On Thu, 22 Feb 2001, Dan Minette wrote:
> I'll try to answer two at once here. If photons and electrons are things
> that exist apart from us, why don't they have positions between
> observations, and why are there time when they don't have fundamental
> properties, such as spin or polerization, before observation.
Super-super-nitpicky question: if science is only about what we observe,
how can we draw inferences about what happens to electrons between
observations? In other words, if what we know about electrons prevents us
from making inferences about their spin, position, and polarization
between observations, isn't there a leap of logic required to conclude
that they *don't* have any properties between observations? Another and
sort of stupid way of phrasing this question might be: if particles don't
have properties between observations, what does that imply for all our
theories about the state of the universe between the Big Bang and the
evolution of life?
Or, if "observations" really means "interactions (whether humans see them
or not)," do the particles' lack of defined properties between
interactions really matter, as long as we can understand the rules by
which they interact when they do so (i.e. as long as QM works)?
I guess the realist in me says, "If we can understand electrons well
enough to make predictions about how they will behave and would have
behaved billions of years ago, before humans even evolved, then we must be
pretty confident that they don't require human onservation to exist!"
> >1. Is realism, so defined, a metaphysical theory or an empirical/
> >physical generalization?
>
> It's metaphysical, as far as I see. Theories of science do not address the
> ontological status of what we observe.
It often seems to me, though, that you feel that QM does have implications
for the ontological status of objects. Or do I misunderstand you?
> If you expand your definition of
> realism to merely make it "there are things that really exist apart from our
> observations" then Plato was a realist. But, Plato is considered the poster
> child of idealism.
Yes, but Plato's brand of idealism doesn't imply (as far as I can recall)
that somebody has to observe things in order for them to exist--he's not
Bishop Berkley. His point is that the world we observe is a shadowy
reflection of something more real, more ideal (and, ironically, his brand
of idealism used to be called "realism," meaning that one believes that
ideals and concepts have a genuine and independent reality, as opposed to
the doctrine of nominalism, which supposes that ideas and concepts are
simply artifacts of thought and perception, i.e. names for things). But
that might be a little OT for this discussion....
> >If realism is truly a metaphysical theory, however, then one should be
> > able to understood it as eschewing from making statements or
> > predictiona about the structure of what we colloquially call the
> > physical world (hence *meta* physics).
>
> Actually the term metaphysics comes from Aristotle's book metaphysica, which
> was so named because it was the book after Physica.
Yeah, but the usage has evolved since then.
> Well, in general, that's true. But I'm not arguing for something as strong
> as confirmation or denial. I'm just pointing out that all four
> interpretations of QM, including the two realistic ones, have something that
> looks a lot more like nomenon that what realists have traditionally
> considered as the foundation of things.
But what? What definition of nomenon corresponds to that which we see in
QM? If I'm reading Kant correctly, science should never be able to
perceive, detect, or observe anything that "looks a lot like nomenon."
> Observations cannot confirm or deny metaphysics. But, some philosophies are
> routinely dismissed because they are hard to reconcile with how we live the
> world. For example, few idealists hold that what we perceive in this world
> has absolutely no connection to reality. Narcissism is not taken seriously
> in most philosophical circles.
Yes, and here's one of the tricky things about metaphysics...in order to
matter it has to have consequences (moral, intellectual...something) for
something in "the real world," however one chooses to define it, which
leads me to some thoughts on realism.
First of all, "realism" is a word so loaded with historical baggage that I
think it's important to know which flavor of it one wishes to refute.
My "gut-level" instict about realism is that it has to have something in
common with empiricism and skepticism; it seems to me that it would be
consistent with (some kinds of) realism to say that knowledge is
eminently possible but metaphysical certainty isn't. On the other hand, I
know that there are realists out there who go to great pains to try to
demonstrate that science provides us with some kind of metaphysical
certainty, and I'm skeptical about those theories too.
I have some quibbles with the definitions of realism that have been
offered up so far in this discussion. "Local Realism," it seems to me,
freights realism with a very specific and scientific definition of what
space and matter can be; so specific, in fact, that local realism ceases
to be a metaphysical statement and instead becomes a statement of
the classical assumptions of regular physics. I'm not convinced that
realism requires such assumptions.
Secondly, the definition of realism that you offered us at first, Dan--
"Realism is the philosophy that there is a real world, apart from our
existance and that we have direct access to that world via our senses.
