Informal Logic: Deduction and Arguments

This is the second part of Professor White's discussion of informal logic. The first part is Informal Logic: Deductive Reasoning.

Deduction and arguments

We have seen that we can deduce new conditionals from old. But where do we get conditionals to start with? Fortunately, we can get conditionals from our three principles. Premise (5) in Part 1's LSAT example was shorthand for a collection of conditionals; in the same way, both non-contradiction and excluded middle provide us with several conditionals. For example, excluded middle gives us "if P is not true, then P is false" for anything we want to fill in the blank for P.

In addition to conditionals, these principles get us two more induction techniques beyond simple if-then arguments. In reality, these arguments could be converted to if-then deductions if we wanted to. These additional methods are just templates that help us speed up the process a bit.

Argument by contradiction

In an argument by contradiction, we provisionally assume that a claim is false. We then deduce a premise is false. As a valid argument is an argument about true premises, this violates the principle of non-contradiction. Hence our deduction had to have made a mistake somewhere. The only possible mistake was our initial assumption that the claim is false, so it cannot be false. By the principle of excluded middle, this means this claim is true.

Returning to our LSAT example from Part 1, suppose we want to deduce the claim

One of P, G, or S cannot be cut.

To argue by contradiction, we start assuming that this claim is false. In other words, all three of them are cut. When G and S are cut, we can deduce from premise (2) that W is cut. By premise (5) we know that two of L, M, and R must be cut. Counting all these up, we get at least six areas that must be cut. This contradicts premise (1), so one of the initial three—P, G, or S—cannot be cut.

Argument by cases

In an argument by cases, we start with a claim and create two arguments: one assuming the claim false, and another assuming the claim true. If we can deduce the same conclusion in both cases, then that conclusion is valid because of the principle of excluded middle.

Returning to our LSAT example, suppose we want to deduce the claim

If R is not cut, then G must be cut.

We are deducing a conditional, so we start with the provisional assumption that R is not cut. We can immediately deduce, from premise (4), that L and M are cut. By premise (1), we need to reduce three more areas from G, S, W, and N. We now break our argument into two cases:

• N is not cut. This leaves us only three areas left to choose from, so G must be cut.
• N is cut. We deduce from premise (3) that S is not cut. That leaves us only two areas to choose our remaining two cuts from, so G must be cut.

G is cut in both cases, so we have successfully argued "if R is not cut, then G must be cut."

In practice, these arguments rarely have a true/false breakdown. Instead, they start with an exhaustive list of possibilities and use them as the cases. For example, if we want to argue that tuition at Ivy League schools is too expensive, we can list all of the Ivy League schools and present a separate argument for each. Be warned that this approach has an unstated premise, namely that the list covers all of the possibilities. Ignoring this additional premise is the source of the false dilemma fallacy.

***

Please thank Professor White in the comments for sharing these articles!

Photo by wallyg

Logic and Games, Lawsuit Edition

* What to do when the house you just bought turns out to be haunted? Sue, of course. [Google Scholar]

* What to do when a $40,000 donation doesn't get your kid into college? Sue, of course. [Slate]

* The Simpsons imagines a world without lawyers where the above lawsuits never happen. [YouTube]

* Supreme Court Justice Antonin Scalia says women don't have constitutional protection against discrimination. In other news, he hasn't gotten laid since making that statement. [Huffington Post]

* Police can't go through your cell phone after they pull you over, or can they? High school kids had better cut back on the sexting. [Ars Technica]

* Republican state lawmakers have their own take on the 14th amendment. [Above The Law]

* Want to skip 3 years of law school? Buy your law degree on eBay for $200,000. [ABA Journal]

LSAT Diary: Score Release Wait

UPDATE: Lisa got a 175!

Here's what she wrote:

"I got my LSAT score yesterday and was thrilled to find out that I got a 175. I really want to thank you for all the information you put on your blog and for offering the 3-month-study schedule that I followed...There's not enough I can say to thank you."

If you want to be in LSAT Diaries, please email me at LSATUnplugged@gmail.com. (You can be in LSAT Diaries whether you've taken the exam already or not.)

Please thank Lisa for her advice below in the comments!

(And see her previous LSAT Diary here.)

