Plato

1
Platos Metaphysics
Doctrine of Separationism (or Two Realms)

• Changing world of particular things
  characterized by identity and difference
• World of unchanging, immaterial, and eternal
  Forms.

2
Realm of the Forms - Intelligibles
WHITENESS/BROWNNESS
TALLNESS
NYLONNESS
FRUITNESS
Realm of the Physical World - Sensibles
Different Substances
Same Attributes
Identity in Difference
How do we explain real identity in real
difference?
NYLON
TALL
TALL
NYLON
WHITE BROWN
WHITE BROWN
FRUIT
FRUIT
Apple
Banana
Linda
Rover
Dax
Bill
3
Realm of the Forms
BEAUTY
Realm of the Physical World
Same Attribute
Beautiful
Beautiful
Identity in Difference
Different Persons
Angelina Jolie
Helen of Troy
4
The Forms
Hypothetical entities designed to explain how
numerically or quantitatively distinct things can
be qualitatively identical.
The Basic Argument
1. If identity in difference exists, then the
Forms exist.
2. Identity in difference exists.
So, 3. the Forms exist.
5
Beauty (f1) in Angelina and beauty (f2) in
Helen are the same, but Angelina (A) and Helen
(H) are not the same.
F
A is f1
H is f2
Two numerically distinct things can only have
identical properties if there are higher entities
that make this possible.

• F must be distinct from f1 and f2, otherwise F
  could not be the same thing in f1 and f2.

• F must be identical with f1 and f2, otherwise
  there is no basis for saying that A and H have
  the same attribute.

6
The Forms are universal entities so other things
can participate in their existence.
The Forms are also concrete, for they are
substances or things, though distinct from
physical things.
Individual physical things participate in the
forms by having the natures of the forms.