Transcript Ancient Greek Metaphysics

Ancient Greek Metaphysics
Particulars
Particulars: can’t have multiple instances
Dan Bonevac, Gavrilo Princip
Empire State Building, Perry-Castañeda
Library, that beach ball, this grain of sand
Austin, Texas, Sarajevo
November 11, 1918
The assassination of Archduke Francis
Ferdinand
Universals
• Universals: can have multiple instances
– Properties: red, triangular, large
– Relations: between, on, love, friendship
– Kinds: tiger, building, pencil, shortstop
– Books: the Bible; Edwin Mullhouse
– Musical works: Luckenbach, Texas; Bach’s
Toccata and Fugue in D Minor
Are Universals Real?
• Realism: yes, and mind-independent
• Conceptualism: yes, but mind-dependent
• Nominalism: no— everything is particular
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• Real
• Unreal
Mind-dependent
Conceptualism
Nominalism
Mind-independent
Realism
Why Think Forms Exist at All?
• Necessary for knowledge
• Without forms, we could
– Perceive
– Generalize
• But we couldn’t
– Understand why things happen
– Know any universal or necessary generalizations, as in
science, mathematics, or philosophy
• There must be something all Fs have in common, by
virtue of which they are Fs
Plato’s Enemies: Parmenides
• Parmenides holds that change is
impossible
• Say that a thing changes:
• a is F at time t, but not F at t’
• But then a is both F and not F
• That’s a contradiction
• So, nothing changes
Plato’s Enemies: Heraclitus
• That doesn’t show that change is
impossible
• It just shows that objects don’t persist
through change
• There are changes: one object
succeeds another
• “You can’t step into the same river
twice.”
Plato’s Enemies: Sophists
• The Sophists are relativists
• “Man is the measure of all things”
• What’s true for me might not be true for
you
• Meaning might be relative too
• So, maybe you don’t mean by your words
what I mean
• Maybe my meaning changes over time
Plato’s Enemies: Skeptics
• The Skeptics deny the possibility of
knowledge
• There is such a thing as truth
• We just can’t get access to it
• How is it possible for us to
communicate? I can’t know what you
mean (or even what I meant)
Forms Explain How We Can
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Think general thoughts
Account for regularities
Account for change
Think the same thought at different times
Think the same thought as each other
Think veridical thoughts
Plato’s Divided Line
• “You have to imagine, then, that there are two ruling
powers, and that one of them is set over the intellectual
world, the other over the visible. . . . Now take a line which
has been cut into two unequal parts, and divide each of
them again in the same proportion, and suppose the two
main divisions to answer, one to the visible and the other
to the intelligible, and then compare the subdivisions in
respect of their clearness and want of clearness, and you
will find that the first section in the sphere of the visible
consists of images. And by images I mean, in the first
place, shadows, and in the second place, reflections in
water and in solid, smooth and polished bodies and the
like. . . .”
Plato’s Divided Line
• “Imagine, now, the other section, of which this is
only the resemblance, to include the animals
which we see, and everything that grows or is
made.”
The Divided Line
• Visible World
Intellectual World
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• Shadows,
• reflections
Objects Mathematical
of perception forms
• Perceptions of
• shadows, etc.
Opinion Understanding Reason
Abstract
forms
• Visible world is like a reflection of the intellectual world
The Cave Allegory
• “And now, I said, let me show in a figure how far our nature is
enlightened or unenlightened: -- Behold! human beings living in
a underground den, which has a mouth open towards the light
and reaching all along the den; here they have been from their
childhood, and have their legs and necks chained so that they
cannot move, and can only see before them, being prevented
by the chains from turning round their heads. Above and behind
them a fire is blazing at a distance, and between the fire and
the prisoners there is a raised way; and you will see, if you look,
a low wall built along the way, like the screen which marionette
players have in front of them, over which they show the
puppets.”
The Cave Allegory
• “And do you see, I said, men passing along the wall carrying all sorts of
vessels, and statues and figures of animals made of wood and stone and
various materials, which appear over the wall? Some of them are talking,
others silent.
• You have shown me a strange image, and they are strange prisoners.
• Like ourselves, I replied; and they see only their own shadows, or the
shadows of one another, which the fire throws on the opposite wall of the
cave?
• True, he said; how could they see anything but the shadows if they were
never allowed to move their heads?
• And of the objects which are being carried in like manner they would only
see the shadows?
• Yes, he said.”
The Cave Allegory
• “And if they were able to converse with one
another, would they not suppose that they
were naming what was actually before
them?
• Very true.
• And suppose further that the prison had an
echo which came from the other side, would
they not be sure to fancy when one of the
passers-by spoke that the voice which they
heard came from the passing shadow?
• No question, he replied.
• To them, I said, the truth would be literally
nothing but the shadows of the images.”
