BS

Here's the video of Jon Stewart interviewing Harry Frankfurt about his book On Bullshit (which you can read online for free here).



What do you think? Is not caring about whether you're telling the truth worse than deliberately lying?

Homework #3

Homework #3 is due at the beginning of class on Monday, May 10th. Your assignment is to choose an ad (on TV or from a magazine or wherever) and evaluate it from a logic & reasoning perspective.

• First, very briefly explain the argument that the ad offers to sell its product.
• Then, list and explain the mistakes in reasoning that the ad commits.
• Then, list and explain the psychological ploys the ad uses (what psychological impediments does the ad try to exploit?).
• Attach (if it's from a newspaper or magazine) or briefly explain the ad.
  

Intellectual Humility

I think there’s an important connection between intellectual honesty and humility. A simple goal of this class is to get us all to recognize what counts as good evidence and what counts as bad evidence for a claim. I think we've gotten pretty good at this so far. But this doesn’t guarantee that we’ll care about the difference once we figure it out.

Getting us to care is the real goal. We should care about good evidence. We should care about evidence and arguments because they get us closer to the truth. When we judge an argument to be overall good, THE POWER OF LOGIC COMPELS US to believe the conclusion. If we are presented with decent evidence for some claim, but still stubbornly disagree with this claim for no strong reason, we are just being irrational. Worse, we’re effectively saying that the truth doesn’t matter to us.

Instead of resisting, we should be open-minded. We should be willing to challenge ourselves--seriously challenge ourselves--and allow new evidence change our current beliefs if it warrants it. We should be open to the possibility that we’ve currently gotten something wrong. This is how comedian Todd Glass puts it:

Here are the first two paragraphs of an interesting article on this:

Last week, I jokingly asked a health club acquaintance whether he would change his mind about his choice for president if presented with sufficient facts that contradicted his present beliefs. He responded with utter confidence. “Absolutely not,” he said. “No new facts will change my mind because I know that these facts are correct.”

I was floored. In his brief rebuttal, he blindly demonstrated overconfidence in his own ideas and the inability to consider how new facts might alter a presently cherished opinion. Worse, he seemed unaware of how irrational his response might appear to others. It’s clear, I thought, that carefully constructed arguments and presentation of irrefutable evidence will not change this man’s mind.

Ironically, having extreme confidence in oneself is often a sign of ignorance. Remember, in many cases, such stubborn certainty is unwarranted.

Metacognition

There's a name for all the studying of our natural thinking styles we've been doing in class lately: metacognition. When we think about the ways we think, we can vastly improve our learning abilities. This is what the Owning Our Ignorance club is about.

I think this is the most valuable concept we're learning all semester. So if you read any links, I hope it's these two:

• How Doctors Can Improve By Thinking About Thinking
  
• The Importance of Metacognition

Practical Advice

How can we counteract these cognitive biases we're learning about? One big point is to own our fallibility. Awareness of our limits and biases should lead us to lower our degree of confidence in our beliefs. Simply put, we should admit (and sincerely believe) that there's a real chance that we're wrong.

Here are two other big, simple points I think make for some great practical advice:

1. Actively seek out sources that you disagree with. We tend to surround ourselves with like-minded people and consume like-minded media. This hurts our chances of discovering that we've made a mistake. In effect, it puts up a wall of rationalization around our preexisting beliefs to protect them from any countervailing evidence.
2. When we do check out our opponents, it tends to be the obviously fallacious straw men rather than sophisticated sources that could legitimately challenge our beliefs. But this is bad! We should focus on the best points in the arguments against what you believe. Our opponents' good points are worth more attention than their obviously bad points. Yet we often focus on their mistakes rather than the reasons that hurt our case the most.

Let's All Nonconform Together

If you like these links, I'll let you in my exclusive club:

• On the influence of your in-groups and the formation of your identity: "If you want to set yourself apart from other people, you have to do things that are arbitrary, and believe things that are false." (from Paul Graham's "Lies We Tell Our Kids.")
  
• Here's a summary of two recent studies which suggest that partisan mindset stems from a feeling of moral superiority.
• Here's that poll showing the Republican-Democrat switcharoo regarding their opinion of Fed Chairman Ben Bernanke when the executive office changed parties.
  
• Our political loyalties also influence our view on the economy.
  
• Here's an article about a cool study on the relationship between risk and provincialism.
• Conformity hurts the advancement of science.

Status Quo Bias

Lazy, inert humans:

• If it already exists, we assume it's good.
• Our mind works like a computer that depends on cached responses to thoughtlessly complete common patterns.
  