Books, tables, chairs, electrons, stars, the universe all exist apart from
our observations."
--is problematic because of your inclusion of the word "electrons." By
equating electrons with chairs, you basically add to realism a version of
the physical theory of atomism, the notion that all matter is made up of
really tiny unreduceable particles which, aside from being really small
and more basic in structure, are really no different in quality from
chairs and tables. Again, realism ceases to be a metaphysical theory and
instead becomes a theory of classical physics, after a fashion, so of
course QM undermines it.
So the question that I'm putting to both of us is, is there a
metaphysical form of realism that doesn't commit itself to any particular
theory of physics? I think one of the issues for realism (and
empiricism, and especially skepticism) is that it's often a rejection or
negation of somebody's more idealistic metaphysics. There's a sense which
which realism and its sister philosohpies says "metaphysics is a waste of
my time, the only reason to engage in it is to discredit the outlandish
claims of other metaphysicians."
Personally, I'm not entirely sure that there can be a realism that doesn't
depend on empirical observation in some way. But I think that it is
possible to say without invoking any assumptions of physics that, 1) the
world exists independently of me but not I of it; 2) the world is
consistent in its laws; 3) I experience the world directly through the
senses; 4) because of 2 and 3, knowledge is possible (maybe not
omniscience, or metaphysical certainty, but knowledge). To me this feels
like making an inference from experience, so it might not qualify as
metaphysics. The metaphysics, such as it is, might come from evaluating
and rejecting such concepts of the nomenon and Platonic Forms as
unnecessary to explain experience and unsupported by evidence.
> Well, I tend to agree with Kant, but he wasn't a realist. Realists believe
> that we can gain understanding of reality through observations. If you
> read realists like Aristotle, Aquinas, early Wittgenstein, you will tend to
> get that feeling. Barkely and Hume were empiricists, and doubted the
> possibility of certain knowledge at all. They argued that even systems of
> mathematical understandings were based on empirical observations.
> So, if you think of it, all I am saying is that Kant was write in that the
> empirical is not the source of metaphysical cognition.
I'm not saying that Kant's a realist, just that his definition of
metaphysics implies that no theory of physics has the power to lend
support to his own metaphysics.
> > 2. How can any scientific discovery, if science is so defined, have any
> > consequences, for or against, any metaphysical theory, whether that theory
> > is realism or Kant's?
> >
>
> Well, that is a reasonable question. The best way to say this is that the
> strongest realistic philosophies tend to have general observable
> consequences. If you asked most realistic philosophers from the last 2000
> years if part of their metaphysics was that trees, rocks, oceans, etc.
> existed apart from humans, they would respond, (probably unanimously) with a
> loud yes.
And so far it's pretty hard to refute that theory, QM or no. :-)
Although: QM does suggest that by existing in the universe, humans are a
part of *everything* by means of the entanglement of particles. It just
doesn't imply that human observation is a prerequisite for everything else
to exist. Dead humans would be just as connected to the universe by
particle entanglement as live ones.
>
> > 3. Why does QM support the idea that the things we observe have a
> > noumenal aspect?
>
> Well, because its hard to match QM with a viewpoint that microscopic things
> that we observe are always where they are and what they are when we don't
> look. (By what they are, I mean having definite values for their observable
> properties.)
But how does does that consequence of QM bear any resemblance to the
noumenon? I could be remembering Kant totally incorrectly, but IIRC
Kant's theory is that all observable phenomena have an aspect, defined as
"noumenal," which *does* exist but can only be observed from a
transcendant point of view, i.e. by some kind of super-Pure Reason, a
viewpoint that has no physical or sensual intuitions or perceptions (i.e.
it's very much like God).
IOW, everything that humans observe is perfectly "real" for the purposes
of scientific investigation, but everything also has a transcendant aspect
that is also *more* real and which can only be apprehended directly by a
being with a similarly transcendant point of view, which humans aren't
privileged to have.
So, unless the argument is made that there is a transcendant point of view
from which the properties of electrons can be directly observed between
observations of wave-function collapse, I can't see how QM could possibly
relate to Kant's theory of the noumenon in any way whatsoever (which is a
totally different question from whether QM undermines some or all versions
of realism).
Marvin Long
Austin, Texas
