1. (a) Who is St. Thomas Aquinas? About when and where did he live?

Saint Thomas Aquinas was a 13th century Italian philosopher and theologian.

(b) Present Aquinas' "Second Way" to prove that God exists.

(1) The natural world includes events that occur.
(2) In the natural world, every event has a cause, and no event causes itself.
(3) In the natural world, causes must precede their effects.
(4) In the natural world, there are no infinite cause/effect chains.
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(5) Therefore, there is an entity outside of nature (a supernatural being), which causes the first event that occurs in the natural world.
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(6) Therefore, God exists.

(c) Give the rationale for each premise of the argument (lines (1)-(4)).

P1: This is undeniable. Here we are. There are these events happening, such as the giving of this lecture, the walking by me across this room, the rain storm yesterday. This is obvious.

P2: Let's take these in turn. If you think about, the claim that every event has a cause seems very plausible. We assume this all the time. If you hear a noise in the hallway, you assume it has a cause-maybe a person, or an animal, or even just something falling over. And that falling over also has a cause-the wind, the loss of adhesive, ... . This is not to say we always know the cause of any event. Very often it is difficult or impossible to know what caused something. But I take it we all agree that every natural event has a cause. Nothing just happens uncaused.

I'd say it is just part of the concept of causation that nothing causes itself. That doesn't make any sense. All events that occur were caused to occur by other events, events that came before.

P3: This, too, just seems part of the concept of causation. In fact, I would say that (2) and (3) are analytic, or relations of ideas. Just as it follows from the concept of a triangle, that all triangles have three sides, it follows from the concept of causation, that nothing causes itself, and causes always precede their effects.

P4: Aquinas gives a sub-argument for (4):

(4.1) Any infinite cause/effect chain would have no first member (no "first cause").
[by definition]
(4.2) If a causal chain has no first member, then it will have no later members.
[since to take away the cause is to take away the effect]
(4.3) But there exists a causal chain with later members.
[these are the events we witness; see P1]
(4) Therefore, there are no infinite cause/effect chains.
[follows from (4.1)-(4.3)]

This argument seems pretty good. I mean, if there is no first member of the chain, then how could the chain get started. Any existing cause/effect chains certainly had to start somewhere, right?


(d) Explain the inference from lines (1)-(4) to line (5).

From (1) - (3) we get that there is this chain of causes extending back into the past. From (4) we get that the chain is not infinite -- it has a first member. But in order for this first event to obey the principle contained in (2), it must have a cause. But in order for it to be the first event in nature, it can't have a cause in nature. The only option left seems to be that it has a cause, but this cause is "supernatural." It is caused by an entity that exists somehow not in nature.

(e) Explain the inference from line (5) to line (6).

In (5), we established the existence of this entity. It seems to have some of the attributes of God -- for instance, it is the creator of the universe (it got the whole thing started); and it's got to be very powerful, since, again, it caused the whole universe to exist. And it's "supernatural," and people often say that about God.  Since God has other attributes, (5) certainly doesn't deductive entail (6), but it does make (6) more likely.

(f) Present and evaluate the main objection to Aquinas' argument that we discussed in class.

The most interesting objection to Aquinas' argument is to premise (4), the claim that there are no infinite cause/effect chains -- that claim that the chain of events extending into the past couldn't go back forever -- that is had to start somewhere.

Well, Aquinas gave a little subargument for this premise (see above). So if we don't accept the premise, we need to find something wrong with that subargument. I think (4.2) is the questionable premise. Aquinas gives it in his slogan that if you remove the cause you remove the effect. But if you "take away" the first member by making the chain infinite, you're not really removing anything. Rather, you're just adding causes before it. Every event would still have a cause. There would just be infinitely many of them.

Moreover, we have independent reasons to think it is possible for the chain to go back forever.  It is certainly perfectly coherent to imagine that the universe lasts forever in the future. And it just seems just as perfectly coherent to imagine that the world goes infinitely far back into the past. Why not? We can imagine it. It is not a contradiction to suppose it. Therefore, it is possible. But Aquinas' argument relies on the claim that it is impossible. So the argument is unsound because premise (4) (of the main argument) is not true.

2. (a) Who is G.W. Leibniz? About when and where did he live? Tell me a fun fact about him.

