• Philosophy:

The study of questions that cannot be answered solely by appealing to sense experience.

• Philosophical Questions

• Examples:

– What are numbers?

• Do they exist only in our minds?

• Do we create them or discover them?

– What can we really know on the basis of sense experience?

– Do human beings really have a free will?

– So, to “philosophize about x” involves not just thinking about x, but thinking about (how one goes about) thinking about x.

– This is what it means to “think reflexively.”

• Main divisions within Philosophy:

• Metaphysics and Ontology (the study of what is real or what exists)

• Epistemology (the study of knowledge)

• Value Theory (the study of values)

• Logic (the study of reasoning)

• Metaphysics and Ontology:

• The study of what is ultimately real, of what really exists.

– What are numbers?

– Is there really a ? – Do minds exist independently of bodies?

– Is there such a thing as free will?

• Epistemology:

• The study of knowledge.

– What is knowledge?

– What is the difference between knowledge and (mere) true ?

– What sorts of things can we have knowledge of?

– Can we trust the veracity of sense experience?

• Value Theory:

1) Ethics

– The study of moral values.

• What makes things morally right or morally wrong?

2) Aesthetics

– The study of artistic values.

• What is beauty?

• Logic

The study of the proper forms of reasoning.

Helps us evaluate the quality of an argument.

An Argument:

A group of statements where one or more statements (the premises) purport to offer evidence for one other statement (the conclusion).

• Kinds of Arguments • Inductive:

• Inductive arguments are probabilistic. They attempt to show that if the premises are true, then the conclusion is probably true.

• Example:

Most TAs are poor.

We are TAs.

So, we are probably poor.

• Deductive:

• Deductive arguments are not probabilistic. They attempt to show that if the premises are true, then the conclusion must be true.

• Example:

Mo’ money, mo’ problems.

Miley Cyrus has mo’ money.

Therefore, Miley Cyrus has mo’ problems.

• Validity

• In a valid argument, the truth of the premises guarantees the truth of the conclusion.

– I.e., if the premises are all true, then the conclusion must be true.

• So, an argument can be valid even with false premises and a false conclusion. What it cannot have is all true premises and a false conclusion.

• Validity is a formal property of arguments.

• All humans are mortal.

• Jones is human. • Jones is mortal.

– All A’s are B’s.

– x is an A.

– x is a B.

• All test reviews are wicked fun.

• This is a test review.

• This is wicked fun.

• In a reductio ad absurdum argument we begin by assuming the opposite of what we are trying to prove.

• We then derive a contradiction (an “absurdity”) from this assumption to show that it cannot be true

• (and so that what we are trying to prove must be true).

• Reductio Ad Absurdum Example

• Suppose philosophy is not your favorite subject.

• Your favorite subject is the area of study that is the most awesome and fascinating.

• Philosophy is the area of study that is the most awesome and fascinating.

• So philosophy is not your favorite subject, and philosophy is your favorite subject. (an absurdity)

• Therefore it is false that philosophy is not your favorite subject.

• A priori vs. A posteriori Knowledge

• If we can establish truth without sense experience, this is a priori knowledge.

– Example: All wizards know magic.

• If we must appeal to sense experience (perception, observation, etc.) to establish truth, this is a posteriori knowledge.

– Example: Someone in this room is a wizard. • A priori vs. A posteriori Arguments

• An argument is a priori if all of its premises are a priori, i.e., if their truth can be established without appeal to sense experience.

– Example:

• An argument is a posteriori if at least one of its premises is a posteriori, i.e., if the truth of at least one premise can be established only by appeal to sense experience.

– Example:

• The Ontological Argument

• From the Proslogion, by

• Anselm, Bishop of Canterbury,

• c. 1077

• An A Priori Argument

• Anselm’s “Ontological Argument” is the only a priori argument for the .

• Anselm’s argument does not rely upon any knowledge we might have gained through sense experience.

• His argument is entirely “conceptual.”

– In effect, he thinks the existence of God follows from the very concept or definition of what “God” means.

• Anselm’s conception of God:

• God = A being than which none greater can be conceived …

– that is, a being such that one cannot conceive (or think) of anything greater.

– Types of Existence

• Existence in the Understanding

• Existence in Reality • God exists in anyone’s understanding once they are told about a being-than-which-none- greater-is-possible

– Anyone can understand this concept

• So God exists in the understanding (at the very least)

– Even for “The Fool”

• Anselm: Existence (“in reality”) is a greatness-making property.

• This mean that, for any given thing, that thing has more “greatness” if it exists (i.e., if it “exists in reality”) than if it doesn’t (i.e., if it exists only “in the understanding”).

– $20 in your pocket beats $20 in your imagination!

• Anselm’s Argument:

• 1. A being than which a greater is not possible exists in the understanding.

• 2. If something exists only in the understanding, then it might have been greater than it is.

• 3. Suppose (for reductio) that a being than which a greater is not possible exists only in the understanding (i.e. not in reality)

• 4. Then a being than which a greater is not possible might have been greater than it is.

• 5. So a being than which a greater is not possible is a being than which a greater is possible.

• 6. So premise 3 is false.

• 7. So a being than which a greater is not possible exists in reality in addition to the understanding.

• 8. God=def. a being than which a greater is not possible.

• 9. So God must exist in reality as well as in the understanding—it is impossible that God not exist.