Lisa's LSAT Diary:

The window by my desk looks across the snow-covered roofs of dozens of houses in my sister’s subdivision in south-central Wisconsin. When I first began studying for the LSAT, the roofs were not covered with snow; rather the trees were covered with leaves: green leaves, then shades of orange and red. Now the leaves are gone, and my comfortable schedule of getting up, studying for the LSAT, making dinner for my husband and sister, watching The Office, and going to bed, has ended. The December LSAT has come and gone, and I’m left reluctantly facing the real world again.

Last year, my husband and I celebrated Christmas in Taiwan (where houses are condos, crowded together in multi-story buildings, and not a flake of snow is to be found). The season was marked with excitement: Despite having no idea whether any of our plans would turn out, we had decided to go ahead and leave our jobs in the spring, travel around Europe for three months, and move 13 time zones away to Wisconsin, where I grew up. We turned our backs on the security of jobs or even a good back-up plan because we both knew that the time had come to move on.

Eight months later, some of our plans had fallen through but new and unexpected ones had emerged. Like my plan to go to law school, and our plan to live with my sister and brother-in-law until we found jobs. I soon discovered that studying for the LSAT was much more rewarding than looking for a job. After all, when I finished a PrepTest, I was only a minute away from a score. I never heard back from most companies I sent resumes to. Yet a strange dichotomy emerged: Somehow I could regularly snag scores of 172 and up on PrepTests and yet couldn’t seem to figure out how to get someone to notice my resume. As strange as this may sound, the LSAT had become a method of procrastination.

And procrastinate I did. I followed the 3-month LSAT study schedule. I took 20+ PrepTests. Slowly, PrepTest after PrepTest I began to see patterns in logical reasoning questions, the section I most needed to improve. The correct answer for necessary assumption questions, a weakness, started to take on a certain “feel.” I came to relish sufficient assumption questions for the relative simplicity of “connecting the dots” to make the conclusion work.

I improved my speed and accuracy on long parallel reasoning or parallel flaw questions by carefully diagramming the stimulus and then mimicking that diagram with dots and arrows beside each answer to see if the argument followed the same flow. I wrote out why the correct answer was right for every logical reasoning question I got wrong.

When the actual LSAT came in December I was confident and ready. The LSAT had truly “become my friend.” The LSAT had restored my confidence in my academic abilities. Six years of work had made me wonder if I had the mental stamina to “hit the books” again.

When I started studying, I realized two things: The college student in me was long gone, and that was a good thing. As a college student, studying was simply something I did. As an unemployed professional, studying was an investment that could possibly see a return as scholarship funds. As a college student, the world and all its choices lay ahead of me. As a married woman pushing 30, I was becoming more deliberate about my choices because I realized they come with an opportunity cost.

Now I am left waiting for my score, finishing up my applications and finally facing the job market. Just this past week I lost an opportunity to work at a law firm as a paralegal because I honestly answered pointed questions about my future plans. Realizing that my honesty would probably close the door on any full-time, permanent positions, I am now looking for temporary jobs. Fortunately, the people in staffing agencies seem to think there is a place for out-of-work editors and I already have a promising job lead. In the meantime, if you need something proofed, let me know.


Update:

I got my LSAT score yesterday and was thrilled to find out that I got a 175. I really want to thank you for all the information you put on your blog and for offering the 3-month-study schedule that I followed. I was unsure at first about using so many preptests as a part of prep, but quite a lot of advice I found seemed to support that, and now I am very glad that I decided to go that way and study on my own. After a while, it seemed that I had reached some sort of "plateau," but I really do think that consistently working on my weaknesses and studying each test (each question) thoroughly helped me to improve so that the last 5 or 6 tests before the LSAT my average was at 175-176. How I was able to actually score my average despite test nerves, I don't know, though I do have to thank LSAC for giving the December LSAT such a generous curve.

There's not enough I can say to thank you. I absolutely recommend self-study for anyone who has the initiative and discipline to keep at it. I think I was able to do better through self-study rather than a program because I had to depend on myself and not a teacher for my test prep.


Photo by carbonnyc

Free LSAT Logic Games Explanations | Advanced Linear

My free Advanced Linear Logic Game about monkeys in space has been without a complete setup explanation for far too long. Several of you have rightfully hounded me about this shameful omission, so here you go:

The description of the main diagram states:

The seats are in consecutive rows that are numbered 1, 2, 3, and 4 from front to back. Each row contains exactly two seats: a seat with a window facing the sun and a seat with a window facing the moon.

