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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)
(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.