) that is known contaminated, at one far end, 
and there is TestQahat at Zurich which is a suspected (though not known) 
contaminated date at the opposite far early end.  pPs(a) is the younger 
end of the remaining dates.  With the 4QS(d) 2nd CE date both the lab 
and the scrolls persons did what you say is the wrong thing to do, but 
which was the right thing to do, and said, "This is out at one end and is 
unusual--we are skeptical.  Let us redate this and find out what is going on".  
Another sample was cut and dated, and its different dating, of the 
same text, confirmed suspicions that there had been a contamination 
problem.  No similar recheck was done with pPsa, the next youngest 
date.  Yet its measurement does not agree with pHab, and it is 
younger than all other Qumran text dates.  These text radiocarbon dates 
cannot be viewed in isolation, atomistically, as if there is some 
kind of inerrancy or equal weight to any data point.  These dates must 
be interpreted in the light of being in an archaeological assemblage with 
each other.  It is the old problem of outliers in data--what is an outlier, 
how does one interpret it, what does one do with it.  No doubt with 
further data there will be more odd dates, not many, a little early and 
a little later than anyone expects.  One can't simply take these dates
at the ends at face value (few in the Qumran field do take the TQahat 
14C at face value).  More data will solve this by giving a context to 
know whether the pPs date is an outlier or routine.  Since that 
information, that context, does not exist in present radiocarbon 
data, it gets neither affirmation or denial--from me, that is.

There is an unfortunate thing with these scrolls.  The early 
team--Cross, Allegro, etc--were dousing these things in castor oil to 
clean them.  They didn't know any better.  But none of the cleaning 
procedures used at Zurich or Tucson (I have checked this with 
chemists) would have taken out castor oil, if it was there.  It would be 
undetected, and would give an anomalously younger (not older) 
radiocarbon date.  There are some solutions to this which I won't go 
into here, but in principle a way must be found to test for the 
presence of castor oil (and not date samples which have it).  In the 
meantime we hope that samples dated happen to have been 
ones that weren't affected.  The fact that most of the 14C 
dates have independently converged on 1st BCE is a strong 
argument that contamination is not affecting most scrolls dates.  
These problems are not insoluble, but there is trial and error in 
this.  But the only way forward is forward--learn from previous 
batteries and do it better the next time around.  But that's the way 
science works. 

Contamination is unfortunate, I don't think it is a significant 
factor in most of the 14C dates, but it is a dragon which must 
be fought.  Either to assume or deny the radiocarbon date for 
4QpPs(a), which is out at one end, at this point is foolish.  This 
has nothing to do with a dating theory, but is the objective fact 
that it is out at one end of the existing radiocarbon data--that is 
objective.

> I don't see how this is a data-based analysis according to principles advocated
> by Popper, unless there is something you are doing but not telling, such as the
> tabulation of all the paleographical datings of mss.

Someday I hope there will be reliably based palaeographic datings to 
tabulate. 

> similar properties. If there are enough problems with the carbon-14 test that it
> doesn't give results that are reliable, then you don't use it at all, in the

No, no, no.  It isn't all or nothing, the same with any archaeology.  
This is the same argument creationists use to disprove the theory of 
evolution, i.e. show a scientist made and corrected a mistake at some 
point in the past.  Radiocarbon dating is proven in principle, the 
best of the modern labs know what they are doing, and it is a 
technical issue to beat the contamination spectre with the scrolls.  
   
Greg Doudna
Copenhagen