Thanks, Rich:
I just HAVE to answer this one thing... (the rest seems either not too important and/or we're largely in agreement).
On 11/2/2010 9:10 PM, Richard Pyle wrote:
on the following grounds. The basic model of reference in play is (crudely): uses of human language<==> some sort of mapping/reference<==> entities in nature.
I guess I need to understand what you mean by "entities". Is a taxon an entity in nature (existinting independantly of a human's definition of it), in your view? If so, we may be stuck on first principles, at which point the safest thing to do (for all parties involved) is to agree to disagree.
I'm also struggling to understand the scope of "uses of human language". Are we talking just taxon name-labels? Or do you also include the way we refer to diagnostic characters and such?
The whole point of the taxon concept approach - done right in my (not really all that humble) opinion - is that the question about reality, versus construct, versus some mix thereof, is not really relevant. Wrong question, so to speak. A solid taxonomic concept approach should be able to accommodate taxonomic practice as it is actually being done.
If all taxonomists thought that their perceptions of taxa (including feature diagnoses) map to something "objectively" real (independently of the particularities of human cognitive abilities and semantic conventions => "the causal structure of the world") - fine, then the a well executed taxon concept approach shouldn't have a problem with that.
If, on the other hand, taxonomists thought of their products merely as a matter of quasi-reliable and convenient vocabularies that somehow reflect something about the human-external world but could well be very different and still serve their purpose ("arbitrary constructs" - though it's never that arbitrary once you start down a given path and test for reliability) - then just the same that should be accommodated within a taxon concept approach.
So then, the reason why mentions of PhyloCode-like definitions of clades vis-a-vis concept taxonomy tend to give me light allergies, is because phylogenetic taxonomy actually does on occasion make fairly strong claims about what nature is like, and how good taxonomic practice should reflect this ("use definition type X, not Y"). In that sense, I regard concept taxonomy as a full-fledged alternative and competitor to PhyloCode-like taxonomy. Both, I think, try to improve upon the semantics of Linnaean taxonomy and ultimately help users. But the PhyloCode, if I am allowed the strong oversimplification, tries to do so by getting definitions of taxa right once and for all. Concept taxonomy, on the other hand, is exclusively interested in comparing and reconciling different taxonomic "products" (concepts, classifications) published at different times and likely under different systematic paradigms. The issue is not at all whether we got the concepts "right", i.e. whether they closely map to natural taxa. Instead, the goal is to properly archive the sequence of views (so that ontological reasoning may come into play). Normative claims about practice are restricted to the practice of archiving only.
I think taxonomic publications are real (enough), and I think occurrences of intersubjective human understanding and misunderstanding are real (enough). That's what concept taxonomy should concentrate on representing. The rest is up to the producers and users.
Respectfully,
Nico