Saturday can't get here fast enough. Until then, this will do.
(Credit goes to Nevin O'Donnell. See? Always cite your source.)
Thursday, August 31, 2006
Anselm's Ontological Argument
(or, Missed It By That Much)
So there it is. Proof that God exists (in only 9 steps!). See? Philosophy can be pretty easy sometimes.
I won't rehash the entire argument here-- you've got it in your notes, and we'll review it tomorrow if we have to-- but I wanted to point out a couple of its important features. First of all, the argument is deductively valid. As Ramsey said, once you grant the first three premises, the game is over. Which means, the only way the argument can be unsuccessful is if one of the first three premises is false. A good criticism of the argument, then, must call into question one of those premises. To review:
1. God exists in the understanding.
2. God is a possible being.
3. If something exists only in the understanding and could have existed in reality, then it could have been greater than it is.
Questions to consider:
For those who think the argument doesn't work, which of the above premises is false?
Is Anselm's definition of "God" any good? Does it matter for his argument if it isn't?
Does Gaulimo's "Perfect Island" criticism hold any water?
Is it proper to say that "existence" is a property held by an object?
Or can the argument be attacked in an entirely different way?
Big concepts. Big ideas. Big questions. Big fun. It's on.
I won't rehash the entire argument here-- you've got it in your notes, and we'll review it tomorrow if we have to-- but I wanted to point out a couple of its important features. First of all, the argument is deductively valid. As Ramsey said, once you grant the first three premises, the game is over. Which means, the only way the argument can be unsuccessful is if one of the first three premises is false. A good criticism of the argument, then, must call into question one of those premises. To review:
1. God exists in the understanding.
2. God is a possible being.
3. If something exists only in the understanding and could have existed in reality, then it could have been greater than it is.
Questions to consider:
For those who think the argument doesn't work, which of the above premises is false?
Is Anselm's definition of "God" any good? Does it matter for his argument if it isn't?
Does Gaulimo's "Perfect Island" criticism hold any water?
Is it proper to say that "existence" is a property held by an object?
Or can the argument be attacked in an entirely different way?
Big concepts. Big ideas. Big questions. Big fun. It's on.
Wednesday, August 30, 2006
Argument Wrap-Up, Religion Intro.
Just wanted to touch on a couple of the points Ramsey made yesterday. He was discussing common falacies in philosophical argument. Among those fallacies, as I pointed out in at least one of the discussion sections, is a misuse of the modus ponens or modus tollens argument form. If our first premise is a conditional (an "if-then" statement) and the second premise confirms the "then" part (the consequent, if you want to get technical), we cannot deduce anything from the argument. Likewise, if the second premise denies the "if" part (the antecedent), then we cannot deduce anything. Watch out for those two.
Probably the most common fallacy you will run across is begging the question. This occurs in an argument when the conclusion that is to be established is essentially stated as one of the argument's premises. Probably the simplest example of begging the question would be something like the following:
Nemo is a fish.
Nemo is a fish.
Note that this argument is perfectly valid [why?]. And if the premise is true, the argument is sound as well. But it still is not considered a good argument. The whole purpose of deductive argument is to use established facts to extend our knowledge to an entirely new conclusion. When we include the conclusion in the premises of our arguments, we are not using the argumentative structure as it was intended. And at the very least, our argument will be completely discounted by anyone who doesn't already agree with us.
(Note also that the phrase "that begs the question..." is often used in everyday language to mean something else. Like, when Notre Dame beats Georgia Tech this weekend, a Notre Dame hater might say, "Well that begs the question of whether Tech is any good or not." No, it doesn't. The next time a friend says this to you, you can respond by saying, "Actually, begging the question has a specific meaning regarding the structure of philosophical argument. What you mean to say is that ND's victory prompts the question of whether or not Tech is any good. Be more careful with your language next time." Your friend will look at you like you're an idiot, but you'll know better...)
On to religion. The first thing to keep in mind during this section of the course is that religious questions have real answers. "Is there a God?" The answer is either yes or no. "God exists for me, but not for you" is a copout, and is probably incoherent. "Was Mohammed a prophet?" He either was or he wasn't. Agreeing to disagree is fine and dandy, but it doesn't mean that one of you isn't wrong.
The second point to consider is the importance of arguing for particular religious beliefs. There is nothing wrong with scruitinizing religious beliefs. Since we're talking about actual facts about the world (as opposed to subjective feelings), all the tools of argument are at our disposal. Moreover, philosophical argument has been part and parcel of most religious traditions for a very long time. By taking part in that tradition, hopefully we can come to a better understanding of where some aspects of our own religious faiths come from.