• NYU psychologist John Jost does a lot of work on system justification theory: our tendency to unconsciously rationalize the status quo, especially unjust social institutions. Scarily, those of us oppressed by such institutions have a stronger tendency to justify their existence.
• Jost has a new book on this stuff. Here's a video dialogue about his research:
  

Wished Pots Never Boil

Here is a hodgepodge of links on some psychological impediments we're discussing recently:

• If you're a fan of The Secret, you should beware that it's basic message is wishful thinking run amok.
• Teachers have biases, too: we're self-serving and play favorites.
• Why don't we give more aid to those in need? Psychological impediments are at least partly to blame.
• Why do we believe medical myths (like "vitamin C cures the common cold," or "you should drink 8 glasses of water a day")? Psychological impediments, of course!
  

Second-Hand News

Angelo heard it through the grapevine:

The Smart Bias

Oddly, the I'M-SPECIAL-ism bias seems to increase the more intelligent you are. Studies suggest that the smarter and more experienced you are, the more overconfident you're likely to become. In particular, we seem to believe that our intelligence makes us immune to biases. But that's just not true! The philosopher Nigel Warburton puts it nicely:

“Many of us would like to believe that intellect banishes prejudice. Sadly, this is itself a prejudice.”

No, You're Not

One of my favorite topics is I'M-SPECIAL-ism. Psychological research has repeatedly shown that most Americans overestimate their own abilities. This is one of the biggest hurdles to proper reasoning: the natural tendency to think that we're more unique--smarter, or more powerful, or prettier, or whatever--than we really are.

You've probably noticed that one of my favorite blogs is Overcoming Bias. Their mission statement is sublimely anti-I'M-SPECIAL-ist:

"How can we better believe what is true? While it is of course useful to seek and study relevant information, our minds are full of natural tendencies to bias our beliefs via overconfidence, wishful thinking, and so on. Worse, our minds seem to have a natural tendency to convince us that we are aware of and have adequately corrected for such biases, when we have done no such thing."

This may sound insulting, but one of the goals of this class is getting us to recognize that we're not as smart as we think we are. All of us. You. Me! That one. You again. Me again!

So I hope you'll join the campaign to end I'M-SPECIAL-ism.

The Importance of Being Stochastic

Statistical reasoning is incredibly important. The vast majority of advancements in human knowledge (all sciences, social sciences, medicine, engineering...) is the result of using some kind of math. If I had to recommend one other course that could improve your ability to learn in general, it'd be Statistics.

Anyway, a few links:

• I brought up this article before, but I'll mention it again: most of us are pretty bad at statistical reasoning.
• That radio show I love recently devoted an entire episode to probability:
  
  
• Here's a review of a decent book (The Drunkard's Walk: How Randomness Rules Our Lives) on our tendency to misinterpret randomness as if it's an intentional pattern.
• This ability to see patterns where there are none may explain why so many of us believe in god (see section 5 in particular).
• What was that infinite monkey typewriter thing we were talking about in class?
• What's up with that recent recommendation that routine screenings for breast cancer should wait to your 50s rather than 40s? Math helps explain it.
• Another radio show I love ran a great 2-part series on the screening for diseases called "You Are Pre-Diseased":
  

  Listen to Episode 1

  Listen to Episode 2

• Statistics in sports is all the rage lately. It can justify counterintuitive decisions, like going for it instead of punting on 4th down... though don't expect the fans to buy that fancy math learnin'.
  

Quiz #2

Quiz #2 will be held at the beginning of class on Wednesday, April 21st. It will last 25 minutes, and is worth 7.5% of your overall grade. The quiz is on everything we've discussed since the midterm:

• Fallacies (starting with appeal to ignorance to the end of chapter 5)
• Psychological Impediments (chapter 4)

The quiz will contain a mix of short answer questions and arguments that contain fallacies.

The Conspiracy Bug

Here's an article on a 9/11 conspiracy physicist that brings up a number of issues we're discussing in class (specifically appealing to authority and confirmation bias). I've quoted an excerpt of the relevant section on the lone-wolf semi-expert (physicist) versus the overwhelming consensus of more relevant experts (structural engineers):

While there are a handful of Web sites that seek to debunk the claims of Mr. Jones and others in the movement, most mainstream scientists, in fact, have not seen fit to engage them.

"There's nothing to debunk," says Zdenek P. Bazant, a professor of civil and environmental engineering at Northwestern University and the author of the first peer-reviewed paper on the World Trade Center collapses.

"It's a non-issue," says Sivaraj Shyam-Sunder, a lead investigator for the National Institute of Standards and Technology's study of the collapses.

