Great Philosophers of Ancient Greece: Plato and Aristotle
James A. Van Slyke, Ph.D.
Two Philosophers
Plato (428-348 B.C.)Born into wealth and political power
Rejected a political career after the death of Socrates
Socrates’ student
His school, The Academy, located next to his house
Taught both academics and political leaders
Died at the age of 81 at a wedding feast
Two Philosophers
Aristotle (384 -322 B.C.)Born in Macedonia 15 years after Socrates’ death
In 367 B.C Aristotle at the age of 17 moved to Athens and studied at The Academy for 20 years
Tutored Alexander the Great
Aristotle later set up his own school, The Lyceum, outside of Athens
Great library and students
Many free lectures
Theory or Common sense? Plato
Pointing towards the sky
Emphasized theoretical knowledge
Clothed in red the volatile element of fire
Aristotle Feet firmly
on the ground
Clothed in the colors of green (earth) and blue (water)
Emphasized the empirical, what can be demonstrated and observed
Plato’s Thought
The Republic (written 375 B.C.)Sought a definition of Justice
Explores several definitions
Statement of the aims of The Academy
CharactersSocrates – Narrator
Glaucon and AdeimantusPrimary respondents, elder brothers of Plato
ThrasymachusSophist
The Republic
Definitions of Justice
Objection of ThrasymachusJustice is not virtue, but foolishness
Used for the interest of the powerful
Self-interest is more important than morality
Objections of Glaucon and AdeimantusMeans to avoid punishment
Gain a good reputation; social approval
Plato tries to show that justice is a good to be sought for its own reward
The RepublicTo understand justice, the philosopher must understand “the form of the good”
Forms – Idea or Essence of something
That which unites things into a particular category
Theory of Ideas The allegory of the sun
The allegory of the cavePhilosopher is sent to rescue people from the cave
From the world of appearance to the reality of the good
The Republic
Plato’s society has three classes1. Ruling class – soldiers
Selected through competition
Philosopher Kings
2. Auxiliary soldiersCarried out necessary functions
3. Farmers and ArtisansGave consent to rulers
Virtuous city is based on a proper division of labor
The Republic
Inner soul is similar to the division of labor in the city
ReasonRules over the tempers and appetites
TempersFight and punish
Anger
AppetiteSexual desire
Hunger, thirst
The Republic
Justice is an individual in harmony with the three parts of the soul; discord leads to injustice
A proper balance of the soul is based on the exercise of reason
This leads to a just person and a just society
Thus, justice or goodness is its own reward
Better to fill the soul with understanding rather than simply fulfilling the appetites
Justice or goodness leads to a healthy soul and a healthy life
The RepublicEducation
ImaginationPoets and Drama, story
BeliefsEstablishing a contingent fact
MathematicsAbstract numbers
Geometrical proofs
Dialectic (philosophical) reasoningproposes a hypothesis and
tries to show that it leads to a contradiction or elenchus if successful the hypothesis is refuted
Tries to reach a premise that is unquestionable
Plato’s Cosmology
Form of the Good
Forms
stars/planets = divinities
humans
animals
plants
inorganic material more order, goodness, beauty, less corruptibility as we go up the hierarchy
Aristotle
More interested in the empiricalClassification of animal behavior
Theories of causationEfficient causation – sculptor
Material cause - stone
Formal cause – forms
Final cause – function something serves
Expanded and reformed Plato’s thoughtHylomorphic view of matter
Form and matter work together; interdependent
Aristotle
Understanding of the soulHierarchy of the soul
Different types of souls provide different functions
plants have vegetative/nutrition – about nutrient, reproductive, grow
animals have animal/sensitive – sensation, locomotion,
humans rational soul – intellect