(Now, whether or not the arguments we encounter are completely convincing, or whether it's even possible to establish religious claims through a priori argument, is another question altogether. Hmm....)
On to St. Anselm.
Probably the most common fallacy you will run across is begging the question. This occurs in an argument when the conclusion that is to be established is essentially stated as one of the argument's premises. Probably the simplest example of begging the question would be something like the following:
Nemo is a fish.
Nemo is a fish.
Note that this argument is perfectly valid [why?]. And if the premise is true, the argument is sound as well. But it still is not considered a good argument. The whole purpose of deductive argument is to use established facts to extend our knowledge to an entirely new conclusion. When we include the conclusion in the premises of our arguments, we are not using the argumentative structure as it was intended. And at the very least, our argument will be completely discounted by anyone who doesn't already agree with us.
(Note also that the phrase "that begs the question..." is often used in everyday language to mean something else. Like, when Notre Dame beats Georgia Tech this weekend, a Notre Dame hater might say, "Well that begs the question of whether Tech is any good or not." No, it doesn't. The next time a friend says this to you, you can respond by saying, "Actually, begging the question has a specific meaning regarding the structure of philosophical argument. What you mean to say is that ND's victory prompts the question of whether or not Tech is any good. Be more careful with your language next time." Your friend will look at you like you're an idiot, but you'll know better...)
On to religion. The first thing to keep in mind during this section of the course is that religious questions have real answers. "Is there a God?" The answer is either yes or no. "God exists for me, but not for you" is a copout, and is probably incoherent. "Was Mohammed a prophet?" He either was or he wasn't. Agreeing to disagree is fine and dandy, but it doesn't mean that one of you isn't wrong.
The second point to consider is the importance of arguing for particular religious beliefs. There is nothing wrong with scruitinizing religious beliefs. Since we're talking about actual facts about the world (as opposed to subjective feelings), all the tools of argument are at our disposal. Moreover, philosophical argument has been part and parcel of most religious traditions for a very long time. By taking part in that tradition, hopefully we can come to a better understanding of where some aspects of our own religious faiths come from.
(Now, whether or not the arguments we encounter are completely convincing, or whether it's even possible to establish religious claims through a priori argument, is another question altogether. Hmm....)
On to St. Anselm.
Friday, August 25, 2006
The Nuts and Bolts of Arguments
This will be just a quick review of the structure and vocabulary of argumentation. Briefly, a philosophical argument is a series of premises logically leading to a conclusion. When considering an argument, we judge it based on the relationships the premises have to the sub-conclusions and, ultimately, the argument's final conclusion.
Arguments are neither true nor false. Instead, arguments are either valid or invalid. A valid argument is one for which there is no way that all the premises could be true and yet the conclusion be false. Put another way, in a valid argument the truth of the premises guarantees the truth of the conclusion. (Note: this latter definition of validity, while a bit easier to remember and understand, could be misconstrued to mean that valid arguments have true premises. This is not the case. It might be more precise to say that, in a valid argument, the truth of the premises would guarantee the truth of the conclusion-- if they were in fact true.)
The three most important valid argument forms are categorical syllogism, modus ponens, and modus tollens. Each can be illustrated with an example from class.
Notice, for each example, that the sentences plugged into the scheme are irrelevant for evaluating the validity of the argument. In fact, we could plug in nonsensical words and it would not affect the validity:
All gleebs are sproos.
Arthur is a gleeb.
Arthur is a sproo.
Alternatively, we could plug in absurd premises:
If the aliens visited the Taj Mahal, then gas costs 50 cents a gallon.
The aliens visited the Taj Mahal.
Gas costs 50 cents a gallon.
When we evaluate an argument, we forget everything we know about the world. We take the premises as given. If the conclusion automatically follows, the argument is valid.
Any questions?
Arguments are neither true nor false. Instead, arguments are either valid or invalid. A valid argument is one for which there is no way that all the premises could be true and yet the conclusion be false. Put another way, in a valid argument the truth of the premises guarantees the truth of the conclusion. (Note: this latter definition of validity, while a bit easier to remember and understand, could be misconstrued to mean that valid arguments have true premises. This is not the case. It might be more precise to say that, in a valid argument, the truth of the premises would guarantee the truth of the conclusion-- if they were in fact true.)
