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Re: orion 14C and falsifiability

 "Little reliance should be placed on an individual 14C date to 
 provide an estimate of age for a given object, structure, feature, or 
 stratigraphic unit.  A critical judgment of the ability of 14C data 
 to infer actual age can best be made with a suite of determinations . 
 . . Concordance of values on different sample types . . . from 
 well-defined stratigraphic contexts provides one of the strongest 
 arguments for the accuracy of age assessments based on 14C values" 
 (R. E. Taylor, _Radiocarbon Dating_, 1987, p. 105).
"The measurements performed in a radiocarbon age determination are 
 essentially those of experimental physics . . . Repetition of the 
 measurements will, in general, tend to produce a statistical spread 
 of results around the 'most probable' age . . ." (R. Switsur, in 
 _Radiocarbon_ 32, 1990, pp. 342-343)

 "Rejection of outliers is of course a thorny subject liable to 
 stimulate accusations that the data are being manipulated to fit 
 preconceived ideas. . . ." (M. J. Aitken, _Science-based Dating_, 
1990, p. 97)

Additional comments:
(1) Fred has no dating theory: I do.  
(2) I don't talk about Popper: Fred does.
(3) It is, unfortunately, slightly possible in any Cave 4 text case, 
not simply any one text in particular, that an individual radiocarbon 
date is contaminated to a slightly younger age than its true age if 
the sample dated had been exposed to castor oil.  The Zurich lab 
dated subsamples with different cleaning procedures and checked for 
differences: if the subsamples give different dates this is diagnostic 
of sample contamination.  Zurich reported none did except for TQahat.  
Therefore although this procedure is not infallible, Zurich's dates are 
less subject to this possibility.  The exposure of Cave 4 texts 
to scholars using castor oil in the Rockefeller Museum in the 1950's 
does not apply to the big Cave 1 texts (e.g. 1QIsaa, 1QS, 1QH, 
1QGenAp, and pHab).
(4) A brief perusal of the journal _Radiocarbon_ will show case after 
case after case of lab data presented on various archaeological 
dating projects in which contemporary items from the same context or 
date horizon are dated.  One gets used to a typically same pattern--many 
dates clustering around a "true" date, and a few dates that are off 
one way and off another way.  Those dates off at one end are not 
used to date the terminus, but on the other hand they are a pain in 
the neck!  A single Qumran text date out of 19 texts dated that has 
its two-sigma range in the 1st CE is not distinguishable in pattern 
from what 19 uncontaminated 14C date measurements would produce 
if all texts bore true dates in the 1st BCE.  (This is the distribution 
pattern that would be predicted, in such a case.  That does not prove 
that such a pattern of the texts' actual ages is true, however.)  
(5) Bowing to the turmoil my post on the 4QpPsa 14C date caused, I 
will change my wording if discussing this in the future:  I'll just call 
it a data point which is inconvenient to my theory, report it as such, 
acknowledge that if its true puts my theory out of business outright 
and, since the text in question portrays a contemporary, living 
Teacher of Righteousness, may also put Eisenman back into business in 
a big way.  :-)  
In the meantime, thanks to Sigrid and A. Lerner for their posts. 

p.s. T.S., cigarette or smoke particulates are unlikely to have 
contaminated scrolls 14C dates (or the Shroud of Turin 14C 
dates) because that is the kind of thing the acid-base-acid lab cleaning 
procedures are effective in taking out.  A second point is that 
sample contamination, when it is a factor, generally has small effects--
perhaps a century or two for a 1st CE item, rather than cutting an age 
in half, i.e. from 1st CE to medieval.  This is simple physics on the 
amount of contaminant in the carbon compared to the total quantity 
of carbon being measured.

Greg Doudna