parsimony defined

[Cory Gross <GROS4891@Adc.MtRoyal.AB.CA>]

    G'day kiddies,
    
        I suceeded in finding A definition of parsmiony, though it 
isn't really specific to biology or palaeontology. Anyways, here it 
is, straight from _An Encyclopedia of Claims, Frauds, and Hoaxes of 
the Occult and Supernatural_ by James Randi (St. Martin's Press, ISBN 
0-312-10974-1)

            "'The law of Parcimony[sic], which forbids without
             necessity, the multiplication of entities, powers, 
             principles, or causes; above all, the postulation
             of an unknown force, where a known impotence can
             account for the effect.'[Sir W. Hamilton]
                (The rule was originally stated by Occam as,
             'Enitia Non Sunt Multiplicanda Preater Necessitatem')
                In effect, this rule states that if there exists
             two answers to a problem or a question, and if, for 
             one answer to be true, well-established laws of logic
             and science must be re-written, ignored, or suspended
             in order to allow it to be true, and for the other 
             answer to be true no such accommodation need be made,
             then the simpler-the second-of the two answers is much
             more likely to be correct."
             
        So thar' she blows mateys! I'll let you all argu-uh-debate 
over what the "proper" interpretion of this would be (ergo, who 
thinks they're right). All I can say is that in my interpretation, it 
takes more than _Sinosauropteryx_ to justify multiplying answers 
enough to make ALL dinosaurs feathered, or even all theropods. If 
that other potentially feathered bad boy pans out, then I'm only 
inclinded to conceed that at least real dromaeosaurids and not just 
Raptors[tm] were probably feathered. It'll take some better evidence 
than _Sinosauropteryx_ to back the extraordinary claim that all dinos 
had body fuzz. (And what makes it an extraordinary claim? The fact 
that we thought they didn't have 'em first. It ain't fair, but that's 
science <neener neener>:-)).

        Anyhoo, take care all...
        
        Cory

[ I really thought the question would have generated more responses...
  In any case, I prefer what the American Heritage Electronic
  dictionary tells me: "1. Unusual or excessive frugality;
  stinginess. or 2. Economy or simplicity of assumptions in logical
  formulation."  In a phylogenetic analysis, what you want to be
  stingy with is the number of evolutionary transformations required
  to produce the distribution of a given set of characters. -- MR ]


        "People are bloody ignorant apes!!" (who out there knows 
their plays:-))

*Cory Gross                          *  Ex ignorantia ad    *
*Secretary-MRC Earth Sciences Society*     sapientiam;      *
*Alberta Palaeontological Society    *      E luce ad       *
*gros4891@adc.mtroyal.ab.ca          *      tenebras.       *
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