Ross B. Corotis, a professor of civil engineering at the University of Colorado at Boulder and a member of the editorial board at the journal Structural Safety, says that most engineers are pretty settled on what happened at the World Trade Center. "There's not really disagreement as to what happened for 99 percent of the details," he says.

And one more excerpt on reasons to be skeptical of conspiracy theories in general:

One of the most common intuitive problems people have with conspiracy theories is that they require positing such complicated webs of secret actions. If the twin towers fell in a carefully orchestrated demolition shortly after being hit by planes, who set the charges? Who did the planning? And how could hundreds, if not thousands of people complicit in the murder of their own countrymen keep quiet? Usually, Occam's razor intervenes.

Another common problem with conspiracy theories is that they tend to impute cartoonish motives to "them" — the elites who operate in the shadows. The end result often feels like a heavily plotted movie whose characters do not ring true.

Then there are other cognitive Do Not Enter signs: When history ceases to resemble a train of conflicts and ambiguities and becomes instead a series of disinformation campaigns, you sense that a basic self-correcting mechanism of thought has been disabled. A bridge is out, and paranoia yawns below.

Rationalizing Away from the Truth

A big worry that the confirmation and disconfirmation biases raise is the difficulty of figuring out what counts as successful, open-minded reasoning, versus what amounts to after-the-fact rationalization of preexisting beliefs. Here are some links on our tendency to rationalize rather than reason:

• Recent moral psychology suggests that we often simply rationalize our snap moral judgments. (Or worse: we actually undercut our snap judgments to defend whatever we want to do.)
• The great public radio show Radio Lab devoted an entire show to the psychology of our moral decision-making:
  
  
• Humans' judge-first, rationalize-later approach stems in part from the two competing decision-making styles inside our heads.
• For more on the dual aspects of our minds, I strongly recommend reading one of the best philosophy papers of 2008: "Alief and Belief" by Tamar Gendler.
  
• Here's a video dialogue between Gendler and her colleague (psychologist Paul Bloom) on her work:

Homework #2

Just a reminder that homework #2 is due at the beginning of class on Monday, November 2nd. The assignment is to determine the fallacy (if there is one) in each of the arguments from #1 (a through t) of exercise 5-3 on pages 150-151 of our textbook.

All Email Forwards Are False?

I got the following email last week:

-------------- Forwarded Message: --------------
From: Papa Landis
To: Mama Landis; Me; My Twin; My Older Brother; My Older Sister
Subject: Fw: Really Important After Sunday's Vote

-------------- Forwarded Message: --------------
Forwarded by Colleague
To: Papa Landis [and dozens more]

-------------- Forwarded Message: --------------
From: Friend of Colleague
To: [Dozens]

.
.
.

From: Gilbert Turrentine (original source?)
Subject: Really Important After Sunday's Vote

I have passed it onto over 100~~~please pass on to how ever many you can.

Really Important After Sunday's Vote
It may well be time for this approach; it's tough to argue against the principle! This will take less than thirty seconds to read. If you agree, please pass it on.

An idea whose time has come
For too long we have been too complacent about the workings of Congress. Many citizens had no idea that members of Congress could retire with the same pay after only one term, that they didn't pay into Social Security, that they specifically exempted themselves from many of the laws they have passed (such as being exempt from any fear of prosecution for sexual harassment) while ordinary citizens must live under those laws. The latest is to exempt themselves from the Healthcare Reform that is being considered...in all of its forms. Somehow, that doesn't seem logical. We do not have an elite that is above the law. I truly don't care if they are Democrat, Republican, Independent or whatever. The self-serving must stop. This is a good way to do that. It is an idea whose time has come.
...

Proposed 28th Amendment to the United States Constitution
"Congress shall make no law that applies to the citizens of the United States that does not apply equally to the Senators and/or Representatives; and, Congress shall make no law that applies to the Senators and/or Representatives that does not apply equally to the citizens of the United States."

Here was my response:

From: Me
To: Papa Landis
Subject: Re: Really Important After Sunday's Vote

The claims about Congress aren't true:
http://www.factcheck.org/2010/01/lawmaker-loopholes

His response to me:

From: Papa Landis
To: Me
Subject: Re: Really Important After Sunday's Vote

OK, thanks for that.

Hearsay, You Say?

-via GraphJam

-via xkcd

More to Forget

Here's more on the less of memory:

• Here's an overview on the way our memory is faulty by psychologist Gary Marcus. He's written a book called Kluge: The Haphazard Construction of the Human Mind.
  
• Even strong "flashbulb memories" like what you were doing on 9/11 are not very accurate.
• One leading expert on memory is psychologist Elizabeth Loftus. Here is a pair of articles that summarize her research on false memories, and here's a video of her presenting on it.

