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Title: Introduction to Humanities Lecture 12 Anselm


1
Introduction to HumanitiesLecture 12Anselm
Aquinas
  • By David Kelsey

2
Saint Anselm
  • Saint Anselm of Canterbury lived from 1033-1109.
  • He was a monk and later Archbishop of Canterbury.
  • Wanted to see how far argument and reason could
    substantiate the central doctrines of
    Christianity.
  • He invented the ontological argument for the
    existence of God.

3
A priori vs.A posteriori arguments
  • A Posteriori Arguments
  • An a posteriori argument has at least one premise
    which is contingent. It has at least one premise
    that is a question of fact.
  • Examples the Cosmological and Teleological
    arguments for the existence of God
  • A priori arguments
  • Have absolutely no premises that are a question
    of fact.
  • Composed entirely of a priori claims.
  • An a priori claim true or false in virtue of the
    meaning of its words alone.
  • The ontological argument is an a priori argument

4
Defining GOD
  • According to the Judeao-Christian-Islamic
    tradition God is the greatest or most perfect
    possible being.
  • What can we infer about God from this?
  • If God is perfect, he has every perfection.
  • Thus, God is
  • Omnipotent maximally powerful
  • Omniscient maximally knowledgeable
  • Omnibenevolent is perfectly good
  • Omnipresent is everywhere
  • What other perfections might there be?

5
A Reductiofor Gods omnipotence
  • An argument that God must be omnipotent
  • Suppose God wasnt omnipotent.
  • Then there could be a being more powerful than
    God.
  • That would be greater than God.
  • But God is the greatest of all possible beings.
  • So God must be omnipotent.
  • This argument has the form of a reductio ad
    absurdum.
  • Reductios always assume the negation of the
    conclusion they are out to prove.
  • The argument then derives a contradiction
  • A contradiction
  • Asserts that something both is and isnt the case
  • cannot possibly be true
  • The contradiction above
  • The argument then concludes by asserting what it
    was to prove

6
The form of the Reductio
  • So here is the form of our reductio
  • 1. God isnt omnipotent.
  • 2. Thus, there could be someone more powerful
    than God.
  • 3. Thus, there could be someone greater than God.
  • 4. But, by definition, God is the greatest
    possible being there couldnt be someone greater
    than God.
  • 5. Thus, there both can and cant be someone
    greater than God.
  • 6. Thus, (1) is false God is omnipotent.

7
AnselmsOntological Argument
  • Anselms concept of God
  • Anselm uses the notion of God seen in the
    Judeao-Christian-Islamic tradition.
  • For Anselm God is something than which nothing
    greater can be conceived.
  • This is not the same concept as the greatest
    being we can conceive. Such a concept would be
    limited by the way us humans conceive of things.
  • Anselm is assuming the Great chain of being here.
  • If you run up and down the chain you find it easy
    to conceive of beings both lesser and greater.
  • Your mind is carried to greater and greater
    things

8
Anselms Reductio
  • Anselms argument is a Reductio Ad Absurdum. The
    basic form of the reductio
  • Assume God doesnt exist
  • But then God isnt the being than which nothing
    greater can be conceived.
  • But God is the being than which nothing greater
    can be conceived.
  • Thus, God exists.

9
The form of Anselms argument
  • Anselms argument
  • 1. God does not exist.
  • 2. By God is meant that than which nothing
    greater can be conceived, (or NGC).
  • 3. NGC does not exist (from 1 2)
  • 4. So NGC exists in the understanding but not in
    reality. (from 2 3)
  • 5. NGC can be conceived to exist in reality as
    well as the understanding.
  • 6. If NGC were to exist in reality as well as the
    understanding, it would be greater.
  • 7. NGC is not NGC (from 4 6)
  • 8. NGC cannot exist in the understanding alone.
    (from 7)
  • 9. NGC must also exist in reality (from 6 8)
  • 10. God exists (from 2 9)
  • 11. God does not exist and God exists (from 1
    10)
  • 12. Premise 1 is false (by 1-11 and reductio ad
    absurdum)
  • Thus, 13. God exists

