1. Midterm Review, Burden of Proof, Naturalistic Fallacy Sign In! Fake Quiz!/Review Poisoning the Well Burden of Proof Fallacies Naturalistic Fallacies For Next Time: Midterm!

2. Fake Quiz! If we don't act soon to remove the tax- exemptions enjoyed by non-profits then the recession will only deepen. What kind of claim is this? (a) subjective value claim (b) objective value claim (c) a policy claim (d) a valid claim

3. Fake Quiz! What, if anything, is wrong with B's response to A's argument? (A): We should not increase environmental regulation during a down economy because it would hurt business (B): What?! Don't you always agree with Libertarian policies anyway? You must be some kind of idiot. If we get rid of all environmental legislation, as you say, then we'll all die early deaths as a result of pollution and global warming

4. Fake Quiz! Two armed men were seen at a bank What is wrong with this claim? How would you fix the problems with the sentence?

5. Fake Quiz! Is the following argument valid or invalid? If it is valid, is it sound? 1. All puppies are cute 2. All cute things are small 3. :. All puppies are small

6. Fake Quiz! “In a study, a class of students was asked to estimate the date at which they would finish their thesis. They actually completed their thesis, on average, in 56 days. However, they predicted they would complete their thesis in 34 days. Indeed, even when asked when they might complete their thesis if "everything went as badly as it possibly could," the mean response was 49 days.” What Fallacy did these students just commit? Why?

7. Poisoning the Well If you contaminate a well with poison then nobody will want to drink from it We commit the fallacy of poisoning the well when we try to make a source seem unattractive to others as a way of persuading them to reject a claim Well poisoning works because of negativity bias

8. Poisoning the Well Fallacies We have already studied many ways in which we sometimes (fallaciously) discredit sources in order to make a claim seem less attractive: Ad Hominem family Genetic Fallacy Straw Man But there are other ways to poison the well that go beyond these other fallacies Denying that someone is linked with outrageous charges often creates such a link due to negativity bias

9. Poisoning the Well: Example “Republican White House hopeful [candidate] has declined to say whether he thinks President Barack Obama was born in the United States, all but embracing a debunked controversy known as “birtherism.” The [state] governor told Parade magazine in an interview that he had “no reason to think” Obama was not born in the United States but said “I don’t have a definitive answer” about whether that was the case.”* Regardless of the candidate's other merits or demerits, this is a classic example of Poisoning the Well without resorting to ad hominem or a strawman *Agence France-Presse (AFP), October 26 th 2011

10. Burden of Proof Fallacies Burden of proof: a term describing whomever has the responsibility for advancing an argument Typically it is clear who has the burden of proof in an argument or counter-argument The person advancing or stating a claim normally has the burden of proof to support the claim unless the claim is widely recognized as having been proved or otherwise shown to be true Some fallacies work by shifting the burden of proof

11. Who has the burden? There are few rules to determine who has the burden of proof in an argument but we can offer a couple of guidelines: 1. Inherent credibility: if a claim has widespread and strong inherent credibility then the burden of proof lies on anyone who rejects the claim  Example: (A): We can track the evolution of snail species for hundreds of millions of years  (B): Wait, you haven't yet supported evolution 2. Affirming/Rejecting: the burden of proof rests on a person supporting a claim. If a claim has already been supported then the burden (non-fallaciously) shifts to those who reject the argument

12. Who has the burden?: example (A): I saw ghost last night! I think it was the ghost of my beloved Chihuahua Pepe. (B): Really? I don't believe you. In this example does (A) have the burden of proof to provide an argument in favor of the claim or does (B) have the burden of showing that it is false? Why?

13. Who has the burden?: Example (again) (A): I saw ghost last night! I think it was the ghost of my beloved Chihuahua Pepe. When I woke up there was a pile of his favorite dog food by my bed and his old collar was there too, by the pile. (B): Really? I don't believe you. Who has the burden of proof in this case? Why?

14. Burden Shifting Fallacy We commit a burden shifting fallacy whenever we improperly shift the burden of proof during a disagreement (A): There is no evidence that ghosts don't exist. Until you prove that they don't then we should think they do exist (B): What? In this case A is fallaciously shifting the burden of proof on to B to prove a claim false for which no argument has yet been given A's argument, in effect, is that we should assume that until the claim is proven false that it is therefore true

15. Naturalistic Fallacies Naturalistic Fallacies involve any arguments that appeal to nature to tell us what is good or bad In its most common form the naturalistic fallacy implies that natural things are good and unnatural things are bad This is a form of begging the question since “natural” is both vague and ambiguous

16. Naturalistic Fallacy It is unclear how to understand what is natural or unnatural Naturalness is ambiguous:  Naturalness contrasts things done by humans with all other things  Naturalness can mean 'part of the natural world' According to the first definition all human creations are unnatural whereas on the second definition everything humans do is natural “Natural” is also a vague concept: while a computer is clearly unnatural and dirt is clearly natural, what about marriage?

17. Example Incest, for example, is often criticized as an unnatural practice but this is hard to understand What sense of natural is implied? Since some human behaviors are presumably not condemned we can assume it means 'a part of the natural order' Many species reproduce asexually, is this a form of natural incest? Many other species routinely reproduce with direct siblings It is a mistake to assume both that there is an obvious sense of naturalness and that naturalness = goodness

18. Naturalistic Fallacy and the Is/Ought Gap During week 2 we said that value claims and claims of fact can become problematic during arguments Claims of fact tell us how the world is Claims of value tell us how the world ought to be The naturalistic fallacy, aside from its problems with vagueness and ambiguity, is also problematic because it confuses these two kinds of claims You cannot have an argument that consists solely of claims of fact with a conclusion that is a claim of value

19. Example 1. Most people have historically lived under dictatorships or monarchies 2. Many people in the world today live under dictatorships or monarchies 3. :. We should institute a dictatorship or monarchy To fix this argument we need a claim that links facts and values: “if most people have done something then we ought to do it.” When we fix the fallacious argument by adding the fact/value premise then the original problem (why it is a mistake) is clear The fact/value claim requires an argument of its own

20. For Next Time Study for the midterm! I will accept questions via e-mail until the sun goes down on Thursday