Filling in Memory

Here's a section (pages 78-80) from psychologist Dan Gilbert's great book Stumbling on Happiness about how memory works:



The preview cuts off at the bottom of page 80. Here's the rest from that section:

"...reading the words you saw. But in this case, your brain was tricked by the fact that the gist word--the key word, the essential word--was not actually on the list. When your brain rewove the tapestry of your experience, it mistakenly included a word that was implied by the gist but that had not actually appeared, just as volunteers in the previous study mistakenly included a stop sign that was implied by the question they had been asked but that had not actually appeared in the slides they saw.

"This experiment has ben done dozens of times with dozens of different word lists, and these studies have revealed two surprising findings. First, people do not vaguely recall seeing the gist word and they do not simply guess that they saw the gist word. Rather, they vividly remember seeing it and they feel completely confident that it appeared. Second, this phenomenon happens even when people are warned about it beforehand. Knowing that a researcher is trying to trick you into falsely recalling the appearance of a gist word does not stop that false recollection from happening."

Too many words, Sean! Can't you just put up a video? You better make it funny, too!

Fine. Here's Dan Gilbert on The Colbert Report:

Direct Experience

Here's two videos on stuff we've been talking about in class lately. First, watch this:


Next, watch this:


Finally, here's an article on this issue. Still trust your direct experience?

Deoderant Gender Norms

If you don't buy these products, you're being unnatural:

Ask Friends... Old Friends

Here's a case for more deference in our lives from one of my favorite websites:

• Often times, our friends know more about us than we do.
• While talking to your friends, you might want to ask more about them. It turns out that they're less like us than we might think.
• Also, consider listening to advice from older people. We're not as different from them as we think.
  

Extra Credit: Guest Speaker

The Owning Our Ignorance club is sponsoring a guest speaker to talk about god and suffering! Here are the details:

• Bryan Frances, Fordham University Philosophy Professor
• “An Adequate Theistic Response to the Problem of Gratuitous Evil?”
• Wednesday, April 7th
  
• 2:00 p.m.
• Madison 210
• Join the Facebook Event!

I'm offering an extra credit assignment: you can attend and write up a short paper on your reaction to the talk. The assignment is worth up to 20 points added to your final grade (out of 1,000).

Penguin Digestion Experts?!? You Bet!

So you didn't believe me when I said that there are experts on the subject of penguin digestion? Oh, you did? Fine, well, I'll prove it to you, anyway. Here are some academic articles on the topic:

• Adjustments of gastric pH, motility and temperature during long-term preservation of stomach contents in free-ranging incubating king penguins from a 2004 issue of Journal of Experimental Biology
  
• Feeding Behavior of Free-Ranging King Penguins (Aptenodytes Patagonicus) from a 1994 issue of Ecology

Of course, no list would be complete without the often-cited, groundbreaking 1985 Ornis Scandinavica article:

• Differential Digestion of Fish and Squid in Jackass Penguins Spheniscus demersus

Perhaps my favorite, though, is the following:

• Pressures produced when penguins pooh—calculations on avian defaecation from a 2003 issue of Polar Biology
  

If any of these articles are above your head (I think they're all above mine!), you might like this, uh, simpler video demonstration of penguin digestion.

An Expert for Every Cause

Looking for links on appealing to authority? This is your post! First, here's an interesting article on a great question: How are those of us who aren't experts supposed to figure out the truth about stuff that requires expertise?

Not all alleged experts are actual experts. Here's a method to tell which experts are phonies (this article was originally published in the Chronicle of Higher Education).

It's important to check whether the person making an appeal to authority really knows who the authority is. That's why we should beware of claims that begin with "Studies show..."

And here's a Saturday Night Live sketch in which Christopher Walken completely flunks the competence test.

Possible Paper Articles

Here are some links to a variety of articles you could use for your paper on explaining and evaluating an article's argument. I strongly recommend using one of these articles, since most contain bad arguments:

1. Down With Facebook!: it's so stupid
2. Do Fish Feel Pain?: "it's a tricky issue, so I'll go with my gut"
   
3. In the Basement of the Ivory Tower: are some people just not meant for college?
4. Study Says Social Conservatives Are Dumb: but that doesn't mean they're wrong
5. You Don't Deserve Your Salary: no one does
   
   
6. The Financial Crisis Killed Libertarianism: if it wasn't dead to begin with
7. How'd Economists Get It So Wrong?: Krugman says the least wrong was Keynes
8. An Open Letter to Krugman: get to know your field
9. Consider the Lobster: David Foster Wallace ponders animal ethics
10. The Dark Art of Interrogation: Bowden says torture is necessary
11. The Idle Life is Worth Living: in praise of laziness
12. Should I Become a Professional Philosopher?: maybe not
    
13. Blackburn Defends Philosophy: it beats being employed

Paper Guideline

Due Date: the beginning of class on Friday, April 23rd, 2010

Worth: 5% of final grade

Length/Format: Papers must be typed, and must be between 300-600 words long. Provide a word count on the first page of the paper. (Most programs like Microsoft Word & WordPerfect have automatic word counts.)

