On Jul 19, 2011, at 8:26 AM, Richard Pyle deepreef@bishopmuseum.org wrote:
Well, plenty of things are not in the class (Localities, dates, etc., etc.).
If we agree (do we?) that the class we seek to define is a subclass of biological entity, then I would assume that localities, dates, etc are already excluded. Hence, we only need to look at things that are biological entities, but that are to be excluded from the class (presumably because they are members of other disjoint sibling subclasses of biological entity).
But more specifically, I would say that any circumscription of organisms that is based on an intensional definition (sensu Régine) would be excluded (and would instead be covered by the "Taxon" class). That is, if a set of organisms is defined by properties, rather than by specific members, it would be excluded from this class.
A set defined by shared properties of its members is a class, not an instance.
Also excluded from this class would be an organism or set of organisms bounded by time or space. What I mean by this is that the temporal scope of an organism instance begins when the organism(s) is/are born, and ends when the organism(s) disintegrates
I'm confused by what exactly you mean by intensional definition. Above you say it is a circumscription of organisms, which isn't a biological entity (a circumscription of an organism is not an organism), and thus already excluded. But an organism bounded by space and time is an organism, and thus would be included if we include all organisms (but perhaps we don't?).
Maybe it's just me though - Bob seems to understand what you mean.
Also, one cannot define an instance of organism dynamically via space and time, such as "all whales off Maui during the winter months", as the members would change year after year.
This is a definition for a class (a set of instances) rather than giving examples of instances. We need the latter.
-hilmar
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