The Cave Allegory
• Philosophy tries to turn people away from shadows. It
tries to make people see the true nature of the world- to get beyond appearances to realities
• The prisoner released from the cave will be able to
see reflections, then objects, then the moon and
stars, and finally, the sun
• The progression: the divided line— from reflections to
objects to mathematical forms that reflect the most
abstract forms; finally to abstract forms themselves
Meaning of the Allegory
• “This entire allegory, I said, you may now append,
dear Glaucon, to the previous argument; the prisonhouse is the world of sight, the light of the fire is the
sun, and you will not misapprehend me if you interpret
the journey upwards to be the ascent of the soul into
the intellectual world according to my poor belief,
which, at your desire, I have expressed- whether
rightly or wrongly God knows.”
The Good
• “But, whether true or false, my opinion is that in the
world of knowledge the idea of good appears last of
all, and is seen only with an effort; and, when seen, is
also inferred to be the universal author of all things
beautiful and right, parent of light and of the lord of
light in this visible world, and the immediate source of
reason and truth in the intellectual; and that this is the
power upon which he who would act rationally, either
in public or private life must have his eye fixed.”
The Platonic Tradition
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Judgment of perception: ‘This is a triangle’
Mind is turned toward object perceived
But also to the form of a triangle
We perceive the thing as a triangle because we
apprehend the form
Plato’s Philosophy of Mind
This is a
triangle
Form
Object
Objects and Abstract Forms
• “You are aware that students of geometry, arithmetic,
and the kindred sciences assume the odd and the
even and the figures and three kinds of angles and
the like in their several branches of science; these
are their hypotheses, which they and everybody are
supposed to know, and therefore they do not deign to
give any account of them either to themselves or
others; but they begin with them, and go on until they
arrive at last, and in a consistent manner, at their
conclusion?”
Objects and Abstract Forms
• “And do you not know also that although they make
use of the visible forms and reason about them, they
are thinking not of these, but of the ideals which they
resemble; not of the figures which they draw, but of
the absolute square and the absolute diameter, and
so on -- the forms which they draw or make, and
which have shadows and reflections in water of their
own, are converted by them into images, but they are
really seeking to behold the things themselves, which
can only be seen with the eye of the mind?”
Plato’s Philosophy of Mind
Participation
This is a
triangle
Form
?
Perception
Object
Platonism’s problem
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We don’t perceive the forms
How do we know anything about them?
Aristotle’s answer: abstraction
Plato’s answers:
– Recollection
– The Form of the Good
Plato’s Philosophy of Mind
The Good
Participation
This is a
triangle
Form
Recollection
Perception
Object
Plato’s Beard
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How can we,
Limited to the realm of the senses,
Have access to a realm beyond the senses?
Dilemma:
– Reject possibility of knowing abstract truths, or
– Postulate some special faculty of knowledge
Plato’s Beard
• Our theory of meaning (semantics)
makes us postulate objects
(metaphysics) that we can’t know
anything about (epistemology).
• How do we bring these together?
Plato’s Beard
• ‘There are infinitely
many prime numbers’
Semantics
Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
Metaphysics
Shaving Plato’s Beard
• Semantics: The sentences don’t really
commit us to the troublesome objects
• Metaphysics: The objects are minddependent
• Epistemology: We have a faculty of knowing
the objects
The Semantic Strategy
• ‘There are infinitely
many prime numbers’
Semantics
Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
Metaphysics
‘||’, ‘|||’, ‘|||||’, ‘|||||||’, ‘|||||||||||’, . . . .
The Semantic Strategy
• Nominalism: There are no universals
• Abstract terms stand for nothing
– Socrates has courage —> Socrates is
courageous
– Courage is a virtue —> Courageous people
are virtuous (ceteris paribus)
– We have something in common —> ?
– Green is closer to blue than to red —> ?
• Fictionalism: abstract language is fictional
The Metaphysical Strategy
• ‘There are infinitely
many prime numbers’
Semantics
Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
Metaphysics
The Metaphysical Strategy
• Conceptualism: Universals are minddependent
• Plato’s Forms —> concepts in the mind
• There are universals, but we construct
them
The Epistemological Strategy
• ‘There are infinitely
many prime numbers’
Semantics
Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
Metaphysics
The Epistemological Strategy
• We have the ability to know universals
• Platonism (Plato, Philo, Augustine,
Aquinas, Descartes): We know certain
universals a priori
• Aristotle: We know universals by
abstracting them from particulars
Philo of Alexandria
• Realm of Forms: the
Intelligible World
• Forms are ideas in the
mind of God
• They are God’s blueprint
for creation
• God created Intelligible
World, then matter, then
world
The Intelligible World
• “For God, being God, assumed that a
beautiful copy would never be produced apart
from a beautiful pattern, and that no object of
perception would be faultless which was not
made in the likeness of an original discerned
only by the intellect.”
The Intelligible World
• “So when He willed to create this visible world
He first fully formed the intelligible world, in
order that He might have the use of a pattern
wholly God-like and incorporeal in producing
the material world, as a later creation, the
very image of an earlier, to embrace in itself
objects of perception of as many kinds as the
other contained objects of intelligence.”
The Word of God
• The Word of God contains the intelligible world
• Psalm 33: “By the Word of God were the heavens
made.”