Assignment:
1) Pick an article from a newspaper, magazine, or journal in which an author presents an argument for a particular position. There are some links to potential articles here. I recommend choosing from those articles, though you are also free to choose an article on any topic you want.

TIP: It’s easier to write this paper on an article with a BAD argument. Try finding a poorly-reasoned article!

You must show Sean your article by Monday, April 19th for approval. The main requirement is that the article present an argument. One place to look for such articles is the Opinion page of a newspaper. Here’s a short list of some other good sources:

• The New Yorker
• Slate
• New York Review of Books
• London Review of Books
• Times Literary Supplement
• Boston Review
• Atlantic Monthly
• The New Republic
• The Weekly Standard
• The Nation
• Reason
• Dissent
• First Things
• Mother Jones
• National Journal
• The New Criterion
• Wilson Quarterly
• The Philosophers' Magazine
  

(for even more sources, check out the left-hand column of Arts & Letters Daily)

2) In the essay, first briefly explain the article’s argument in your own words. What is the position that the author is arguing for? What are the reasons the author offers as evidence for her or his conclusion? What type of argument does the author provide? In other words, provide a brief summary of the argument.
NOTE: This part of your paper shouldn’t be very long. I recommend making this about one paragraph of your paper.

3) In the essay, then evaluate the article’s argument. Overall, is this a good or bad argument? Why or why not? Systematically evaluate the argument: Check each premise: is each premise true? Or is it false? Questionable? (Do research if you have to in order to determine whether the author’s claims are true.) Then check the structure of the argument. Do the premises provide enough rational support for the conclusion? Does the argument contain any fallacies? If you are criticizing the article’s argument, be sure to consider potential responses that the author might offer, and explain why these responses don’t work. If you are defending the article’s argument, be sure to consider and respond to objections..
NOTE: This should be the main part of your paper. Focus most of your paper on evaluating the argument.

4) Attach a copy of the article to your paper when you hand it in. (Save trees! Print it on few pages!)

Have You Stopped Loading Questions?

Begging the Dinosaur

I couldn't resist giving you some stuff on begging the question. Here's my favorite video for Mims's logically delicious song "This is Why I'm Hot":

Let's Be Diplomatic: Straw Person

Here's some stuff on the straw man fallacy:

• Politicians love to distort their opponents' positions. Even Obama does it.
• Politicians aren't alone: we do it, too. Often we distort arguments for claims we disagree with without even realizing it. This is because we have trouble coming up with good reasons supporting a conclusion that we think is false, so we have a tendency to make up bad reasons and attribute them to our opponents.
  
• Hire your own professional straw man!

Also, speaking of red herrings, here's a cute cat picture:

Wait, we weren't just speaking of red her--Oh. I see what you did there.

Clever.

By Request

It wasn't here when you wrote it, but it is now:

Class Canceled Monday 3/22

Monday's class (March 22nd) is canceled. Sorry for the late notice.

Accentuate the Fallacy

The dark cartoon strip Cyanide & Happiness often employs amphiboly and the fallacy of accent for humorous results.





This one has a double accent fallacy:

Group Presentations

UPDATE: Here are the new dates for each presentation. Two groups will be going on some days.

Here are the assigned groups for the group presentations on fallacies, along with your topics and the tentative date of each presentation (those dates will probably be pushed back):

1. Accent & Division (already went): Bryan H., Hunter
   
2. Ad Hominem & Appeal to Force (already went): Andrew, Courtney, Kelly
   
3. Appeal to Pity & Popular Appeal (Monday, 3/22): Bob, Nick
   
4. Appeal to Ignorance & Hasty Generalization (Monday, 3/22): Fred, Justin, Lillie
   
5. Straw Man & Red Herring (Wednesday, 3/24): Jason, Jay
   
6. Begging the Question & Loaded Question (Friday, 3/26): Brent, Miranda
   
7. Appeal to Authority & False Dilemma (Friday, 3/26): Chris, Kyle, Tracey
   
8. Slippery Slope & The Naturalistic Fallacy (Monday, 3/29): Brian L., Dane
   

Feedback Wanted

Now that we're halfway through the course, I want to know what you like and dislike about the class so far. Give us your anonymous feedback in the comments to this post. In particular, I'd like to hear any constructive criticism you have, and tips for making the class better.

