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Kant’s Critique
Kevin Rogers
Kant for Dummies
• A simple explanation
Scope
• “If it is fools who say in their heart there is no God,
those who try to prove his existence seem to me to be
even more foolish.” (J.G. Hamann)
• Kant’s critique:
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What were his arguments?
Are they sound?
Are they relevant to contemporary arguments?
How do they affect the scope and usefulness of arguments
for the existence of God?
Immanuel Kant (1724 – 1804)
• Enlightenment Philosopher
• Unite empiricism (Locke) and
rationalism (Descartes)
• Theist (moral argument)
• Lutheran background
• Atheism dangerous to society
Critique of Pure Reason (1787)
• Critiqued:
– Ontological argument
– Cosmological argument
– Teleological (Design) argument
• Relevant sections:
– Transcendental Doctrine of Elements,
• Second Part,
– Second Division,
» Book 2,
• Chapter 3,
• sections 3 to 7
Definitions of Terms
• Impossible existence
– Square circles, married bachelors
• Contingent existence
– beginning
– Caused
– Do not have to exist
• Necessary existence
Necessary Existence (Necessary Being)
• Possibilities
– Uncaused
– No beginning
– Cause of all other things
• Stronger sense:
– Exists necessarily
– Impossible not to exist
– Must exist in all possible worlds
Traditional Arguments for Existence of God
• Types
– Teleological (Design)
– Cosmological (First Cause)
– Ontological
• More there are not, and more there cannot be
Overview of Arguments
• Cosmological and Teleological arguments:
– Been around since Plato and Aristotle
– Depend on observations about the actual world
– Some basis in Bible (Romans 1)
• Ontological Argument
– Invented in 11th century
– Nearly pure logical argument
– No reference to actual world
Kant’s Sequence
• Considers Ontological first
– Ontological fails
– Cosmological and Design depend on OA
– Hence fall with it
Ontological Argument
• Historical development prior to Kant
– Anselm
– Gaunilo
– Descartes
• Kant’s Objections
• Modern Arguments
• Assessment
St Anselm of Canterbury (1033 – 1109)
• Benedictine monk
• Archbishop of Canterbury (1093 –
1109)
• Proslogion (1078) = Discourse on
the Existence of God
Anselm’s Argument
• Hence, even the fool is convinced that something exists in the
understanding, at least, than which nothing greater can be conceived. For,
when he hears of this, he understands it. And whatever is understood,
exists in the understanding. And assuredly that, than which nothing
greater can be conceived, cannot exist in the understanding alone. For,
suppose it exists in the understanding alone: then it can be conceived to
exist in reality; which is greater. Therefore, if that, than which nothing
greater can be conceived, exists in the understanding alone, the very being,
than which nothing greater can be conceived, is one, than which a greater
can be conceived. But obviously this is impossible. Hence, there is no doubt
that there exists a being than which nothing greater can be conceived, and
it exists both in the understanding and in reality.
• (Proslogion chapter 2)
Simple Version
• If "that than which nothing greater can be
conceived" existed only in the intellect, it would
not be "that than which nothing greater can be
conceived", since it can be thought to exist in
reality, which is greater
• It follows that "that than which nothing greater
can be conceived" must exist in reality
Plantinga’s Summary of Anselm’s Argument
1. God is defined as the greatest conceivable being
2. To exist is greater than to not exist
3. If God does not exist then we can conceive of a greater
being that does exist
4. Thus if God does not exist then he is not the greatest
conceivable being
5. This leads to a contradiction
6. Therefore God must exist
Gaunilo of Marmoutiers
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11th-century Benedictine monk
In Behalf of the Fool
Refutes Anselm using a parody
1. The Lost Island is that than which no greater can
be conceived
2. It is greater to exist in reality than merely as an
idea
3. If the Lost Island does not exist, one can conceive
of an even greater island, i.e., one that does exist
4. Therefore, the Lost Island exists in reality
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No intrinsic maximum for the greatest
conceivable island
Is “a greatest conceivable island” a coherent
concept?
Rene Descartes (1596 – 1650)
• Father of Rationalism’
• Introduced the idea that existence is a
perfection
• Simplified argument:
– The very conception of God includes the
possession of all perfections.
– Existence is a perfection.
– Therefore, it is inconceivable that God does not
exist.
Kant’s OA Objections
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OA confuses existence and essence
Existence is not a predicate
Negation does not entail a contradiction
How can a conceptual conundrum in the mind
affect a being’s objective existence?
Confusing Existence and Essence
• Descartes’ simplified argument:
– The very conception of God includes the possession of
all perfections.
– Existence is a perfection.
– Therefore, it is inconceivable that God does not exist.
• Essence = properties (perfections)
• Existence is not a property
Existence is not a predicate
• Proposition = subject + predicate, eg
– A dog has 4 legs
– God exists
• Predicate contains properties of object
• Existence
– is an instantiation of an object
– is not a property
– is not a perfection
• Undermine Descartes’ version:
– Existence is a perfection:
– It would be more perfect to exist than not to exist.