G.W. Leibniz was a 17th century German philosopher, mathematician, statesman, physicist, geologist, linguist, historian, and more.  He invented calculus, independently of Newton.

(b) What is the Principle of Sufficient Reason (PSR)?

PSR: For anything that exists, there is a reason why it exists and why it is as it is rather than some other way.

(c) Present Leibniz's Argument from Sufficient Reason.

(1). The world exists.
(2). If the world exists, then there is a reason why the world exists.
(3). If there is a reason why the world exists, then there is something outside the world that the world depends upon for its existence.
(4). If there is something outside the world that the world depends upon for its existence, then there is a necessarily existing creator of the universe.
(5). Therefore, there is a necessarily existing creator of the universe.
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(6). Therefore, God exists.

(d) Give the rationale for each premise of the argument (lines (1)-(4)). Define any technical terms.

P1: We can know this is true, just from the fact that we know that we exist. If you exist, then there is at least one contingent thing. Even if there is just one contingent thing, then the world exists. Of course, we all know that there is more than that.  Whatever it is -- however many contingent things there are -- the world is the aggregate of all of the contingent things.

the world - the aggregate consisting of every contingent thing that ever did exist, does now exist, or ever will exist.

contingent - a contingent thing is a thing that exists but that might not have existed.

P2: PSR entails this. Since it says for any object that exists, there is a reason why it exists. Leibniz says we have a right to ask, "Why is there something rather than nothing?". He is saying that this question must have an answer. Well, this question has an answer only if there is an explanation or reason why the world exists.

P3: The world is a contingent thing, and for any contingent thing, in order to explain why it exists, you must look to things wholly distinct from it. So, if there really is a reason why the world exists, then since it's contingent, there must be something outside the world (something that is not a part of the world) that is the reason. And since this thing is the reason the world exists, the world is dependent upon it.  So, just from the fact that there is a reason why the world exists, we can infer that there is something outside the world that the world depends upon.

P3: This premise is true in virtue of the concepts involved (it's a conceptual truth, or an analytic truth). Since the world is defined as the aggregate of all the contingent things, anything outside the world cannot be contingent -- otherwise, it would have already been included in the aggregate of contingent things. Well, if something is not contingent, then it exists necessarily. Also, if the world does depend upon this thing for its existence, that is just to say that it would not have existed were it not for this thing. This just another way of saying that this thing created the universe. So, if this thing is outside the world and the world depends on it, then we can infer that it is necessarily existent and is the creator of the universe.

P6: (6) does not following from (5) as a matter of logic. Rather, it is a sort of abductive argument: the best explanation for the fact that there is this necessarily existing creator of the universe is that the thing is just God.

(e) Present and discuss the main objection to Leibniz's argument that we discussed in class.

To object to Leibniz's argument, one might deny PSR and hence deny P2.  Why think PSR is true for everything? All the examples we gave to support PSR were of smaller things. We didn't show that the principle applied to the aggregate of everything.

So this objection is say that there is just no reason why the universe exists. It is a brute fact. It's just the way it is, and that's all there is to say about it.

It would be nice if there were independent reasons to deny PSR. There may be: quantum mechanics. According to QM, nature is filled with events whose occurrence has no explanation whatever. If, for example, the nucleus of a radium decays at a certain time, there is no explanation whatever for its decaying at that time rather than some other time.  (Granted, this is not conclusive, because there are "hidden variable" interpretations of QM according to which there is an explanation, we just can't find it.)

(f) What do you think of Leibniz's argument? Does it provide a good reason to think God exists? Discuss.

<<<<This is my answer to 2(f).  Yours might be different.>>>>

Since PSR does seem pretty attractive to me, I think I might accept the first conclusion of the argument (line (5)).  But I'm not convinced that this thing has all the attributes that God is supposed to have, so I'm not sure I accept the inference to line (6).

3. (a) Present the First Argument from Evil (as we presented it in class).

First Argument from Evil
1. If God exists, then this world was created by an all-powerful, all-knowing, all-good being.
2. If this world was created by an all-powerful, all-knowing, all-good being, then this is the best of all possible worlds.
3. If this is the best of all possible worlds, then this world contains no evil.
4. This world contains some evil.
5. Therefore, God does not exist.