Normally, I'd put the numbers 1, 2, 3, and 4 as the "base" (running horizontally). However, because the term "rows" typically describes sets of variables that are horizontal (as anyone who regularly uses Microsoft Excel can tell you), I'm going to make the numbers run vertically on the diagram.

The description gives us the following:











If you want to do make your numbers run horizontally that's perfectly fine. You'll just have to rotate everything 90 degrees as punishment for diagramming contrary to the way I do things.

Additionally, the placement of S on the left and M on the right is arbitrary.

Now, the rules, starting with the 1st rule:

E's window never faces the sun, but D's window always faces the sun.

Since E doesn't face the sun, it must face the moon. Put E below the moon column. Put D below the sun column.

The 2nd rule:

F sits in row 1 or row 2, but neither row 2 nor row 3 can contain D.

Place F with a slash through it next to rows 3 and 4, and D with a slash through it next to rows 2 and 3.

What you have should look something like this:













The next rule is a bit tricky to diagram:

B sits in the row immediately behind D's row.

Thing is, they may not be in the same column (facing the same thing). 2 quick inferences we can make are that D's not in row 4, and B's not in row 1 (otherwise, how could B go behind D?). Since we already know D isn't in rows 2 or 3, it must be in 1. Since B's in the row immediately behind D's, it must be in row 2.

Here's one way you might want to diagram the rule itself (along with the new inferences included on the diagram):












Of course we no longer need the indications of the rows that D and B aren't going in, since we know exactly which rows they are going in. We now know that D must go in S1. I'll erase the redundant information in the next pictured version of the diagram.

For now, the next rule:

If B's window faces the sun, then A's window faces the moon.

We can simply say, Bs -> Am.

The contrapositive would be:

If A's window does not face the moon, then B's window does not face the sun.

However, if A's window is not facing the moon, we know it must be facing the sun. Similarly, if B's window is not facing the sun, it must be facing the moon.

As such, rather than writing the contrapositive in negative terms, we can write it in positive ones:

If A's window faces the sun, then B's window faces the moon.

Diagrammed, this gives us: As -> Bm

We can simply write both of these conditional statements to the side of the diagram.

The next rule:

If D sits in row 1, then G sits in row 4.

Although this is a conditional statement, we already know through our inferences that D must, in fact, be in row 1. As such, since the sufficient condition of this rule must always be met, the necessary condition must always be met as well. We know with certainty that G must be on 4. Therefore, we should place G next to row 4.

We now have the following:













However, we can actually make two main diagrams, based upon whether B's window faces the sun or moon:













Now, when B faces the sun, we know A faces the moon, so we can go ahead and place A under the moon column in that particular diagram.

Now, the final rule:

If B sits in the same row as F, then G's window faces the sun.

We already knew F couldn't be in either of rows 3 or 4. Now, we also know that when it's in row 2 (since B's always in 2), we'll get even more information.

We can diagram this rule as the following:

Every valid scenario must fall within 1 of these above 2 diagrams, and they're more than enough to move on to the questions. By creating these up-front, you give yourself more of a starting point to draw hypothetical scenarios over the course of the game for particular questions. The game is too open-ended for you to draw every scenario up-front, but these diagrams will allow you to solve the questions more easily.

Most of you should simply move on to the questions with the diagrams that I've laid-out above. What we've done so far is enough to solve the questions without trouble.

However, if you'd like to see how it is possible to break the main diagrams apart even further (simply as an exercise), I'll show those of you are interested how to do so, below.


***

You can split each of the 2 main diagrams above into 2 more (resulting in 4 main diagrams for all the non-math whizzes out there), based upon whether F goes to row 1 or row 2 in each of those diagrams.

On the left side, where B's window faces the sun, I have F in row 1 in the top diagram and in row 2 in the bottom diagram.

On the right side, where B's window faces the moon, I have F in row 1 in the top diagram and in row 2 in the bottom diagram.

Here's what it looks like:


















Now, in the bottom 2 diagrams, B and F are in the same row. As such, G's window must face the sun in those diagrams. In the others, we simply don't know whether G's window faces the sun or the moon.