That's an Ad Hominem, Jerk

Here's some links on the ad hominem (personal attack) fallacy:

• Sure, some critics of Obama are racist, but does that mean we can dismiss their arguments? As much as we might want to, logically, no we cannot!
• Some variants on the personal attack: tu quoque (hypocrite!) and guilt by association (she hangs around bad people!).
• I should note that tu quoque isn't always fallacious reasoning.
  
• "The ad hominem rejoinders—ready the ad hominem rejoinders!"
• Remember our rallying cry: "STUPID PEOPLE SOMETIMES SAY SMART THINGS."
  

Get to studying, you ignorant sluts.

Midterm

Just a reminder: The midterm will be held at the beginning of class on Friday, March 12th. It's worth 15% of your overall grade, and will cover everything we've done in class so far:

• definitions of 'logic,' 'reasoning,' and 'argument'
  
• evaluating arguments
• types of arguments:
  -deductive (aim for certainty, are valid/invalid and sound/unsound)
  -inductive (generalizing from examples, depend on large, representative samples)
  -args about cause/effect (correlation vs. causation)
  -abductive (inferences to the best explanation)
  
• the 4 to 6 fallacies covered in class so far
  

Get to studying!

Take My Wife, As Amphiboly

Here's some stand up from Henny Youngman, the violin-toting comedian who came up with "Take my wife... please!" How many jokes rely on amphiboly?

Fallacies, Fallacies, Everywhere

Looking for links on fallacies and equivocation? This is your post! First, there's a nice series of short articles on a bunch of different fallacies, including many that aren't in our book.... but also an entry on equivocation.

Speaking of, my best friend the inter-net has some nice examples of the fallacy of equivocation. Here is one good one:

A feather is light.

What is light cannot be dark.
Therefore, a feather cannot be dark.

Murder on the Abductive Express

Here's a paper that explains why I disagree with our textbook's explanation of the scientific method. It's important to consider and test multiple possible explanations rather than a single hypothesis:

• J.R. Platt's "Strong Inference" (pdf)

(NOTE: Platt uses the word "inductive" in a more general way than we do in class, to refer to any non-deductive kind of reasoning--that is, arguments that don't attempt to absolutely prove their conclusion.)

Also, in honor of abductive arguments, here's a dinosaur comic murder mystery.

P.S. I just bought this book: Inference to the Best Explanation by Peter Lipton.

Correlatious

Here's yet another stick-figure comic (for those keeping track, that's four blog posts in a row). This one's about correlation.

Correlation is a tricky concept. We tend to see the world in all-or-nothing terms, rather than in shades of probability.

Another Snow Day!

Class is canceled today, Friday, February 26th, because of the snow. In fact, all CCC classes are canceled today.

Our Inductive Minds

Here are some more thoughtful links on inductive reasoning.

• What are the benefits and dangers of generalizations?
• What makes stereotyping illogical?
• Beware: we often make snap judgments before thinking through things. Then when we do think through things, we just wind up rationalizing our snap judgments.

Learning from Experience

Here's some stuff on inductive arguments. First, a video of comedian Lewis Black describing his failure to learn from experience every year around Halloween:


Next, this stick figure comic offers a pretty bad argument. Why is it bad? (Let us know in the comments!)

There's another stick-figure comic about scientists' efforts to get as big a sample size as they can to improve their arguments.

Structure

One of the trickier concepts to understand in this course is the structure of an argument. This is a more detailed explanation of the term. If you've been struggling to understand this term, the following might help you.

An argument's structure is its underlying logic; the way the premises and conclusion logically relate to one another. The structure of an argument is entirely separate from the actual meaning of the premises. For instance, the following three arguments, even though they're talking about different things, have the exact same structure:

1) All tigers have stripes.
Tony is a tiger.
Tony has stripes.

2) All humans have wings.
Sean is a human.
Sean has wings.

3) All blurgles have glorps.
Xerxon is a blurgle.
Xerxon has glorps.

There are, of course, other, non-structural differences in these three arguments. For instance, the tiger argument is overall good, since it has a good structure AND true premises. The human/wings argument is overall bad, since it has a false premise. And the blurgles argument is just crazy, since it uses made up words. Still, all three arguments have the same underlying structure (a good structure):

All A's have B's.
x is an A.
x has B's.

