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Anselm and Descartes Arguments

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Anselm Ontological Argument.
To learn about arguments, we might as well look at one. Here is a
famous argument from St. Anselm. It’s called The Ontological Argument.
(Note: There are many versions of this argument. I do not mean to
suggest this is the only or best way of rendering it. If you select a
different version for an assignment, your only obligation is to find
an argument at least as promising as this version.)
1.
1. God is that than which nothing greater can be thought.
2.
2. A God that exists is greater than one that doesn’t.
3.
3. If God does not exist, God is not that than which
nothing greater can be thought.
4.
4. From 3 and 1, we can use a rule called modus tollens
to infer that God does exist.
5.
5. Thus, God exists.
It is important to look at the nature of the claims in this argument.
The first premise is to be true by definition. A statement is one
whose truth value is settled by looking at the meanings of the words
within it. Such statements are called analytic statements. Suppose I
say "That Euclidean triangle has four sides." That sentence is false
just because of the meanings of the words in it; and no one who knows
what a Elucidean triangle is must investigate the world to determine
whether it is true. Anselm treated the proposition "God is that than
which nothing greater can be conceived" as an analytic proposition.
The definition of 'God' is just 'that than which nothing greater can
be conceived', at least as Anselm saw it.
(Side: Philosophers do not settle disputes with dictionaries.
Dictionaries give common usage. The purpose of a lexicographer people who write dictionaries - is to teach people how to use the
langauge well enough to communicate in daily life. In the highly
technical field of philosophy, common usage is insufficient. Common
uses are often loose and sloppy. Philosophers are trying to avoid that
sort of thing. If you think that is a problem for philosophy, take an
upper-level physics class on the nature of time, for example. You will
find exactly the same aversion to common usage. Besides, there are many dictionaries
and they do not all define words in the same way.)
Now, suppose you say that you think Anselm misuses the word ‘God’.
That would be fine by him. If he proves that that than which nothing
greater can be thought exists, you may call it whatever you like.
Premises 2 and 3 are not quite analytic. Instead, we’ll call them
conceptual claims. Conceptual claims deal with the meanings of words
and logical relations. Premise 2 is not to be true because of the
meaning of the word ‘God’, but because of all the meanings of the
words in the sentence. We do not need to do scientific investigation
to see if Premise 2 is true. The same is true of Premise 3.
Try to get this down: Arguments can be valid or invalid, sound or
unsound. Premises can be true or false, synthetic (which we’ll look at
next time) or analytic.
The PowerPoint on the next page might help to illuminate some of the key concepts
you will need to learn.
Descartes Cosmological Argument
Today we will continue to work on identifying parts of an argument.
We will use Rene' Descartes's argument for God's existence to set the
backdrop. Here is the relevant portion of Descartes's argument. This
comes from his third meditation.
"[t]hough the idea of substance be in my mind owing to this, that I
myself am a substance, I should not, however, have the idea of an
infinite substance, seeing I am a finite being, unless it were given
me by some substance in reality infinite
And it cannot be said that this idea of God is perhaps materially
false ,and consequently that it may have arisen from nothing [in other
words, that it may exist in me from my imperfections as I before said
of the ideas of heat and cold, and the like: for, on the contrary, as
this idea is very clear and distinct, and contains in itself more
objective reality than any other, there can be no one of itself more
true, or less open to the suspicion of falsity. The idea, I say, of a
being supremely perfect, and infinite, is in the highest degree true;
for although, perhaps, we may imagine that such a being does not
exist, we cannot, nevertheless, suppose that his idea represents
nothing real, as I have already said of the idea of cold. It is
likewise clear and distinct in the highest degree, since whatever the
mind clearly and distinctly conceives as real or true, and as implying
any perfection, is contained entire in this idea. And this is true,
nevertheless, although I do not comprehend the infinite, and although
there may be in God an infinity of things that I cannot comprehend,
nor perhaps even compass by thought in any way; for it is of the
nature of the infinite that it should not be comprehended by the
finite; and it is enough that I rightly understand this, and judge
that all which I clearly perceive, and in which I know there is some
perfection, and perhaps also an infinity of properties of which I am
ignorant, are formally or eminently in God, in order that the idea I
have of him may become the most true, clear, and distinct of all the
ideas in my mind. There only remains, therefore, the idea of God, in
which I must consider whether there is anything that cannot be
supposed to originate with myself. By the name God, I understand a
substance infinite, [eternal, immutable],independent, all-knowing,
all-powerful, and by which I myself, and every other thing that
exists, if any such there be, were created. But these properties are
so great and excellent, that the more attentively I consider them the
less I feel persuaded that the idea I have of them owes its origin to
myself alone And thus it is absolutely necessary to conclude, from all
that I have before said, that God exists."
My lecture on this: Descartes argues for God's existence as follows.
First, he finds within himself the idea of perfection. He wonders how
that idea could have gotten there. He makes the claim that effects are
never more real than their causes, so something just as real as
perfection must have caused the idea. But Descartes is not perfect.
Thus, he reasons that he could not have put the idea in himself.
Well, what could have put the idea there? Something perfect! So he
concludes that something perfect must exist. This perfect thing is
God.
Descartes uses a kind of proposition you should know. Some statements
are settled by observation. Any statement whose truth value is not
determined by the meaning of the words in it is called synthetic.
(That should be in bold. Notice that synthetic propositions are quite
different from analytic statements.) The statement "I find within
myself the idea of perfection" is synthetic. It is not part of the
definition of Descartes - or anyone else - that he or she has the idea
of perfection within himself or herself. Descartes was Descartes even
when he didn't have the idea of perfection. (If you think he was a
different person when he learned a new word, imagine this defense in
court. "I'm not the person who committed that crime. I have learned
some stuff since the time the crime occurred." Ba-boom-boom-crash!)
It is hard to figure out whether Descartes takes some of his other
claims to be analytic or synthetic. Is it a synthetic claim that
effects are never more real than their causes? Is it true just in
virtue of the concepts involved? He never tells us.
The following PowerPoint might help you understand Descartes. Have a look at it before
doing the Kant reading (Reading 4).
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