Map and Territory

[From Rick Marken (960912.1445)]

Hans Blom (960912) --

wet-bulb temperature and dry-bulb temperature are measurements obtained
with suitable sensors under appropriate conditions. "Dewpoint and relative
humidity can be determined from the wet bulb [temperature] depression using
a psychrometric table." So dewpoint and relative humidity are measurement-
derived abstract concepts that are part of our scientific theories.

Dewpoint and relative humidity are measurements that are functionally
dependent on other measurements (wet-bulb and dry-bulb temperature); in PCT
dewpoint and relative humidity are higher level perceptual variables
because they are necessarily derived from lower level perceptions (wet-bulb
and dry-bulb temperature). Similarly, the perception of the area of a
rectangle is a higher level perceptual variable that is derived from
lower level perceptions of length and width . The formula that relates
dewpoint to wet and dry bulb temperature is probably a lot more complicated
than the simple multiplication that gives area from length and width; but
it's the same idea.

Perceptions, like those of dewpoint and relative humidity, can be part of
still higher level perceptions, like the perception of a scientific theory,
but that is not necessarily true. A system can still be designed to perceive
dewpoint and relative humidity even if that system has no ability to perceive
any scientific theory.

Do they (also) have an "independent existence in the environment"? How about
force, acceleration, mass?

That's the $64 dollar epistimological question, now, isn't it? I'm quite sure
we will never know the answer. All we will know is that some ways of
perceiving the world (like in terms of forces, masses and accelerations)
better serves certain higher level purposes (like the purpose of launching
satellites) than other ways of perceiving the world. Of course, if Fred
Nickols is correct and there is no such thing as purpose, well, then we
won't care about it,one way or the other;-)

Best

Rick