The three most important valid argument forms are categorical syllogism, modus ponens, and modus tollens. Each can be illustrated with an example from class.
| Argument Type | Argument Form | Example |
| Categorical Syllogism | All A's are B's x is an A x is a B | All men are mortal Socrates is a man. Socrates is mortal. |
| Modus Ponens | If p, then q. p q | If Nemo is a fish, then Nemo can swim. Nemo is a fish. Nemo can swim. |
| Modus Tollens | If p, then q. not q not p | If Nemo is a fish, then Nemo can swim. Nemo cannot swim. Nemo is not a fish. |
Notice, for each example, that the sentences plugged into the scheme are irrelevant for evaluating the validity of the argument. In fact, we could plug in nonsensical words and it would not affect the validity:
All gleebs are sproos.
Arthur is a gleeb.
Arthur is a sproo.
Alternatively, we could plug in absurd premises:
If the aliens visited the Taj Mahal, then gas costs 50 cents a gallon.
The aliens visited the Taj Mahal.
Gas costs 50 cents a gallon.
When we evaluate an argument, we forget everything we know about the world. We take the premises as given. If the conclusion automatically follows, the argument is valid.
Any questions?
Thursday, August 24, 2006
Welcome to PHIL 10100
You did it. You made it to Notre Dame. You've been waiting for this your whole life. And the first thing they do is plop you into a giant Philosophy lecture and start bombarding you with bizarre and unfamiliar issues. You didn't sign up for this! What does any of this have to do with learning to be an engineer, or a doctor, or an accountant?
Everything and nothing. That's the beauty of it.
As Ramsey said the other day, philosophy is about thinking very carefully about abstract issues. The "thinking very carefully" part is what is going to aid you in the long run, whatever career you end up taking. The "abstract issues" part is the fun little bonus. While it seems that the questions we'll cover have no bearing on everyday life, they're actually some of the most fundamental questions we can ever ask. And this might be the first time in your life that you have time to think about them. In fact, college might be the only time in your life that you get to think about them. So take advantage while you're here-- philosophy can be a lot of fun if you let it.
To that end, the course is organized around the questions and issues themselves, rather than around any particular thinkers' thoughts on the issues. While the classic thinkers-- your Platos, your Berkeleys, your Kants-- are certainly important, you can only appreciate their contributions if you are already somewhat familiar with the material. The goal of the Intro course is to introduce the questions, and to get you talking intelligently about the issues, without bogging you down with specific historical points of view. Memorization ain't fun. Thinking for yourself is.
And even more fun is arguing for your own point of view. That's what this place is for-- to extend the discussion outside of class. After all, if this is your one chance in life to get to think about these abstract issues, fifty minutes a week is not going to cut it. I'll probably be posting a little something after every lecture, and the comments section is yours. (Just stick to philosophy, unless my post isn't about philosophy. Expect a football post or two-- I just can't help myself). We're open 24 hours a day. The dresscode is casual. Have at it.
Everything and nothing. That's the beauty of it.
As Ramsey said the other day, philosophy is about thinking very carefully about abstract issues. The "thinking very carefully" part is what is going to aid you in the long run, whatever career you end up taking. The "abstract issues" part is the fun little bonus. While it seems that the questions we'll cover have no bearing on everyday life, they're actually some of the most fundamental questions we can ever ask. And this might be the first time in your life that you have time to think about them. In fact, college might be the only time in your life that you get to think about them. So take advantage while you're here-- philosophy can be a lot of fun if you let it.
To that end, the course is organized around the questions and issues themselves, rather than around any particular thinkers' thoughts on the issues. While the classic thinkers-- your Platos, your Berkeleys, your Kants-- are certainly important, you can only appreciate their contributions if you are already somewhat familiar with the material. The goal of the Intro course is to introduce the questions, and to get you talking intelligently about the issues, without bogging you down with specific historical points of view. Memorization ain't fun. Thinking for yourself is.
And even more fun is arguing for your own point of view. That's what this place is for-- to extend the discussion outside of class. After all, if this is your one chance in life to get to think about these abstract issues, fifty minutes a week is not going to cut it. I'll probably be posting a little something after every lecture, and the comments section is yours. (Just stick to philosophy, unless my post isn't about philosophy. Expect a football post or two-- I just can't help myself). We're open 24 hours a day. The dresscode is casual. Have at it.
Subscribe to:
Posts (Atom)