- Many topics which are today considered sciences started out as philosophies
- Philosophy emerged in Ancient Greece and India the same time as the
development of mathematics
Math text on geometry
5 axiom proofs of systems of geometry
What is justice?
Right and wrong?
Truth and falsity?
Student of Plato
Taught Alexander the Great
Wrote treatises on philosophy, physics, biology, rhetoric, etc
Work was lost, brought back to Europe by the Arabs in the
- Philosophies focus on “making a case”
o Arrive at a conclusion based on reasoning
- Making a case leads to arguments
o Has a premise and a conclusion
o Good argument
Conclusion supported by premise
Begging the question
Assuming the conclusion as the premise
o Evaluating Arguments
Identify premise and conclusions
Evaluate the premises
Do you think they are true? Why?
Can you give reasons to reject them?
Do you have reasons to accept them?
Evaluate the link
Does the conclusion follow the premises?
Does the reason for accepting the premise depend on an
Arguments in support of premises but there has to be an end
o Observation/personal experience
o Pure reason (math)
- Evaluating Authorities
o When can we rely on a source of information
o Trusting yourself
When should I trust myself to “get it right”?
Do I have the training/background needed to answer questions
Am I motivated to arrive at a particular answer regardless of
what the evidence shows?
The Existence of God
- Unlike Greek, Scandinavian or other gods that have supernatural powers but
still have weakness and limits
- The monotheistic God is
o Perfectly benevolent
o The ontological argument (Anselm, Descartes…)
o Cosmological (Aquinas)
o Teleological/Design (Aquinas, Paley…)
o The argument of evil (Hume, Mackie…)
o Does the definition of God require/imply God’s existence?
o Anselm claims that it does, in an argument that goes:
God is perfect, by definition
But existence is a perfection
So, by definition, God exists
“Something than which nothing greater can be thought”
o Invites us to imagine such a thing as non-existent
o Some greater than non-existence would be existent
o Therefore, it is greater to be such that you cannot be thought to not
exist than to be such that you can thought to not exist, God cannot be
thought to not exist
o It’s greater to be the creator who made all from nothing than to not be
the creator, God must be such a creator
o Not an atheist, but not convinced by Anselm’s argument
o Worries that if understanding the idea of God and believing God exists
are so closely liked, then it’s odd that the argument exists at all
o The distinction between what is understood and existence remains
The thought is distinct from the thing thought of
o How do you understand the word “God”, when we have no clear grasp
of what he is (by ‘species and genius’)? All we have is Anselm’s verbal
formula, not an understanding of God’s nature.
o This keeps the argument from convincing me, since the verbal
formula “that which is” doesn’t have the power to persuade me that
there is such a thing.
o I imagine it, but I don’t assume that it exists as I imagine it, only if I
really take it to be as I imagine it do I wind up concluding that it must
exist, but that’s exactly what’s to be proven.
o The Island
A classic example of one important way to criticize arguments:
present another argument with the same structure that is
Consider the most perfect island (an island which none greater
can be thought)
Surely, if Anselm’s argument works, this island exists
But that’s crazy
o Guanilo emphasizes the gap between two thoughts
If there is a God, he is greater than anything else we can
Because God is greater than any other thing we can conceive,
he must exists
o The difference between thinking and understanding is important
The idea of a nature, we can understand
Words, we can think without full understanding
o Guanilo may be dubious about our ability to understand what God is,
or he may be saying that it’s only by understanding God, not by verbal
arguments, that we can see that God exists.
- Three types of arguments for God’s existence
Some feature of the universe that demonstrates God’s
Something about the definition or nature of God is taken to
demonstrate God’s existence
Some aspect(s) of the apparent goal-directedness of things in
the world are claimed to be best explained by the intervention
of a supernatural creator/designer
Many topics which are today considered sciences started out as philosophies. Philosophy emerged in ancient greece and india the same time as the development of mathematics: euclid. 5 axiom proofs of systems of geometry. Wrote treatises on philosophy, physics, biology, rhetoric, etc. Work was lost, brought back to europe by the arabs in the. Philosophies focus on making a case : arrive at a conclusion based on reasoning. Making a case leads to arguments: has a premise and a conclusion, good argument. Assuming the conclusion as the premise: evaluating arguments. Arguments in support of premises but there has to be an end: authority, observation/personal experience, pure reason (math) Evaluating authorities: when can we rely on a source of information. Unlike greek, scandinavian or other gods that have supernatural powers but still have weakness and limits. The monotheistic god is: omnipotent, omniscient, perfectly benevolent. Pro: the ontological argument (anselm, descartes , cosmological (aquinas, teleological/design (aquinas, paley )