(b) Give the rationale for each premise.

P1: This follows from our definition of God, which say this:

God =df. the necessarily existing, all-powerful, all-knowing, all-good creator of the universe.

Given this definition, premise 1 is analytic.

P2: An all-knowing being would know every detail about every possible world, and would know which possible world is the best one. An all-powerful being would have the power to create any possible world he wants. An all-good being would prefer the best possible world, and would thus create the best possible world. Since this world is the one that was created, this world has got to be the best (if it was indeed created by an all-PKG being).

P3: If the world contained even the slightest about of evil, it would not be the best of all possible worlds. There would be a better possible world -- a world just like this one, but without the evil. The best possible world therefore cannot contain any evil at all.

P4: Just last September, many innocent people were unjustly killed in a horrific disaster. Many innocent children in Iraq die each month of sickness and starvation. Each day, women are raped in this country. Every year, fires, earthquakes, floods, hurricanes, and tornadoes cause the suffering and death of countless innocent people and animals. These things are bad. The world would be better if they didn't happen. They are evil. So, clearly, the world contains evil.

(c) Premise 3 of the argument is this:

3. If this is the best of all possible worlds, then this world contains no evil.

Discuss two reasons to think this premise is false.

(i) soul-building evils

The best world actually contains some evil, namely, "soul-building evil" -- evil that is necessary for us to be better people. The idea is that if we were to remove that evil, then the people in the world would have weaker characters. But the world is made better by having people with good characters. And the amount of good that's added by having these weaker characters exceeds the amount of bad that is necessary to bring them about.

Consider, for instance, the following traits of character: charity, compassion, bravery. These traits of character are good. But maybe it is logically impossible for these traits to exist with out evil. Exercising charity means helping someone who is not well-off who deserves to be better off (and this, the state of affairs of someone not being well-off who deserves to be well-off, is evil). Being compassionate means appreciating and having sympathy for someone's suffering (an evil). Being brave requires hanging in there in the face of hardship (an evil).

(ii) free will

It is argued by theists that there is another reason why evil might exist in the best world: the existence of free creatures like ourselves. It is claimed that freedom is good -- a world with free creatures is, all else being equal, better than a world without free creatures. But when there's free creatures, we run the risk of those creatures freely causing some evil. God is not responsible for this evil. And, though he could certainly prevent the evil we bring about, he could not prevent it without destroying our freedom (for to allow someone to make choices only if they are the ones you like is not to give him choices at all).

(d) How might premises 3 and 4 of the argument be revised to avoid these objections?

3´. If this is the best of all possible worlds, then the only evil this world contains is soul-building evil and evil caused by free agents.
4´. This world contains more than just soul-building evil and evil caused by free agents.

(e) What do you think of this revised argument? Is it sound? Does the Argument from Evil succeed in casting doubt on the existence of a perfect deity? Explain.

<<<<This is my answer to 3(e).  Yours might be different.>>>>

I think this new argument is sound. Here's why I think P4' is true. Consider the actual world -- the actual way things went. Hitler was born, and was responsible for the deaths and torture and forced labor of millions and millions of innocent men, women, and children -- people who didn't deserve this treatment.

Now imagine another world that God might have created. A world just like the actual world save one thing -- Hitler was never born. Call this world 'w1'. Surely, w1 contains plenty of evil to build souls and still contains plenty of free agents. It is incredible to suppose that w1, the world in which Hitler is never born, and all the innocent people get to live and be happy (and everything else stays the same), is worse than the actual way things went.

We can imagine the same sort of thing with respect to so-called "natural evils" as well, such the bubonic plague. There is another possible world -- call it 'w2' -- in which the plague doesn't occur, but everything else remains as it is. Removing the plague violates no one's free will (in fact, it adds to freedom, since sickness takes away people's freedom), and certainly the amount of soul-building that occurred as a result of the plague was not worth the cost. About one-third of the European population died agonizing deaths from the bubonic plague.

For these reasons, I think it is reasonable to conclude that there is no perfect deity.  Maybe there is some entity that deserves the name 'God', but this entity cannot be both all-powerful and all-good, since this is not the best of all possible worlds.