1. Doing Metaphysics: Questions, Claims, and Proofs

2. “That which I may not have known-through-seeing in no way I imagine myself to have known-through-seeing.” -Socrates, in Plato’s Apology Often paraphrased: “I know that I know nothing”

3. But First, a Joke…

4. Reducto ad… um, Harry Potter? ‘… what about the stone, Mr Lovegood? The thing you call the Resurrection Stone?’ ‘What of it?’ ‘Well, how can that be real?’ ‘Prove that it is not,’ said Xenophilius. Hermione looked outraged. ‘But that’s — I’m sorry, but that’s completely ridiculous! How can I possibly provide it doesn’t exist? Do you expect me to get hold of — of all the pebbles in the world, and test them? I mean, you could claim that anything’s real if the only basis for believing in it is that nobody’s proved it doesn’t exist!

5. Partner Activity-Answering the Big Questions 1. Must anything that exists stand in some relation to something else? 2. Can there be things that exist that are not in time? 3. What are numbers? 4. Can there be things that are in principle unobservable? 5. Why is there something, rather than nothing? 6. Is time real, or an illusion? 7. Could a cause and its effect be simultaneous? 8. Does the physical universe depend upon the existence of an immaterial creator? 9. Is the self a bundle of experiences? 10. Are humans free?

6. Term to remember: Deductive Reasoning: To move from the general to the specific. Ex: All men are Mortal. Socrates is a man, therefore Socrates is mortal. This type of deductive phrase is known as a syllogism

7. Now try reducing to a Contradiction  Logical Form of reduction Ad Absurdum (proof by contradiction):  Assume P is true.  From this assumption, deduce that Q is true.  Also deduce that Q is false.  Thus, P implies both Q and not Q (a contradiction, which is necessarily false).  Therefore, P itself must be false.

8. Unclear? Here is an Example I am going into surgery tomorrow so please pray for me. If enough people pray for me, God will protect me from harm and see to it that I have a successful surgery and speedy recovery. Explanation: We first assume the premise is true: if “enough” people prayed to God for her successful surgery and speedy recovery, then God would make it so. From this, we can deduce that God responds to popular opinion. However, if God simply granted prayers based on popularity contests, that would be both unjust and absurd. Since God cannot be unjust, then he cannot both respond to popularity and not respond to popularity, the claim is absurd, and thus false.

9. Still Unclear? Well lets try this again… If everyone lived his or her life exactly like Jesus lived his life, the world would be a beautiful place! Explanation: We first assume the premise is true: if everyone lived his or her life like Jesus lived his, the world would be a beautiful place. If this were true, we would have 7 billion people on this earth roaming from town to town, living off the charity of others, preaching about God (with nobody listening). Without anyone creating wealth, there would be nobody to get charity from -- there would just be 7 billion people all trying to tell each other about God. After a few weeks, everyone would eventually starve and die. This world might be a beautiful place for the vultures and maggots feeding on all the Jesus wannabes, but far from a beautiful world from a human perspective. Since the world cannot be both a beautiful place and a horrible place, the proposition is false.

10. Lets try it! Remember:  Assume P is true.  From this assumption, deduce that Q is true.  Also deduce that Q is false.  Thus, P implies both Q and not Q (a contradiction, which is necessarily false).  Therefore, P itself must be false.