"jem" <xxx@xxx.xxx> wrote in message news:YSGLe.252$_F1.31@lakeread04...
> Autymn D. C. wrote:
>> jem wrote:
>>
>>>:)  I see.  You plan to correct posters for not writing as they think,
>>>and you'll determine how they think based on what they write.  Logic's
>>>not one of your stong suits, is it?
>>
>>
>> It is, and it isn't yours.  "as they think" and "think based on" are
>> equivalent to p -> q !=> q -> p.  Scientists calibrate carbon dating by
>> tree rings, and calibrate tree rings by dating.

They calibrated the rings by matching the
rings near the beginning of one tree's
record to those at the end of an older
tree to produce a continuous record of
overlapping samples.

>> Does that make their
>> study a bunch of rubbish?  ...

Not when you know what was actually done.

George