10
Evaluating Anselms argument
  • Evaluating Anselms argument
  • Is Anselms argument valid?
  • Is Anselms argument sound?
  • Which premises might be false?
  • Premise 1
  • Premise 2
  • Premise 5
  • Premise 6

11
Denying premise 2
  • Denying premise 2
  • Some argue that premise 2 is false.
  • They say that such a definition of God is
    incorrect.
  • Thoughts

12
Denying premise 5
  • Challenging the fifth premise
  • Can you conceive of God as existing in reality?

13
Denying premise 6
  • Can we deny premise 6
  • We can do this by claiming that existence in
    reality is not a perfection.
  • Thus, a being that existed in both the
    understanding and in reality is not more prefect
    than a being that existed just in the
    understanding.
  • Anselms reply would probably go like this
    existence entails the ability to use all of ones
    perfections
  • Counter Is existence the kind of thing that can
    even be a perfection at all?

14
Defining God into existence
  • Defining God into existence
  • Note that this argument attempts to move from the
    essence of God to Gods existence.
  • It moves from our grasp of what God is, to the
    fact that God is.
  • Seems to be claiming that the existence of God is
    self evident
  • But can Anselm really define God into existence?

15
Refutation bylogical analogy
  • Refutation by Logical Analogy
  • Many people think that Anselms argument just has
    to be wrong for it just shows too much.
  • Cant we give an argument of the same form as
    Anselms, but for an obviously false conclusion.
  • Since the new argument isnt sound, neither is
    Anselms.
  • This move is called Refutation by logical analogy.

16
Gaunilos parody
  • Here is the argument
  • Assume 1. The island than which no greater can
    be conceived (GPI) does not exist.
  • 2. So GPI exists in the understanding but not in
    reality. (from 1)
  • 3. GPI can be conceived to exist in reality as
    well as the understanding.
  • 4. If GPI were to exist in reality as well as the
    understanding, it would be greater.
  • 5. GPI is not GPI (from 2 4)
  • 6. GPI cannot exist in the understanding alone.
    (from 5)
  • 7. GPI must also exist in reality (from 4 6)
  • 8. GPI exists (from 7)
  • 9. GPI does not exist and GPI exists (from 1 8)
  • 10. Premise 1 is false (by 1-9 and reductio ad
    absurdum)
  • Thus, 11. GPI exists

17
Anselms reply
  • Anselms possible replies to Gaunilo
  • He could give up or bite the bullet.
  • Gaunilos argument isnt valid
  • A premise from Gaunilos argument is false

18
Anselms best reply
  • Anselms reply
  • Can the greatest possible island even exist in
    reality?
  • Although the greatest possible being could have
    all the perfections to the greatest degree, could
    an island really have them?

19
Aquinas
  • Saint Thomas Aquinas
  • Lived from 1225-1274.
  • A monk whose writings have been deemed
    authoritative by the Catholic Church.
  • In 1244 became a friar. Later he became a priest
    and in 1323 was made a Saint.
  • Heavily influenced by the works of Aristotle.
  • In his work Summa Theologica he gave 5 different
    arguments for Gods existence.
  • He called these the 5 ways.

20
Aquinas on Aristotle
  • Aquinas on Aristotle
  • Aquinas was greatly influenced by the works of
    Aristotle.
  • But Aquinas thinks there is a fundamental mistake
    in Aristotles metaphysics.
  • Aquinas thinks Aristotle overlooks the notion of
    existence.
  • Aristotle on existence
  • Form is what actualizes a potentiality, matter,
    into an actually existing thing.
  • And efficient causes are what bring a particular
    substance into being.
  • But the world, existing eternally, has no
    efficient cause. Existence is just born in its
    form.