• Gaunilo’s Strategy:

• Gaunilo can’t say exactly where Anselm’s argument goes wrong. • He thinks it “proves too much,”

– i.e., that if it works regarding “God,” then it must also work for any concept whatsoever.

– But, since it obviously doesn’t work for any concept whatsoever, it must not work in the case of God either.

• Gaunilo’s Argument:

• 1. An island than which a greater is not possible exists in the understanding.

• 2. If something exists only in the understanding, then it might have been greater than it is.

• 3. Suppose (for reductio) that an island than which a greater is not possible exists only in the understanding (i.e. not in reality)

• 4. Then an island than which a greater is not possible might have been greater than it is.

• 5. So an island than which a greater is not possible is an island than which a greater is possible.

• 6. So premise 3 is false.

• 7. So an island than which a greater is not possible exists in reality in addition to the understanding.

• 8. Consequently, that island than which a greater is not possible cannot not exist in reality .

• 9. That is, that island than which none greater is possible must actually exist.

• Oh really?!

• Cosmological Argument

• The Cosmological Argument:

• An a posteriori argument because it begins with a premise based on observation: that the universe exists and is subject to change.

• It tries to show that for this to be so there must exist something outside the universe which can cause or explain its existence.

• Aquinas’ Second Way: Summa Theologica: c. 1270

• 1. Some things are caused to exist by things that already exist.

• 2. Nothing can cause itself to exist.

• 3. This series of prior causes cannot go on to infinity.

• 4. Therefore there must be a first cause—an uncaused causer.

• 3. This cannot go on to infinity.

– i.e., without a first cause, nothing else would have happened, and so nothing would be happening now.

– But things are happening now.

– So, the series cannot go on to infinity.

– “Circular” Reasoning

• Aquinas argues that there must be a “first cause” to the universe, because, if there isn’t, then the series of prior causes would have no beginning.

• Aquinas argues that the series of prior causes must have a beginning, because, if it didn’t, then there would be no first cause.

• So, Aquinas reasons that there must be a first cause, because, if there wasn’t, then there wouldn’t be a first cause!

• “Begging the Question”

• An argument “begs the question” when it simply assumes the very point it is trying to prove.

– Such arguments don’t prove anything new: they only “prove” what has simply been assumed without argument.

– But they can sound “convincing” if they aren’t clearly stated.

• Arguments that God exists: Review

• Ontological: the existence of God follows from the very concept of God.

– Example: Anselm’s Ontological Argument

• This is the only a priori argument for the existence of God.

• Cosmological: The existence of God is posited to explain the existence of (change in) the world.

– Example: Aquinas and Clarke

– This is an a posteriori argument, in that it relies on something we know only from sense experience—namely, that there is change in the world.

• The Problem of

• Why would a good God create a world where bad things happen?

• “The ”

1. An all knowing being would know about any and all evil in the world.

2. An all powerful being would be able to prevent evil from happening in the world.

3. An all good being would want to prevent evil from happening in the world.

4. But, evil exists in the world.

5. So, it must be false that there is any being that is all knowing, all powerful, and all good.

i.e., there is no God.

• :

• An explanation for why God, a being who is all-knowing, all-powerful, and all-good nevertheless allows evil to exist in the world.

• Swinburne’s Theodicy

• “The problem is that God cannot give us these goods… without allowing much evil on the way.”

• The maximum amount of good that God can give us requires the existence of some evil.

• “Absence of Good” vs. “Positive Evil”

The presence of “positive bad states” vs. the lack of perfect goodness in the world

• The Problem of Evil concerns only the presence of “positive bad states”

– The lack of perfect goodness is not evidence against the existence of God

• Positive Badness (Real Evil)

• It is only the existence in the world of “positive evil” that the theist must explain.

– These explanations, recall, are called “.”

• Swinburne divides “positive badness” into two categories (and offers a different theodicy or explanation for each). They are:

– Natural Evil, and

– Moral Evil.

• Moral Evil vs. Natural Evil

• Natural Evil

– All evil not deliberately caused by human beings (directly, or through negligence).

• e.g., natural disasters; any suffering not caused by human choices.

• Moral Evil

– All evil caused by human beings doing what is morally wrong.

• e.g., homicide; i.e., suffering caused by humans freely doing bad things:

– i.e., by “sin.”

• Moral Evil and Free Will

• He argues that “moral evil” is the result of human beings having a free will. • Moral evil is the result of our “misusing” our free will (i.e., is the result of human “sin.”)

• “It is not logically possible…that God could give us such free will and yet ensure that we always use it in the right way.”

• Benefits of Natural Evil

– Natural evil makes “… it possible for humans to have the kind of choice the free-will defense extols”

• It motivates us to understand the natural world (in order to prevent natural ).

• And it provides opportunities for us to learn things like courage and compassion—it promotes human “growth.”

• Swinburne’s Theodicy

• “Moral Evil” is caused by human free will, not by God.

– But the “badness” humans cause is “outweighed” by the goodness of our having free will.

• “Natural Evil” is created by God because it is needed in order for us to achieve a greater amount of goodness.

– So, again, its “badness” is outweighed by a greater goodness.

• What About Animal Suffering?

• “For animals too … there are more worthwhile things” than pleasure, and these greater goods are possible only if natural evil is possible.

– i.e., like humans, they benefit from the opportunity to suffer!

• So, in the end, both human and animal suffering (when not caused by human free will) makes us all better. And that means it’s not “really evil.”

– apparently according to Swinburne!