paai3 platonism
TRANSCRIPT
Philosophy as Adventures of Ideas
Week3
What We See Are Shadows of Ideas
Kazuyoshi KAMIYAMA
2017/4/04
CONTENTS
Thales
Pre-Socratic Philosophy
From what is everything created?
From where does everything come?
Permanence: Parmenides
Change: Heraclitus
Plato
The theory of Ideas 1
The theory of Ideas 2
Plato’s Realism (Platonism)
Rationalism
Plato’s Academy
References
ANCIENT GREEK ONTOLOGY: AN INTRODUCTION
MILETUSBEFORE THE 6TH CENTURY BC, MILETUS WAS CONSIDERED
THE GREATEST AND WEALTHIEST OF GREEK CITIES.
THALES(624-546BC)
from Miletus in Asia Minor
A pre-Socratic Greek philosopher and mathematician
“the first philosopher” in the Greek tradition
(Aristotle)
What is the Arche (the originating principle of nature
and the nature of matter)?
His answer: water
Aristotle “the riddle of existence”
Philosophy begins with a sense of wonder,
the wonder that there are things, rather than no
things.
"It was their wonder, astonishment, that first
led men to philosophise and still leads them.”
(Metaphysics (982b12) )
PRE-SOCRATIC PHILOSOPHY
The Pre-Socratic philosophers (or natural philosophers) asked
questions about "the essence of things“(Arche):
A. From where does everything come?
B. From what is everything created?
Ontology(Metaphysics): the discussions of these questions
B. FROM WHAT IS EVERYTHING CREATED?
Types of Answers
Monism(一元論): there is only one kind of ultimate
substance.
Pluralism(多元論): reality consists of two or more
independent elements.
Dualism(二元論): there are just two mutually
irreducible substances.
…
A. FROM WHERE DOES EVERYTHING COME?
(“THE ULTIMATE WHY QUESTION”)
Permanence vs. Change
PERMANENCE
Parmenides (of Elea): 514-460 BC
"Is" could not have "come into being" because
"nothing comes from nothing".
Existence is necessarily eternal.
Moreover, he argued that movement was impossible
because it requires moving into “the void”空虚, and
Parmenides identified "the void" with nothing, and
therefore (by definition) it does not exist.
That which does exist is The Parmenidean One, which
is timeless, uniform, and unchanging.
ZENO OF ELEA (490–430 BC)THE INVENTOR OF THE DIALECTIC(ARISTOTLE)
Zeno’s paradoxes
Achilles and the tortoise
Let us suppose that
movement is possible.
Achilles cannot catch up with
the tortoise (as shown in a right
picture), which contradicts
the facts. Therefore movement is
impossible.
NOTEDIALECTIC (ALSO DIALECTICS AND THEDIALECTICAL METHOD) 問答法(弁証法)
A method of argument for resolving disagreement that
has been central to European and Indian philosophy
since antiquity. The word dialectic originated
in ancient Greece, and was made popular by Plato in
the Socratic dialogues. The dialectical method
is discourse between two or more people holding
different points of view about a subject, who wish to
establish the truth of the matter guided by reasoned
arguments.
Zeno shows the Doors to Truth and Falsity (Veritas et
Falsitas)
CHANGE
Heraclitus (of Ephesus)(535–475 BC)
Panta rhei, “Everything flows“
"Everything changes and nothing remains still ...
and ... you cannot step twice into the same stream."
PLATO(428/427–348/347BC)
Dialogues対話篇: The Apology of Socrates, Meno,
Theaetetus, Republic
Theory of Ideas (Forms) イデア論
What is Circle?
Answer: Circle is …..
The Idea(or Form) of circle 円のイデア(形相) is the
description which applies to the blank ….. .
LOTS OF QUESTIONS
What is equilateral triangle?
What is natural number?
What is human being?
What is courage?
What is virtue?
What is justice?
・・・
LOTS OF IDEAS (FORMS)
the idea of equilateral triangle
the idea of natural number
the idea of human being
the idea of courage
the idea of virtue
the idea of justice
・・・
THE THEORY OD IDEAS 1
There is a correct answer in each question.
Various ideas exist objectively.
The ideas exist, and the activity that tries to
discover them by reasoned arguments
(philosophy) is possible and meaningful.
THE THEORY OD IDEAS 2
The changing material world as it seems to us (the
world of appearance) is not the real world, but only an
"image" or "copy" of the real never-changing world
(the world of existence, the world of Ideas).
The Allegory of the Cave
(洞窟の比喩)
What we see are shadows of real things
(https://www.youtube.com/watch?v=ivY8nmJ05ns)
PLATONIC REALISM(PLATONISM)
Ideas (Forms) exist independently of human beings
and are the only true objects of study that can provide
us with genuine knowledge.
Note: This has been the most fundamental philosophy
of many western mathematicians and physicists.
RATIONALISM
In epistemology, rationalism is the view that regards
"reason as the chief source and test of knowledge.“
(Wikipedia) Plato's ideas possess the highest and
most fundamental kind of reality and are accessible
only to reason and not to sense. Plato is a rationalist
philosopher. cf. empiricism
PLATO’S ACADEMY(387BC-529AD)
"Let no one ignorant of geometry enter here."
The Academy (Ancient Greek: Ἀκαδημία) was founded by Plato in ca.
387 BC in Athens. Aristotle studied there for twenty years (367 BC –
347 BC) before founding his own school, the Lyceum. The Academy
persisted throughout the Hellenistic period as a skeptical school,
until coming to an end after the death of Philo of Larissa in 83 BC.
Although philosophers continued to teach Plato's philosophy in
Athens during the Roman era, it was not until AD 410 that a revived
Academy was established as a center for Neoplatonism, persisting
until 529 AD when it was finally closed by Justinian I.
The Platonic Academy has been cited by historians as the first
higher learning institution in the Western world. (Wikipedia)
THE SCHOOL OF ATHENS BY RAPHAEL (1509–1510)
REFERENCES
広川洋一『プラトンの学園アカデメイア』講談社学術文庫、 1999年
Nothingness - Why is there something rather than nothing?
Plato (https://en.wikipedia.org/wiki/Plato)
Pre-Socratic philosophers
(https://en.wikipedia.org/wiki/Pre-Socratic_philosophy)
KEYWORDS
the riddle of existence
Thales
arche
ontology
monism
pluralism
Permanence vs. Change
Zeno’s paradoxes
dialectic
Ideas (Forms)
the allegory of the cave
realism(Plato’s realism, Platonism)
rationalism
Plato’s Academy