Re: Rigid Properties
Nicola et al.,
The distinction between rigid and non-rigid is one aspect of the triad
that Peirce (and I) have been trying to get across (with limited success)
for many years. The various problems that have been discussed in the
"rigid properties" thread illustrate how important and all-pervasive
that triad is.
During the Heidelberg meeting, Husserl's distinction of dependent vs.
independent was accepted by everyone as an important distinction, but
I kept insisting that it represented only the first two parts of a triad.
Some people suggested that the third part might be defined as "dependent
on more than one other", but that trivializes the third to the point
where it has lost the most significant aspect: mediation between the
others.
Peirce introduced a fundamental distinction between the ontological
categories and the phenomenological categories. An ontological
category arises from the attempt to classify something as it is
by itself independent of any observer. A phenomenological category
arises from the attempt to classify something as it appears to
some mind (human, animal, robot, plant, or even bacterium).
The example of a hammer illustrates the point: a rock is a naturally
occurring entity that can be described ontologically by its matter
and form. It can be described phenomemologically by the way it is
perceived: how it looks, what use it can serve the viewer, and what
it can tell the viewer -- about its origin, its previous use by humans
as a hammer or by insects as a shelter, and its effects on the environment
by scraping a tree, deflecting the pathway for deer and hikers, or
providing a hiding place for creepy crawly things.
The distinction between naturally occurring vs. human artifacts is another
sometimes helpful, but more often confusing distinction. A rock doesn't
lose its ontological status as a rock by how it may be used or perceived.
And there is nothing fundamentally different between being used by a
human or by an ant or even a bacterium. Our provincial, species-related
preferences may be the first things we think about and talk about, but
there is no fundamental difference between a human house and a beaver
dam or a termite mound. And once you allow beavers or termites to
have the status of "artifact makers", you can't rule out plants
that form mangrove swamps or single cells that "decide to" or are
somehow "induced to" form slime molds.
Nicola wrote
>By the way, better talking of "properties" rather than "classes". A
>property can correspond to multiple classes (its extensions) in
>different worlds/situations. This is related to the modality
>discussion, however (different thread).
I agree. Nominalists try to avoid talking about any kind of universals,
but they sometimes admit sets or classes as the least objectionable
kinds of abstract entities. However, once you admit enough ontology
to build up mathematics, you have all the shapes, forms, and patterns
of any kinds of universals anyone has ever dreamed about. I admit all
of mathematics into my ontology, and that provides plenty of predicates
(properties, relations, types).
>Indeed all examples with artifacts are tricky. I agree that in many
>cases is useful to take the intended role as an essential property of
>artifacts. So we may postulate a difference between a stone
>intentionally shaped to be used as a hammer and a stone that
>accidentally has that shape. Saying that "hammer" is rigid means that
>no accidental hammer exists.
The "trickiness" of artifacts indicates that the rigid/nonrigid
distinction is too limited. I don't postulate any difference,
ontologically, between a stone used in any way. But there is,
of course, a big difference phenomenologically. However, that
same difference applies to everything. Everything we encounter
has aspects of quality, reaction, and mediation -- Peirce's three
phenomenological categories. There are no accidental beaver dams,
termite mounds, mangrove swamps, or even rocks.
>In the case of the bomb, I agree that it is essentially intended to
>blow things up, but in my example I imagined that something that
>blows things up may not be essentially a weapon: so "being a bomb"
>may be a rigid property, and "being a weapon" a non-rigid one...
>Another example is a knife: it may be a weapon, it may not (while
>remaining essentially a knife).
The word "essentially" in this context simply means "its current
form is the result of...." But every object has a form that results
from its previous history. We could replace the word "artifact"
by the phrase "shaped by human intention", which we could generalize
to "shaped by the intention of species X". But then the crucial term
to be explained is "intention", which is one aspect of Peirce's
mediation.
>These reflect only particular points of view, of course. The
>important thing is that these points of view can be clarified by
>using the rigid/non-rigid distinction.
The most important thing to clarify is the phrase "points of view".
That is precisely what Peirce was doing with his phenomenological
categories.
John
:wq