• “. . . the world discerned only by the intellect is
nothing else than the Word of God when He was
already engaged in the act of creation.”
• The Word is the pattern of creation, the “idea of
ideas,” the “Man of God,” the “Second God”
How do We Know the Forms?
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Forms are ideas in the mind of God
We are created in God’s image (Gen 1:27)
Our minds are images of the mind of God
“Our great Moses likened the fashion of the reasonable
soul to no created thing, but averred it to be a genuine
coinage of that dread Spirit, the Divine and Invisible
One, signed and impressed by the seal of God, the
stamp of which is the Eternal Word. . . .”
Knowledge of the World
• Our minds and the world are both
stamped with the Word of God
Two Dilemmas
• Universals: we must either
– Reject the possibility of knowledge we
seem to have, or
– Postulate a faculty of knowledge to relate
us to universals
• Universality and Necessity: we must
– Reject our knowledge of universal and
necessary truths, or
– Postulate a priori knowledge
Origen (185-253)
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I John 1:5: “God is light.”
Forms as ideas in the mind of God (Philo)
Good —> God
God illumines the intelligible world for us
Augustine (354-430): God illumines our minds with
“inner light of truth”
God is light
• “. . . God is light; as John writes in his Epistle, ‘God is
light, and in Him there is no darkness at all.’ Truly He
is that light which illuminates the whole understanding
of those who are capable of receiving truth, as is said
in the Psalms 36, ‘In Thy light we shall see light.’ For
what other light of God can be named, ‘in which any
one sees light,’ save an influence of God, by which a
man, being enlightened, either thoroughly sees the
truth of all things, or comes to know God Himself, who
is called the truth?”
Origen’s and Augustine’s
Philosophy of Mind
Participation
God
Form
This is a
triangle
Illumination
Perception
Object
Aristotle
Aristotle’s Categories
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Substance man, the horse, Socrates
Quantity
6 ft tall, 235 square miles
Quality
white, tall, angry, wise
Relation
double, greater than
Place
at the mall, west of Austin
Time
today, at noon, for a week
Position
lying, sitting, standing
State
armed, puzzled, impressed
Action
hit, smile, do, walk, thank
Affection
to be hit, to be thanked
What are they categories of?
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Kinds of thing
Kinds of basic thing
Kinds of being
Correspond to grammatical functions
Substance
• All the other categories depend on
substance
• Qualities, quantities, relations, etc., are
always of substances
• There are many senses in which a thing
may be said to be
• But all depend on a focal meaning of
‘being’, substance
What is substance?
• A substance is a ‘this’
• It answers a question, ‘What is it?’
• A substance is always of a kind, having a
species (specific kind) and a genus (a
more general kind)
• Substance: a ‘this’ and a ‘such’
• Substance exists in a primary sense
• ‘What is there?’ ‘Substance.’
Primary/Secondary Substance
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A substance is a ‘this such’
A substance is a subject
We predicate other things of it
Primary substances: things; individual
objects
• Secondary substances: kinds
Criteria for Substance
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A substance is a ‘this such’
There are no degrees of substance
Substances admit contrary qualities
How is that possible?
Essential Properties
• Essential property: without it, the thing
wouldn’t be what it is
• Essential properties are necessary
• Thing has them by virtue of what it is
• Accidental property: without it, the thing
can remain the same
• Accidental properties are contingent
Essential Properties
• The essence of x =
–what it is to be x
–what x is by virtue of itself
–what x is by its very nature
–what is expressed by a definition
of x (a “formula for the nature of”
x)
What is a Substance?
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Matter
Form
Combination of matter and form
Essence
The river can remain the same even
though the water constantly flows
Four Causes
• Formal: relies on
essence or definition
• Material: matter
• Efficient: chain of
events, production
• Final: goal, purpose,
function
Essences and Causes
• St. Thomas Aquinas (12241274)
• Essences as causes
• Quiddity: “whatness”, “what it
is”— definition in re
• Nature of x: what makes x
what it is; that by virtue of
which x is what it is
Aquinas Identifies with Form:
• The essence of x = the properties
necessary to x, without which x would
not be what it is
• The quiddity of x = what corresponds
to x’s definition in the world
• The nature of x = what makes x what it
is
The Atomic Theory of Matter
• The atomic theory poses a
challenge to this conception
of substances
• Atomic theory: things are
composed of atoms;
properties of things depend
on nature and motion of
atoms
Dignaga (c. 450), Buddhist
• “Though atoms serve as causes of the
consciousness of the sense-organs, they are
not its actual objects like the sense organs;
because the consciousness does not represent
the image of the atoms. The consciousness
does not arise from what is represented in it.
Because they do not exist in substance just like
the double moon. Thus both the external things
are unfit to be the real objects of
consciousness.”
Nature and Quiddity
• We typically define a kind in terms of its
perceptual properties—the things
corresponding to its definition in the
world—its quiddity
• But what makes it what it is—its
nature—is its atomic structure
• Nature ≠ quiddity; nature => quiddity