Title: Introduction to Humanities Lecture 12 Anselm
1Introduction to HumanitiesLecture 12Anselm
Aquinas
2Saint 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.
3A 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
4Defining 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?
5A 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
6The 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.
7AnselmsOntological 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
8Anselms 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.
9The 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
10Evaluating 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
11Denying premise 2
- Denying premise 2
- Some argue that premise 2 is false.
- They say that such a definition of God is
incorrect. - Thoughts
12Denying premise 5
- Challenging the fifth premise
- Can you conceive of God as existing in reality?
13Denying 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?
14Defining 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?
15Refutation 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.
16Gaunilos 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
17Anselms 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
18Anselms 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?
19Aquinas
- 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.
20Aquinas 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.
21Aquinas 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
22Theism
- 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.
23The 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.
24Aquinas 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.
25The 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.
26Aquinas 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?
27Aquinas 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
28Evaluating 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?
29The 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
30Evaluating 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?
31The 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.
32The 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.
33Finishing 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?
34The 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.
35Finishing 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
36The 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.
37The 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...
38Understanding 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.
39Thoughts 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