Negation is not a Contradiction
• Some statements are necessarily true, eg:
– All bachelors are unmarried
– All squares have 4 sides
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Their negation entails a contradiction
“God does not exist” does not entail a contradiction
Thus “God exists” is not a necessary truth
Confuses “necessary truth” with “necessary being”
Conceptual Conundrum
• Anselm argues for concepts in our minds to the objective
existence of God
• How can a conceptual conundrum in the mind affect a
being’s objective existence?
Kant’s Conclusion
• [The Ontological Argument] “neither satisfies
the healthy common sense of humanity, nor
sustains the scientific examination of the
philosopher.“
• Is he right?
Response to Kant’s Objections
• Predicate Argument is Irrelevant
• Necessary Existence is a Property
Predicate Argument is Irrelevant
• Plantinga’s Comment on Predicate Argument
– Kant's point, then, is that one cannot define things into existence because
existence is not a real property or predicate in the explained sense. If this is what
he means, he's certainly right. But is it relevant to the ontological argument?
Couldn't Anselm thank Kant for this interesting point and proceed merrily on his
way? Where did he try to define God into being by adding existence to a list of
properties that defined some concept?
– If this were Anselm's procedure -- if he had simply added existence to a concept
that has application contingently if at all -- then indeed his argument would be
subject to the Kantian criticism. But he didn't, and it isn't. The usual criticisms of
Anselm's argument, then, leave much to be desired.
Necessary Existence is a Property
• Kant claims existence is not a property to
invalidate OA
• Applies this to necessary existence
• Necessary existence is a type of existence
• Hence necessary existence is a property
Does it Apply to Modern Arguments?
• Modal Ontological Argument
1. It is possible that an MGB exists
2. If it is possible that an MGB exists, then an MGB exists in
some possible world
3. If an MGB exists in some possible world, then an MGB
exists in every possible world
4. If an MGB exists in every possible world then an MGB
exists in the actual world
5. Therefore an MGB exists
Avoiding Kant’s Fire
• Now we no longer need the supposition that
necessary existence is a perfection; for obviously
a being can't be omnipotent (or for that matter
omniscient or morally perfect) in a given world
unless it exists in that world... It follows that
there actually exists a being that is omnipotent,
omniscient, and morally perfect; this being,
furthermore, exists and has these qualities in
every other world as well. (Plantinga)
MOA Limitations
• The MOA is not a proof
• But obviously this isn't a proof; no one who didn't already accept the
conclusion, would accept the first premise… Everyone who
understands and reflects on its central premise -- that the existence
of a maximally great being is possible -- will accept it. Still, it is
evident, I think, that there is nothing contrary to reason or irrational
in accepting this premise. What I claim for this argument, therefore,
is that it establishes, not the truth of theism, but its rational
acceptability. And hence it accomplishes at least one of the aims of
the tradition of natural theology. (Plantinga)
Essence of Argument
• If it is possible that a Necessary Being (NB)
exists then that NB must exist in all possible
worlds
• Outstanding Issues
– Is a NB possible
– Is the NB God?
Conclusion on OA
• Anselm
– It is impossible for God not to exist
• Plantinga
– If it is possible that God exists, then He must exist
– Rational to believe but not proof
Impact on Cosmological and Design Arguments
• CA and DA predated OA
• Kant believed CA and DA presuppose OA
– CA and DA may show a Necessary Being (NB) exists
– Rely on OA to show NB is God
Cosmological Argument
• Main attack is dependency on OA
– OA says God is NB
– CA
• argues for NB
• Identifies NB as God – relies on OA
• Kant accepts there must be NB
• Disputes we can show NB is God
Dependency Arguments
• CA Assumes NB is possible
• CA assumes NB is God
1. Necessary Existence is Possible
• The concept of a necessary being appears in both
arguments.
• The cosmological argument assumes that
necessary existence is at least possible since if it
is not possible it cannot be actual.
• This is a conclusion of the ontological argument.
• Thus the Cosmological Argument is dependent
on the Ontological Argument.
Necessary Existence is Actual
• Cosmological argument does not assume that
necessary existence is possible
• Necessary existence is actual and hence possible
• Approach currently used in science
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Dark Matter and Dark Energy explain galaxy motion
Cannot prove that they are possible
Don’t even know what they are
They are actual and must be possible
2. CA assumes NB is God
• The Cosmological Argument relies on the
Ontological Argument to associate the necessary
being with God.
