HON 280 -- LECTURE FOUR (PLATO)
THE DEVELOPMENT OF SCIENCE
As we noted last time, the first systematic philosopher with the
first systematic theory ff nature was Plato (born 427 BCE).
From Athens, a wealthy aristocratic family. Originated western
philosophy, especially western political philosophy. Great story
-- Syracuse. Dionysius I, II.
I. As we also noted last time, he has a peculiar deflationary
attitude toward the natural world.
A. He denigrated it. That is, he didn't think that it was the
highest object of study because it didn't have the highest
possible level of existence.
B. We illustrated this by recalling the allegory of the cave.
1. What is the horse shadow: Probably a visual
impression of a horse? Real
2. What is the horse puppet? A horse. Really real.
3. What is the horse running around on the surface of
the earth? The Form of horse. The really really real.
C. The idea is this: Concrete objects have less reality than
the forms of which they are implementations or in which
they participate. Why? Because the forms make concrete
instances intelligible in a way in which concrete instances
don't make the forms intelligible. More abstract things
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make possible the existence of concrete things in a way that
doesn't work the other way around. And this is what makes
them more real.
D. Thus, true knowledge, for Plato, was a movement from
the concrete to the abstract.
II. How can we think about this in a way that keeps it from
sounding too mystical?
A. Think about the relation between the shadow and the
puppet. The puppet explains why the shadow exists; it
makes the occurrence of the shadow explicable or
intelligible to us.
Let's think more about this "making intelligible" relation.
What is it supposed to be? Perhaps it's pretty clear in the
case of the puppet/shadow case. What is it here?
B. What is it in the case of the horse/form of horse case?
Not causal, right? Let's look at some of the examples that
Plato cites in which he tries to explain what it is.
1. One occurs in a Platonic dialogue called the
Symposium (210a-211b) in which Plato describes a
party involving Socrates and a bunch of his drunken
pinhead friends. In this dialogue, Socrates is trying to
figure out the nature of beauty. This may seem odd,
that beauty has a nature as horses have a nature, but it
didn't seem odd at the time.
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2. Here Plato talks about the Ladder of Love. The
Love Ladder, Something for the ladies. And I say this
tongue in cheek. Because of Diotoma. There is thus
textual evidence that the fundamental investigative
methods of western philosophy came from a woman,
not Socrates, whom we nothing about.
3. Anyway, here a "lover" is defined as someone who
loves and "loving" is defined as a desiring for
something that one does not have. He describes the
following progression as one proceeds up the ladder of
love in search for beauty in its most direct form.
(a) beautiful body.
(b) All beautiful bodies. Lover of everybody.
(c) Beautiful souls. The "lover of everybody"
must "bring his passion for the one into due
proportion by deeming it of little or of no
importance." Instead, the passion is transferred
to a more appropriate object: the soul.
(d) The beauty of laws and institutions - The
next logical step is for the lover to love all
beautiful souls and then to transfer that love to
that which is responsible for their existence: a
moderate, harmonious and just social order.
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(e) The beauty of knowledge - Once
proceeding down this path, the lover will
naturally long for that which produces and
makes intelligible good social institutions:
knowledge.
(f) Beauty itself - This is the platonic "form" of
beauty itself. It is not a particular thing that is
beautiful, but is instead the essence of beauty.
Plato describes this level of love as a
"wondrous vision," an "everlasting loveliness
which neither comes nor ages, which neither
flowers nor fades." It is eternal and isn't
"anything that is of the flesh" nor "words" nor
"knowledge" but consists "of itself and by
itself in an eternal oneness, while every lovely
thing partakes of it."
(g) Even above this is the form of the Good.
The form of beauty is itself a good to the
extent that it participates in the form of the
good. The form of the good, we may say, is
really, really, really real. (What could be
clearer than this?)
4. Anyway: The idea is that knowledge concerning
other things is similarly gained by progressing from a
base physical instance of the thing sought to the
eventual form of the thing sought. One then has
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knowledge of the thing by having familiarity with its
defining essence.
5. So, in connection with natural science, what you
have to understand first about Plato is that he doesn't
credit it with much importance. There isn't much to
know about it because it really isn't an object of
knowledge. It doesn't have as much reality as the
forms that it implements or instantiates.
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some importance. He has a cosmogony and a
cosmology. The cosmogony (in the Timeas) involves a
demiurge who imposes order on the chaos.
(a) Because he is divine, he tries to order the
world as intelligibly as possible, but the way
this works is that he imposes an order on
nature which then continues to operate more
or less on its own without divine
intervention. But mind is still present in
nature to the extent that that it encodes the
original intention.
(b) As for Plato's physics, he assumed with
everyone else that there are four basic
elements: earth, water, air, and fire, and then
associated these elements with different
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geometrical solids, and then tried to
understand compounds as the result of the
combined component triangles of these
solids. That last aspect is one of which I
have never been able to make much sense.
It's more mystical than scientific. But at
least he is trying to give an account of nature
in quantitative terms.
III. Most of what he had to say of any importance about the
natural world is astronomical. He and his students
(Eudoxus 400 BCE) tried to account for long-known
astronomical facts. e.g., the retrograde motions of the
planets (especially Mars) and various uneven motions of
the sun and the moon with the following model. You can
find a great visual explanation of what retrograde motion is
at http://alpha.lasalle.edu/~smithsc/Astronomy/retrograd.html.
It is a system of spheres moving within spheres which are
themselves moving in different directions, to create complicated
messes like that below (for the moon):
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