[From Bill Powers (960912.0600 MDT)]
Rick Marken (960911.2150)--
Biologists have been able to figure out the purposes
(functions) of so many biological structures for
the same reason that psycholgists have been able
to figure out the causes of so many behaviors:
because so many people have been willing to
believe Nobel laureates and other important
sounding trendy types who study biological functions as
though they had purposes (functions) and who study
behavior as though it had causes.
What a beautiful paragraph. It sums up all the reasons for which PCT is
rejected by conventional science.
It's not just biology that does this -- how about paleontology and
anthropology? Bruce Abbott mentioned figuring out the purposes of artifacts
from studying their functions. But how do you do this? You try to guess how
the person who made the artifact might have used it. You pick up the flint
core and try pressing or hitting it with a bone, and discover that flakes of
flint with sharp edges come off it. But so what? Then you find that you can
use the sharp edges to cut softer things. But so what? Then it occurs to you
that you could make clothes out of hides if you could cut holes in the hides
-- ahah! The purpose of the flint core and the bone is to cause people to
wear clothes!
When you study an artifact, you're trying to guess what purpose a human
being might have had in making it. The problem is that you can never know
for sure that you're not inventing a use that the person who made the
artifact never even thought of. The Incans (or was it the Mayans) invented
the wheel, but it was used only for toys, not for transporting goods or
people. Someone who didn't know that, and who lived in a civilization with
carts and automobiles, could easily assume that finding a wheel meant
finding a civilization based on serious uses of the wheel.
Anyway, the properties of an artifact are inextricably intertwined with the
goals of the person who made it. No matter what functions a given artifact
might be able to perform, it can't perform them unless it is used in a
particular way, and it will be used in that way only if the consequence of
doing so matches some consequence that the person wants to experience. A
worn stone and a pestle may once have "had the purpose" of grinding grain.
But nobody who wants to have teeth 20 years down the line would use it for
that purpose now.
At Mesa Verde, where Mary and I will be going again during a two-day trip
starting today, there is an expanse of slickrock perhaps 10 meters in
diameter, in the midst of a scrub-oak, pine, and juniper forest on the
plateau. In the middle of it is a clearly artificial cylindrical hole about
four or five inches in diameter and two or three inches deep. The park
ranger ask a group of visitors what they thought its purpose was. After the
visitors had offered their guesses -- a sipapu, a socket for a flagpole, a
grinding-pit -- someone said "I give up -- what WAS its purpose?" The ranger
answered, "Nobody knows. We always ask because maybe someone will come up
with a good guess."
This bit of humility went over well in the group we were with.
Of course sometimes we come up with very reasonable guesses about artifacts.
A thin-walled concave object very likely was used to hold things like nuts
and berries or grain. If we think it's waterproof, or was when it was used,
we might reasonably guess that it was used to hold water or something wet
like mush or milk. If it has a cover, we might guess that it was used to
store something edible. Why? Because we can see that the bowl could be used
that way: that's what WE would do with it. We don't HAVE to use it that way,
but if we want to store things or hold things to eat, and most people do
this, the bowl provides a simple way to do it and that's probably why it was
made. But implicit in every use is a human goal or intention; when we infer
a function, we are really inferring what some person wanted. We're simply
imagining ourselves in the place of the maker or user, and asking "What
would _I_ do with this thing?" And who is to say that we're guessing right?
The object itself is mute; by itself, it has only properties, not purposes.
Speaking of objects as if they had purposes apart from the way they are used
reflects a general confusion in science -- even in nice, smart, Nobel
laureates -- about how organisms work. And this confusion shades into a
confusion about how even non-living matter works.
Best to all
See you in two days
Bill P.