– The Ontological Argument shows that God is a
necessary being and therefore exists
– The CA shows that a necessary being exists, but then
relies on the OA to infer that the NB is God
• Not necessarily so - discuss the KCA later
Additional Objections to Kant
• Space and time
– Kant argues space and time are eternal realities
independent of God
– Examples of necessarily existent that are not God
– Used this to argue for possibility of infinite past
– Augustine argued against this on theological grounds
– Confirmed by modern cosmology
• Pure Reason
– The CPR is a critique on the limits of Pure Reason
– The CPR is an example of Pure Reason
Kalam Cosmological Argument
• The argument
• Justifying the premises
• Argument Conclusions
The Argument
• KCA Syllogism
1. Everything that begins to exist has a cause
2. The universe began to exist
3. Therefore the universe has a cause
Justifying the Premises
• Premise 1 usually accepted as intuitively obvious
• Most effort justifying premise 2
• Philosophical arguments
– Impossibility of instantiating an actually infinite set
– Impossibility of traversing infinite sequence of causes
• Scientific discoveries
– Second law of thermodynamics
– The Big Bang
Argument Conclusions
• Big Bang marked beginning of matter, energy, space
and time
• Cause must be transcendent, timeless and powerful
• Attributes not derived from any a priori argument
• Doesn’t argue that cause is NB or God
• Limits to properties that are directly implied by the
empirical and logical evidence
Kant’s Critique of Design Argument
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Kant: design argument demonstrates a designer
Modifies the form of matter but not a creator
To demonstrate creator, we must rely on OA and CA
Only demonstrate the existence of an architect
Limited by the material with which he works
The design argument may still be valid, but it is just
limited in scope
Response to Kant
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Not a serious concern
Aim of arguments is to establish God’s existence
Not completely define God’s attributes
If the design argument is sound, then it is decisive
Main became Darwin’s theory of evolution
Provided naturalistic explanation of design for living
creatures
Fine Tuning Argument
• Craig’s formulation :
1. The fine tuning of the initial conditions of the
universe and of the constants in the laws of physics
are due to law, chance or design.
2. They are not due to law or chance.
3. Therefore they are due to design.
• Craig uses syllogism to argue for a designer
• Does not link back to OA
Craig’s Arguments
• Craig’s arguments are cumulative
– Cosmological: cause is transcendent, timeless, spaceless,
powerful, personal
– Fine Tuning: Designer
– MOA: Necessarily existent and maximally great
– Moral: Source of moral values and duties
– Resurrection: intervenes in history
– Personal: relates to us
• Arguments, not proofs
Kant’s Scepticism
• Man of his own time
• His views reflect influence of Enlightenment
• Claims cosmological argument based on the “spurious
transcendental law of causality”
• Reflects Hume’s scepticism of cause and effect
• Enlightenment aimed to achieve certainty but failed
• Cause and effect intuitively accepted to be true
• Kant’s desire for certainty is unrealistic
Why is Kant Considered Credible
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It is not to be denied that ever since Kant's time an impression has prevailed widely that the
old proofs are no longer defensible. Possibly the mere fact that an eminent thinker had
ventured to call in question such seemingly irrefutable arguments seemed by itself almost
equivalent to a disproof. But another reason also, extrinsic it is true to the merits of the
criticism, but none the less effective, operated in favour of this result. During the last century,
rationalism, in the form either of naturalism or of idealism, had become strongly entrenched in
the great centres of learning. It was only natural that thinkers who had discarded belief in a
personal God should applaud Kant's conclusion, even if they might hesitate to affirm that his
criticism of the proofs was in all respects sound. Thus it came about that those who admitted
the value of the traditional arguments were regarded as out of date. Often the validity of Kant's
objections is simply taken for granted, and the proofs of God's existence dismissed without
more ado. Even some of the apologists of revealed religion, eager not to be behind the fashion,
discard them as untenable. (Joyce)
Assessment
• Strong Points
– Existence is not a predicate
– The arguments are not proofs
• Weak Point
– Link between OA and CA/DA is dubious
Our Response
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Be aware
Don’t overstate
Craig is well aware of Kant
Craig’s argument are not subject to Kant’s critique
Craig’s opponents do not directly use Kant
Some of Kant’s arguments reappear
References
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Craig, W.L. Reasonable Faith: Christian Truth and Apologetics, 3rd edition, Crossway, Wheaton, Illinois,
2008.
Joyce, G.H., Principles of Natural Theology, Longmans, Green and Co., New York, Toronto, Bombay,
Calcutta, and Madras, 1922.
Kant, I. The Critique of Pure Reason, 2nd edition, 1787, translated by J.M.D. Meiklejohn, A Penn State
Electronic Classic Series Publication, Pennsylvania State University, 2010.
Koons, R.C. Western Theism, Lecture notes and bibliography from Dr. Koons' Western Theism course (Phl
356) at the University of Texas at Austin, Spring 1998, http://www.leaderu.com/offices/koons/, in particular
Lectures 5&9.
Plantinga, Alvin, God, Freedom and Evil, New York: Harper & Row Publishers, 1974. The pertinent section
on the ontological argument is quoted at http://mind.ucsd.edu/syllabi/02-03/01w/readings/plantinga.html.
Robson, Gregory, The Ontological Proof: Kant’s Objections, Plantinga’s Reply, KSO 2012: 122-171, posted
August 26, 2012 www.kantstudiesonline.net.
Worthing, M., Apologetics Intensive Lecture Notes, Section 05, Apologetics, proofs and science, 2012.
http://www.scandalon.co.uk/philosophy/philosophy.htm
http://plato.stanford.edu/entries/cosmological-argument/
http://www3.nd.edu/Departments/Maritain/etext/pnt.htm