21
Aquinas on existence
  • So for Aristotle, Form brings existence along
    with it. But for Aquinas, a things existence
    differs from its essence.
  • The essence of any substance is both matter and
    form for such an object is different from
    something purely formal
  • For something imaginary like a phoenix, its
    essence being form and matter, it lacks
    existence.
  • So existence is something added to those
    substances that do in fact exist.
  • Likewise for spiritual substances, they are
    composed of pure form and existence.
  • It is this new understanding of existence which
    leads Aquinas to rethink Aristotles notion of
    efficient causation and subsequently Gods
    existence as unmoved mover.
  • We now turn to Aquinas famous 5 ways

22
Theism
  • There are 3 general argument patterns for Theism.
  • Theism, Atheism Agnosticism
  • We have so far seen one of these argument
    patterns the Ontological argument.
  • Ontological Arguments
  • Argue that by an analysis of the very concept of
    God he must exist.
  • Cosmological Arguments
  • The form of the argument is roughly this
  • There must be a first cause of all things and
    this first cause must be God.
  • Teleological Arguments
  • Argue for Gods existence via premises about the
    design or goals or purposes of things.

23
The 5 ways
  • The 5 ways
  • The first way about things causing change in
    other things.
  • The second way about efficient causation
  • The third way about things causing others to
    exist
  • The fourth way about things causing others to be
    good or noble.
  • The final way about purposes.

24
Aquinas 5 ways
  • The first 4 ways
  • Different versions of the Cosmological argument.
  • Each way uses a different sense of the word
    cause.
  • In each case Aquinas wants to show that there is
    an uncaused cause
  • All Cosmological arguments have a form like this
  • 1. There is something that causes everything
    else, I.e. a first cause.
  • 2. Only God could be a first cause.
  • 3. Thus, there is a God.
  • The final way a version of the teleological
    argument.

25
The first way
  • The form of the first way
  • 1) Things change.
  • 2) Change is an alteration in which something
    becomes actually what it was only potentially
    until then.
  • 3) Everything that changes must be made to change
    by another thing.
  • 4) But if one thing causes change in another,
    either the cause is a first cause of change or it
    is caused to change by another (from 3)
  • 5) There couldnt be an open causal chain of
    changing changers going back forever into the
    past.
  • 6) Thus, there is an unchanging changer, a first
    cause of change. (from 1 5)
  • 7) And this first cause is God.

26
Aquinas argument for the 3rd premise
  • The third premise 3) Everything that changes
    must be changed by another thing.
  • A change from potentiality to actuality can only
    be brought about by something that is already
    actual.
  • The ball and batter
  • Nothing can be both potential and actual in the
    same respect.
  • So nothing can change itself.
  • Thoughts on this argument? Can you think of
    anything that could change itself?

27
Aquinas argument for the 5th premise
  • The 5th premise There couldnt be an open causal
    chain of changing changers going back forever
    into the past.
  • In this case there is no first cause of change
  • Open causal chain an infinite number of things,
    one causing change in the other
  • Ball and Batter
  • But then there couldnt be any intermediate
    causes either
  • Such causes could only cause change if actualized
    themselves by some prior cause.
  • Ball and Batter again
  • But if there werent any intermediate changers
    there would be no change at all.
  • Thoughts on this argument?
  • Is it possible that we have intermediate causes
    of change without a first cause?
  • Maybe there is another possibility a closed loop
    of intermediate changers

28
Evaluating the first way
  • The first premise
  • says simply that things change.
  • Change Aquinas means the kind of change we see
    in the ball when it is hit by the bat.
  • The fourth premise
  • Assuming that everything that changes must be
    changed by another thing, if one thing causes
    change in another, either the cause is a first
    cause of change or it is caused to change by
    another.
  • The fifth premise
  • There is an unchanging changer, a first cause of
    change.
  • This thing isnt changed by anything else. It
    can cause change though.
  • Dominos
  • Question why suppose that there is just one
    unchanging changer?
  • The conclusion
  • This first cause is God
  • Question why suppose this first cause is God?

29
The Second Way
  • The Second way
  • 1) efficient causes come in series
  • Something cannot be the efficient cause of itself
    for to be so it would have to preexist itself,
    which is not possible.
  • And if you take away a cause you take away its
    effect
  • 2) Such series of efficient causes could not go
    on to infinity
  • If the series were infinite there would be no
    first cause.
  • If there were no first cause there would be no
    intermediate causes...
  • 3) So there must be a first efficient cause
  • 4) this everyone gives the name God

30
Evaluating the Second way
  • Challenging the Second way
  • Some things to notice
  • Notice the similarity between the first and
    second ways
  • The second way is focused on a specific kind of
    causation, efficient causation.
  • An efficient cause causes something to come to be
  • Example the hammer, the spark and the explosion
  • Evaluating the premises
  • Premise 1
  • Questions?
  • Premise 2
  • Questions?
  • Premise 3
  • Questions?
  • The conclusion
  • Questions?

