[Taxacom] More evidence turtles are diapsids

[Richard Zander]

Interesting exchange here. 
 
>From a non-philosopher-of-science viewpoint, you got yer theories, you got yer hypotheses and you got yer facts. Theories seem somewhere in the middle of hypotheses and facts, and are apparently hypotheses strongly supported by facts (which themselves are well-documented observations, or, Fitzhughianly, deductions from such facts), such that a scientist might act on them with some confidence (Bayesianly).
 
So we want 
 
- hypotheses, generated by blue skys and soaring imagination with one foot on the ground, 
- plus facts, 
- plus deductions from facts (deductions from facts and even first principles must logically always be true, right?), 
- plus theories, 
 
to make science work. Apparently how to keep all these separate, and the misuse of one because another is appropriate, is the contention in this thread.
 
Note that in hard sciences (nomological deductive), theory is important, while in systematics (historical explanatory) we often (must) settle for hypotheses. I think the hyperprecise results of cladistics are founded on faulty evolutionary theory (see the "modern evolutionary systematics" Web site for revealing info you can't do without), and those now on the cutting edge of research in systematics have gone from tongue-in-cheek hypotheses to a craps shoot. The only fairly sure results of evolutionary theory in systematics are the "natural" families generated back in the glory-age of systematics, the mid-1900s. 
 
_______________________
Richard H. Zander
Missouri Botanical Garden
PO Box 299
St. Louis, MO 63166 U.S.A.
richard.zander at mobot.org
 

________________________________

From: taxacom-bounces at mailman.nhm.ku.edu on behalf of J. Kirk Fitzhugh
Sent: Fri 10/16/2009 12:53 PM
To: taxacom at mailman.nhm.ku.edu
Subject: Re: [Taxacom] More evidence turtles are diapsids



Nothing that you just said has any relation to formal logic. The
formation of a hypothesis is by way of non-deductive inference, thus is
irrelevant to 'test validity' since testing involves a different set of
inferential actions. No causal claims are required or desired in
hypotheses? Wow, no more need for me to discuss this subject with you.

Thanks for the illuminating, if not terrifying interpretation of how to
(not) do science.

Kirk

mivie at montana.edu wrote:
> You don't understand formal logic.  A hypothesis stands alone, and  is
> valid if it can be refuted.  Period.  The specific formation of the formal
> hypothesis is what determines the test validity.  As stated in the one
> presented, there are no causal issues involved (a nod to the pattern
> cladists), so there are no "causal claims in the hypothesis" nor is  one
> required (nor even desirable) in a valid hypothesis. The hyp stated does
> not require consequences to be valid, but may be used to construct further
> hypotheses (or not). Deductive consequences are themselves just-so-stories
> until tested as hypotheses. The hypothesis is based on discovery of new
> characters, so is not dependent on previously used characters -- your
> "vague causal conditions pertaining to the characters from which the
> hypothesis was inferred" do not appear in the hypothesis at all.  The
> narrower the hypothesis is the better it is formed.
>
> Mike
>
>
>  
>> These aren't deductive consequences, thus not test evidence. New
>>    
> characters can't be deduced from a phylogenetic hypothesis, since the
> hypothesis only states vague causal conditions pertaining to the
> characters from which the hypothesis was inferred. What is in need of
> being tested are those causal claims in the hypothesis, thus we have to
> find evidence that those occurred. This has been a long-standing
> misunderstanding in cladistics for far too long, and has been maintained
> in recent years by some authors publishing papers (especially in
> /Cladistics/), where the basic rules of deduction are blatantly
> violated.
>  
>> Kirk