I agree with your first two sentences, but the rest of the conclusions
you draw from it only obtain if you assume a value-tree that is
static over time. To the extent that being "high" in the value tree
means actually exercising a lot of motivating force in determining
one's actions, then sometimes (particularly when one's life is
directly threatened) the fundamental value of being alive is going
to have a lot of motivating "force", and at other times it's going
to be a merely incidental background process. I think Minsky has
said somewhere that there is no such thing as "survival drive".
Perhaps there is no such thing naturally, but I suspect such things
can be developed, and perhaps it would be a good idea.
I also suspect that human cognition is far too plastic for us to
be able to discuss these things as if they were givens. That's
something that economists pretty much have to do (accept human
values as data) according to the traditions of their discipline,
but I like to think that we can do more than merely economic analysis
of ourselves.
Whether our values are linearly comparable or not, to the extent
that we can only do one thing at a time with our bodies, we hack
out some internal linear measure anyway... that's how we decide
what to do with our bodies at any given moment. This hacked-out
scalar approximation of "value" clearly changes from moment to
moment and differs from individual to individual; it may or may
not be derived from a more stable "deeper structure" which might
be modeled by some more complex data structure than a priority
queue. Furthermore, this hypothetical deeper structure may or may
not have perceivable elements that are "objective": products of
evolution that form a reliable (in the sense, I suppose, of living
a satisfying life and attaining reproductive success on both the
genetic and memetic levels???) "basis" for human values. But as
far as I'm concerned, all of this is merely metaphor, because none
of this is at the stage of measurement or prediction yet. It's not
even particularly precise.
As usual when discussing such things, I think it's important that
we not confuse our models of our values with our values themselves.
Our values are mysterious beasties in our brain somewhere; from a
different perspective, we could say our values are ourselves. There
are many possible perspectives on this stuff. But our theories
about values, our value-maps, our models are not the values
themselves. It has been my experience that forgetting this part
can lead to states that are too close to insanity for my taste,
which is why I like to bring it up whenever talking about this
stuff. Driving people insane is not (quite) my intention.
-- Eric Watt Forste ++ arkuat@pobox.com ++ http://www.pobox.com/~arkuat/