17. Plato's Forms
(November 8, 2011)
0. Preliminary matters
a) The meaning of "metaphysics"
Aristotole called the subject “first questions” or “first
Study of most basic questions of reality
Overlaps with cosmology, logic, math, theology and
b) Our program for this unit
What is real?
Mind and bodies?
The question of free will
1. Introductory question: the nature of numbers
Where do elephants exist?
o Africa, zoo etc.
Where do numbers exist?
o Not physical objects
o Numbers are used to count physical objects, but they are not
themselves in physical objects
o Mental objects, like thoughts or dreams?
o Numbers must be public objects, non- physical objects
o Independent in our minds, but not located in physical space
o Not objects of perception but objects of thought
o Numbers are real things
Numbers appear to be real public objects, nonspatial, eternal, and not
perceptible but knowable
2. Plato's Forms
Another word, Plato’s word, for such public but non- physical,
nonspatial object is
Plato thought the forms were more real than ordinary physical
a) Properties of Forms