Evaluating the structure of an argument is tricky. Here's the main idea regarding what counts as a good structure: the premises, if they were true, would provide good evidence for us to believe that the conclusion is true. So, if you believed the premises, you would be able to figure out from those premises alone that the conclusion is worth believing, too.

Note I did NOT say that the premises are actually true in a good-structured argument. Structure is only about truth-preservation, not about whether the premises are actually true or false. What's "truth preservation" mean? Well, truth-preserving arguments are those whose structures guarantee that if you stick in true premises, you get a true conclusion.

The premises you've actually stuck into this particular structure could be good (true) or bad (false). That's what makes evaluating an arg's structure so weird. To check the structure, you have to ignore what you actually know about the premises being true or false.

Good Structured Deductive Args (Valid)
If we assume that all the premises are true, then the conclusion must also be true for an argument to have a good structure. Notice we are only assuming truth, not guaranteeing it. Again, this makes sense, because we’re truth-preservers: if the premises are true, the conclusion that follows must be true.

EXAMPLES:
1) All humans are mammals.
All mammals have hair.
All humans have hair.

2) If it snows, then it’s below 32 degrees.
It is snowing right now.
It’s below 32 degrees right now.

3) All humans are mammals.
All mammals have wings.
All humans have wings.

4) Either Yao is tall or Spud is tall.
Yao is not tall.
Therefore, Spud is tall.

Even though arguments 3 and 4 are ultimately bad, they still have good structure (their underlying form is good). The second premise of argument 3 is false—not all mammals have wings—but it has the same exact structure of argument 1—a good structure. Same with argument 4: the second premise is false (Yao Ming is about 7 feet tall), but the structure is good (it’s either this or that; it’s not this; therefore, it’s that).

To evaluate the structure, then, assume that all the premises are true. Imagine a world in which all the premises are true. In that world, MUST the conclusion also be true? Or can you imagine a scenario in that world in which the premises are true, but the conclusion is still false? If you can imagine this situation, then the argument's structure is bad. If you cannot, then the argument is truth-preserving (inputting truths guarantees a true output), and thus the structure is good.

Bad Structured Deductive Args (Invalid)
In an argument with a bad structure, you can’t draw the conclusion from the premises – they don’t naturally follow. Bad structured arguments do not preserve truth.

EXAMPLES:
1) All humans are mammals.
All whales are mammals.
All humans are whales.

2) If it snows, then it’s below 32 degrees.
It doesn’t snow.
It’s not below 32 degrees.

3) All humans are mammals.
All students in our class are mammals.
All students in our class are humans.

4) Either Yao is tall or Spud is short.
Yao is tall.
Spud is short.

Even though arguments 3 and 4 have all true premises and a true conclusion, they are still have a bad structure, because their form is bad. Argument 3 has the same exact structure as argument 1—a bad structure (it doesn’t preserve truth).

Even though in the real world the premises and conclusion of argument 3 are true, we can imagine a world in which all the premises of argument 3 are true, yet the conclusion is false. For instance, imagine that our school starts letting whales take classes. The second premise would still be true, but the conclusion would then be false.

The same goes for argument 4: even though Spud is short (Spud Webb is around 5 feet tall), this argument doesn’t guarantee this. The structure is bad (it’s either this or that; it’s this; therefore, it’s that, too.). We can imagine a world in which Yao is tall, the first premise is true, and yet Spud is tall, too.

Evaluating Deductive Arguments

Here are the answers to the handout on evaluating deductive arguments that we went over in class. Perhaps I should have titled the handout "So Many Bad Args!"

1) All kangaroos are marsupials.
All marsupials are mammals.
All kangaroos are mammals.

P1- true
P2- true
structure- valid
overall - sound

2) (from Stephen Colbert)
Bush was either a great prez or the greatest prez.
Bush wasn’t the greatest prez.
Bush was a great prez.

P1- questionable ("great" is subjective)
P2- questionable ("great" is subjective)
structure- valid (it's either A or B; it's not A; so it's B)
overall- unsound (bad premises)

3) Some people are funny.
Sean is a person.
Sean is funny.

P1- true (we might disagree over who specifically is funny, but nearly all of us would agree that someone is funny)
P2- true (each "Sean" in this handout refers to your teacher, Sean Landis)
structure- invalid (the 1st premise only says some are funny; Sean could be one of the unfunny people)
overall- unsound (bad structure)

4) All email forwards are annoying.
Some email forwards are false.
Some annoying things are false.

P1- questionable ("annoying" is subjective)
P2- true
structure- valid (the premises establish that some email forwards are both annoying and false; so some annoying things [those forwards] are false)
overall - unsound (bad first premise)

5) All bats are mammals.
All bats have wings.
All mammals have wings.

