Transcript Aristotle - University of Arizona

Aristotle
• Aristotle: 384-322 BC
– born in Stagira in northern Greece
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maps:
http://www.plato-dialogues.org/tools/gk_wrld.htm
http://iam.classics.unc.edu/map/download/area_a7_outline.pdf
• Plato’s student in the Academy
– Leaves Athens after Plato’s death in
347 BC
– Teaches Alexander for 3 years
• Returns to Athens in 335BC &
establishes the Lyceum
• Alexander dies in 323 BC, when
Aristotle flees Athens
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• Range of Aristotle’s Work
– Virtually all areas of philosophy
• metaphysics (note the term)
• epistemology
• ethics & aesthetics
• logic
• protoscience: physics, biology,
astronomy
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Plato v Aristotle
• The General Structure of Universe
– Plato’s two realms
• the world of forms
• the world of sensible objects
– Aristotle’s unified universe
• forms exist only in individual
objects = substances
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Plato v Aristotle
• Knowledge
– Plato’s nativism
– Aristotle’s empiricism
• Self
– Plato: individual souls are immortal
– Aristotle: soul is immortal but not
individualized or personalized
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Matter, Form & Substance
• The Problem of Change
– Plato, Parmenides & Zeno deny
the reality of change
– They variously hold that the
sensible world is “illusory”
– Aristotle accepts the reality of
the changing, physical world &
needs a fundamental principle
to accommodate change
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Matter
• Matter = Pure Potentiality
– that which, in itself, is nothing
but which can become anything
• compare malleable clay
– that which permits persistence
through change
• compare the enduring clay
– that which is unintelligible but
fundamental???
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Form
• Form = Pure Actuality
– that which disciplines, directs,
constrains matter
• shape of the malleable clay
– that which makes matter become
what is real
– definable & intelligible
– exists in what is real
• even in sensible objects
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Substance
• Particular objects = what really
exists
– e.g. Socrates, tree, electron
• Substance = that which is the
subject of predication but not
itself predicated
– target of thought and language
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• Material v Immaterial Substance
– Some substances can change
while retaining their identity
• they contain matter + form
–I.e. all sensible substances
– Some substances cannot change
• they do not contain matter
–I.e. Celestial Objects, God
(the unmoved mover)
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Identity and Essence
• How change works in material
substance
– matter remains (compare Soc.
Security Number)
– form exchanged
• distinguish essential (substantial)
from accidental form
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• Essential Form
– determines genus/species
– makes a substance be the kind of
object it is
• e.g. the rationality of Socrates
• Accidental Form
– characterizes or qualifies a
substance without affecting its
identity
• e.g. the snubnosedness of
Socrates
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What’s Really Essential?
• Contrast generic and personal
essence
– Socrates, the rational animal
– Socrates, the inquisitive
philosopher
• Two types of essential forms?
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What’s Really Essential?
• All and only rational animals are
featherless bipeds
– which form is essential?
– How do we tell?
• Socrates is both a philosopher
and a convicted criminal
– which form is essential?
– How do we tell?
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Is Essence Subjective?
• The role of language
– Edward Sapir/Benjamin Whorf Hypothesis
• Edward Sapir (1884-1936): American linguist and
anthropologist
• Benjamin Lee Whorf (1897-1941): American linguist;
student of Sapir
• The language you speak determines or strongly
influences how you conceive of the world and may
even influence how you perceive the world
– compare
• “red,” “white,” and “blue”
• “red-or-white” and “blue”
• Is essence what we find or what we fabricate?
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Forms as Universals
• Form as that which is commonly
and simultaneously present in
different but similar individuals
as the basis of similarity
• How can one thing, i.e. a form,
simultaneously be in different
places?
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The Nature of Thought
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A person = (body + soul)
(body + soul) = (matter + form)
Hence, a person = (matter + form)
Soul = form
– soul is that which gives life in
virtue of giving rational
animality
– soul = essential form
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Universal Soul
• Soul = essential form
• Essential forms are Universals
– Plato’s essential form = Socrates’
essential form
– So, Plato’s soul = Socrates’ soul
• This generalizes for all people
• So, there is but one soul!
• Immortality is not personal!
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Thought and Form
• Soul is seat of cognition/thought
• Thought = recognition of form
• Recognition of form =
reproduction of form in the soul
• So, to think of a cat is to have
the form of the cat in the soul
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Objections
• Why doesn’t a thinker become what
he/she thinks?
– Matter is in the object
represented by thought but not in
the soul
• Is it possible to distinguish similar
things in thought since thought is the
reproduction of universal forms?
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The Four Causes
• Aristotle is convinced in the reality
of sensible objects & change
• Thus, he must offer a theory of how
it is possible to understand the
structure of sensible objects and
change
• Aristotle proposes four basic types
of causation or explanation aiming at
showing why, of necessity, things are
as they are by showing them to be
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instances of Universal Laws
Causation Fourfold Universality
• Material Causation
– based in the varieties of matter
• Efficient Causation
– based in the (infinite) sequence of
antecedent motion
• Formal Causation
– based in the varieties of form
• Final Causation
– based in intelligent or natural purpose
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The Unmoved Mover
• The universe must be temporally
eternal since the idea of the
(causal) beginning/end of the
universe is nonsense
• Still, why does the universe have
the structure that it does in fact
have? It could have been other
than it actually is.
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• There must exist something that
is not part of the changing,
structured universe whose
existence serves to explain the
universe’s structure
• This = the Unmoved Mover who
affects the world in the manner
of a beloved/desired object
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Unmoved Mover
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Immaterial
Unique
Pure Form
Unchanging
Eternal
Thinks, but only of itself
The Final Cause of the physical
universe
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Agental Causation
• Aristotle allows that agents
cause things to happen as a result
of their deliberation
• Perhaps this “agental” causation
is simply a type of final causation
or perhaps it is “sui generis”
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Questions
• Questions:
– is agental causation “free” or itself
the effect of other causes?
– does agental causation lead to
inexplicable or chance events
• the unintented result of intentional
action?
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• Jones decides to go to the
market to purchase food
• At the market he happens to
meet Smith & happily collects a
debt from Smith
• The debt collection was
– unplanned
– not universal = not what
normally happens
– is it a chance event?
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Chance
• The debt collection is a chance
event
• Chance events do have causes!
• Causes of chance events are
Accidental Causes
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Accidental Causation?
• A accidentally causes B iff
– A (normally) causes C
– C happens to be identical to B
• Eg: Planning to go to the market
(normally) causes one to visit the
store. Visiting the store happens to
be identical to collecting the debt
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Objection to Aristotle’s
Notion of Chance
• Contingent Identity
A happens to be identical to B
means that
A is contingently identical to B
• Chance presupposes contingent
identity
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• Contingent identity is introduced
into chance explanations as a
matter of happenstance or
coincidence
• This violates the condition that
causation is universal
• So causation by chance fails to
explain why things are as they
are!
• Aristotle errs, then, in saying
that chance is a kind of causation
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