31
The Third Way
  • Two ways in which a thing can exist
  • Necessary things cant fail to exist.
  • Contingent things come into and go out of
    existence.
  • The third way
  • 1. Some things must exist of necessity.
  • 2. There cant be an open causal chain of
    necessary things each causing the next to be
    necessary.
  • 3. Thus, something must be necessary per se.
  • 4, And this is God.

32
The first premise
  • The first premise
  • Says that something must be necessary.
  • So not everything can be contingent.
  • His argument
  • 1) consider if everything existed contingently.
  • 2) All contingent things must start to exist at
    some time.
  • 3) So all contingent things must fail to exist at
    some time. (from 2)
  • 4) But then there must have been a time at which
    nothing existed. (from 1 3)
  • 5) But if there had been such a time nothing
    would exist now.
  • From nothing you get nothing
  • 6) But things do exist now.
  • 7) Something must exist of necessity. This thing
    caused contingent things to come to be.

33
Finishing the 3rd way
  • The second premise
  • says that there cannot be an open causal chain of
    necessary things each causing the next to be
    necessary.
  • His argument
  • In this case there is no first cause of change.
  • But then there couldnt be any intermediate
    causes and so no change at all
  • Question?
  • The third premise
  • says that something must be necessary per se
  • Necessary Per Se
  • Something that owes its necessity to nothing
    else
  • it can cause the necessity of other things
    though.
  • Question?
  • The conclusion
  • Questions?

34
The Fourth Way
  • The fourth way
  • 1) Some things are good (noble and true).
  • 2) Some things are better (or more noble or
    truer) than other things.
  • 3) These better (more noble and truer) things
    have more good (are more noble and are truer) in
    accord with their distance from a maximum.
  • Comparative judgments
  • 4) if something that is maximally true, good and
    noble were not in existence then there would be
    no things possessing truth, goodness and nobility
    to a lesser degree.
  • So whatever is maximally good (noble and true) is
    the cause of whatever else that is good
  • 5) Thus, something is maximally good and causes
    everything else that is good (from 1 4)
  • 6) This maximally good thing we call GOD.

35
Finishing the argument
  • Something to notice
  • Notice the appeal that this argument makes to the
    great chain of being
  • The first 3 premises
  • The fourth premise
  • Question This seems to imply that the maximally
    good thing is the cause of whatever else is good.
  • Questions?
  • Premise 5
  • The conclusion

36
The fifth way
  • The fifth way
  • 1) Everything has a design, acts for a purpose.
  • 2) Something can only have a design or act for a
    purpose if it is directed to do so by a designer.
  • Ex arrows and archers
  • 3) Everything has a designer, which we call God.

37
The first premise of the Design Argument
  • The first premise
  • 1) Everything has a design, acts for a purpose.
  • Goal-directed behavior is observed in all natural
    substances
  • Their behavior hardly ever varies and is almost
    always turning out well
  • Just like we plant and harvest and store food for
    the winter, intention and design is pervasive
    throughout
  • Examples...

38
Understanding the fifth way
  • The fifth way
  • is a teleological argument for the existence of
    God.
  • Teleological Arguments
  • Most are arguments by analogy.
  • They usually rest on some analogy between things
    we know to be designed by humans and things we
    know not to be designed by humans, such as the
    universe as a whole.
  • The analogy is then made if the first has a
    designer so does the second, which is God.

39
Thoughts aboutthe fifth way
  • Thoughts about the fifth way?
  • Finding a relevant difference
  • Anyone see a relevant difference?
  • Things vs. universes?
  • Could something besides God be the designer of
    the universe?
  • Other possible designers
  • Gravity?
  • Evolution?
  • Aquinas reply
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