P1- true
P2- true (if interpreted to mean "All bats are the sorts of creatures who have wings.") or false (if interpreted to mean "Each and every living bat has wings," since some bats are born without wings)
structure- invalid (we don't know anything about the relationship between mammals and winged creatures just from the fact that bats belong to each group)
overall- unsound (bad structure)

6) Some dads have beards.
All bearded people are mean.
Some dads are mean.

P1- true
P2- questionable ("mean" is subjective)
structure- valid (if all the people with beards were mean, then the dads with beards would be mean, so some dads would be mean)
overall- unsound (bad 2nd premise)

7) This class is boring.
All boring things are taught by Sean
This class is taught by Sean.

P1-questionable ("boring" is subjective)
P2- false (nearly everyone would agree that there are some boring things not associated with Sean)
structure- valid
overall- unsound (bad premises)

8) All students in here are mammals.
All humans are mammals.
All students in here are humans.

P1- true
P2- true
structure- invalid (the premises only tell us that students and humans both belong to the mammals group; we don't know enough about the relationship between students and humans from this; for instance, what if a dog were a student in our class?)
overall- unsound (bad structure)

9) All hornets are wasps.
All wasps are insects.
All insects are scary.
All hornets are scary.

P1- true!
P2- true
P3- questionable ("scary" is subjective)
structure- valid (same structure as in argument #1, just with an extra premise)
overall- unsound (bad 3rd premise)

10) All students in here are humans.
All humans are shorter than 10 feet tall.
All students in here are shorter than 10 feet tall.

P1- true
P2- true!
structure- valid (same structure as arg #1)
overall- sound

11) If Sean sings, then students cringe.
Sean is singing right now.
Students are cringing right now.

P1- questionable (since you haven't heard me sing, you don't know whether it's true or false)
P2- false
structure- valid
overall- unsound (bad premises)

12) If Sean sings, then students cringe.
Sean isn't singing right now.
Students aren't cringing right now.

P1- questionable (again, you don't know)
P2- true
structure- invalid (from premise 1, we only know what happens when Sean is singing, not when he isn't singing; students could cringe for a different reason)
overall- unsound (bad 1st premise and structure)

13) If Sean sings, then students cringe.
Students aren't cringing right now.
Sean isn't singing right now.

P1- questionable (again, you don't know)
P2- true
structure- valid
overall- unsound (bad 1st premise)

14) If Sean sings, then students cringe.
Students are cringing right now.
Sean is singing right now.

P1- questionable (again, you don't know)
P2- false
structure- valid (from premise 1, we only know that Sean singing is one way to guarantee that students cringe; just because they're cringing doesn't mean Sean's the one who caused it; again, students could cringe for a different reason)
overall- unsound (bad premises and structure)

Quiz You Once, Shame on Me

The first quiz will be held at the beginning of class on Wednesday, February 17th (we're pushing it back one more class because of the snow day). You will have about 25 minutes to take it.

There will be a multiple choice section, a section on evaluating deductive arguments, a section on evaluating arguments, and a section where you provide examples of specific kinds of arguments. Basically, it will look like a mix of the homework and group work we've done in class so far.

The quiz is on what we have discussed in class from chapters 6, 8, and part of 7 of the textbook. Specifically, here's what will be covered on the quiz:

• definitions of: logic, reasoning, argument, structure, sound, valid, deductive, inductive
• understanding arguments
• evaluating arguments
  
• deductive args (valid & sound)
• inductive args (if we get to them in class on Friday or Monday)
  

The quiz is worth 7.5% of your overall grade. Feel free to insult me in the comments for putting you through the terrible ordeal of taking a quiz.

Snow Day!

Our class is canceled Wednesday, February 10th, because of the snow. In fact, all day and evening classes at Camden County College are canceled until Thursday Friday.

(This means our homework is now due Friday.)

Enjoy!

Homework #1

As I mentioned in class, our first homework assignment is to evaluate the arguments from #1 (a) through (h) on pages 187-188 of the textbook. The homework is due at the beginning of class on Wednesday, February 10th, and is worth 40 points (4% of your overall grade).

On an unrelated note, I found the reason the internet exists: hipster puppies.

sounder isn’t exactly sure what dubstep is, but is still complaining about the lack of it at pitchfork fest this year

Defining Our Terms

1. Tool: I suggest watching Tool Academy to see our heroes in action:


2. Fugly: uh, rather ugly. Moe Szyslak has been called a few variations of this term.

3. Hipster: Urban Dictionary's entry is OK, but I like Wikipedia's entry on this term. If you want to find/become a hipster, try this helpful handbook, or this picture of the evolution of the hipster.