Substance

1
Substance

2
Particulars

• Particulars cant 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

3
Universals

• Universals can have multiple instances
• Properties red, triangular, large
• Relations between, on, love, friendship
• Kinds tiger, building, pencil, shortstop
• Books the Bible Worldly Wisdom
• Musical works Luckenbach, Texas Bachs Toccata
  and Fugue in D Minor

4
Are Universals Real?

• Realism yes, and mind-independent
• Conceptualism yes, but mind-dependent
• Nominalism no everything is particular
• Mind-dependent Mind-independent
• Real Conceptualism Realism
• Unreal Nominalism

5
Why think forms exist at all?

• Necessary for knowledge
• Without forms, we could
• Perceive
• Generalize
• But we couldnt
• 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

6
Platos 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
• Thats a contradiction
• So, nothing changes

7
Platos enemies Heraclitus

• That doesnt show that change is impossible
• It just shows that objects dont persist through
  change
• There are changes one object succeeds another
• You cant step into the same river twice.

8
Platos enemies Sophists

• The Sophists are relativists
• Man is the measure of all things
• Whats true for me might not be true for you
• Meaning might be relative too
• So, maybe you dont mean by your words what I
  mean
• Maybe my meaning changes over time

9
Platos enemies Skeptics

• The Skeptics deny the possibility of knowledge
• There is such a thing as truth
• We just cant get access to it
• How is it possible for us to communicate? I
  cant know what you mean (or even what I meant)

10
Forms explain how we can

• 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

11
Platos 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. . . .

12
Platos 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.

13
The Divided Line

• Visible World Intellectual
  World
• Shadows, Objects Mathematical Abstract
• reflections of perception forms forms
• Perceptions of Opinion Understanding Reason
• shadows, etc.
• Visible world is like a reflection of the
  intellectual world

14
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.

15
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.

16
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.

17
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

18
Meaning of the Allegory

• This entire allegory, I said, you may now
  append, dear Glaucon, to the previous argument
  the prison-house 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.

19
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.

20
The Platonic Tradition

• 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

21
Platos Philosophy of Mind

This is a triangle
Form
Object
22
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?

23
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?

24
Platos Philosophy of Mind

Participation
This is a triangle
Form
?
Perception
Object
25
Platonisms problem

• We dont perceive the forms
• How do we know anything about them?
• Aristotles answer abstraction
• Platos answers
• Recollection
• The Form of the Good

26
Platos Philosophy of Mind

The Good
Participation
This is a triangle
Form
Recollection
Perception
Object
27
Platos Beard

• 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

28
Platos Beard

• Our theory of meaning (semantics) makes us
  postulate objects (metaphysics) that we cant
  know anything about (epistemology).
• How do we bring these together?

29
Platos Beard

• There are infinitely
• many prime numbers
• Semantics
• Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
• Metaphysics

30
Shaving Platos Beard

• Semantics The sentences dont really commit us
  to the troublesome objects
• Metaphysics The objects are mind-dependent
• Epistemology We have a faculty of knowing the
  objects

31
The Semantic Strategy

• There are infinitely
• many prime numbers
• Semantics
• 
  Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
• Metaphysics
• , , , ,
  , . . . .

32
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

33
The Metaphysical Strategy

• There are infinitely
• many prime numbers
• Semantics
• 
  Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
• Metaphysics

34
The Metaphysical Strategy

• Conceptualism Universals are mind-dependent
• Platos Forms concepts in the mind
• There are universals, but we construct them

35
The Epistemological Strategy

• There are infinitely
• many prime numbers
• Semantics
• 
  Epistemology
• 2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31 . . . .
• Metaphysics

36
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

37
Philo of Alexandria

• Realm of Forms the Intelligible World
• Forms are ideas in the mind of God
• They are Gods blueprint for creation
• God created Intelligible World, then matter, then
  world

38
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.

39
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.

40
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

41
How do we know the Forms?

• Forms are ideas in the mind of God
• We are created in Gods image (Gen 127)
• 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. . . .

42
Knowledge of the World

• Our minds and the world are both stamped with the
  Word of God

Word
Word
43
God to Moses

• The powers which thou seekest to know . . . .
  present to your sight a sort of impress and copy
  of their active working. You men have for your
  use seals which when brought into contact with
  wax or similar material stamp on them any number
  of impressions while they themselves are not
  docked in any part thereby but remain as they
  were. Such you must conceive My powers to be,
  supplying quality and shape to things which lack
  either and yet changing or lessening nothing of
  their eternal nature.

44
God to Moses

• Some among you call them not inaptly 'forms' or
  'ideas', since they bring form into everything
  that is, giving order to the disordered, limit to
  the unlimited, bounds to the unbounded, shape to
  the shapeless, and in general changing the worse
  to something better. Do not, then, hope to be
  ever able to apprehend Me or any of My powers on
  Our essence.

45
God to Moses

• But I readily and with right goodwill will admit
  you to a share of what is attainable. That means
  that I bid you come and contemplate the universe
  and its contents, a spectacle apprehended not by
  the eye of the body but by the unsleeping eyes of
  the mind.

46
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

47
Origen (185-253)

• I John 15 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

48
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?

49
Jesus as the Word of God

• Such is the meaning of the expression, In Thy
  light we shall see light i.e., in Thy word and
  wisdom which is Thy Son, in Himself we shall see
  Thee the Father. Because He is called light,
  shall He be supposed to have any resemblance to
  the light of the sun? Or how should there be the
  slightest ground for imagining, that from that
  corporeal light any one could derive the cause of
  knowledge, and come to the understanding of the
  truth?

50
Origens and Augustines Philosophy of Mind

Participation
God
This is a triangle
Form
Illumination
Perception
Object