One more inference to make: the seat in the 3rd row facing the sun is particularly limited in the two diagrams on the left.

Since A's window must face the moon in these diagrams, A can't go there in these diagrams. Additionally, none of B, D, E, F, and G can go there - B, D, F have already been placed, G must go in row 4, and E's window must always face the moon. As such, only either C or H can go in that seat on those diagrams. I'll place C/H in the 3rd seat facing the sun on both of these diagrams:
























Every valid scenario must fall within 1 of these 4 diagrams. By creating these up-front, you give yourself more of a starting point to draw hypothetical scenarios over the course of the game for particular questions.

Photo by donsolo

Logic and Games: Happy New Year!

* Caveon Test Security will hunt you down if you try to cheat on the LSAT. [NYTimes]

* Hitler gets mad about how one law school applicant's admissions cycle is going. [YouTube]

* "I feel that you should be aware that some asshole is signing your name to stupid letters." [Above The Law]

* Bet you didn't know that some lawyers are sketchy. [LA Times via ABA Journal]

* Christine "I'm Not A Witch" O'Donnell claims thug (warlock?) tactics behind accusations of campaign $ misuse. [Huffington Post]

* The first year of law school - in 5 minutes. [FindLaw]

* A couple travels across the Congo in a Land Cruiser. And it's more fun than LSAT prep. [Expedition Portal]

LSAT Test Dates for the 2011-2012 Admissions Cycle

The LSAT test dates for the 2011-2012 admission cycle (PDF) (June 2011 - February 2012) have finally been released by LSAC.

For this past cycle, the LSAT test dates for October 2010, December 2010, and February 2011 LSATs were a week later than usual. (You can see previous LSAT test dates below.)

However, for the upcoming cycle, things appear to be largely back to normal.

The September/October 2011 LSAT is back to being the first Saturday in October (the Sep/Oct LSAT is typically the 1st Saturday in October or the last Saturday in September).

The December 2011 LSAT is back to being the first Saturday in December, as the December LSAT typically has been.

However, the February 2012 LSAT is a week later than usual again.

A few possible explanations:

1. LSAC is simply trying to spread out the LSAT test dates more (since the largest gap between LSATs is the one between February and June).

2. LSAC wants the February 2012 LSAT to be closer to 12-21-2012, the end of the Mayan calendar (and the world). This way, Feburary 2012 LSAT-takers will spend more of their precious days on Earth studying without ever going to law school. Mean, huh?

3. LSAC just likes punishing most February LSAT-takers by making them apply even later in the cycle than they already are.

At the very bottom of this blog post, I've included some thoughts from my previous LSAT test dates blog post about why the February test being later than typical is bad news.

Evidence - LSAT Test Administration Dates Over Time:

June Test Dates
Monday, June 6, 2005
Monday, June 12, 2006
Monday, June 11, 2007
Monday, June 16, 2008
Monday, June 8, 2009
Monday, June 7, 2010
Monday, June 6, 2011


September / October Test Dates
Saturday, October 2, 2004
Saturday, October 1, 2005
Saturday, September 30, 2006
Saturday, September 29, 2007
Saturday, October 4, 2008
Saturday, September 26, 2009
Saturday, October 9, 2010
Saturday, October 1, 2011



December Test Dates
Saturday, December 4, 2004
Saturday, December 3, 2005
Saturday, December 2, 2006
Saturday, December 1, 2007
Saturday, December 6, 2008
Saturday, December 5, 2009
Saturday, December 11, 2010
Saturday, December 3, 2011


February Test Dates
Saturday, February 12, 2005
Saturday, February 4, 2006
Saturday, February 10, 2007
Saturday, February 2, 2008
Saturday, February 7, 2009
Saturday, February 6, 2010
Saturday, February 12, 2011
Saturday, February 11, 2012


For February Test-Takers
Taking the LSAT this late in the cycle was less than ideal already, so you really didn't need it to be a week later. When the LSAT test date moving a week later, the score release date also moves a week later. The February 2011 LSAT's scheduled score release date is March 7th, 2011, and the February 2012 LSAT's scheduled score release date is March 7, 2012. Even though LSAC generally releases scores a few days early, they don't release February LSAT scores a full week early.

The especially-bad news - some law schools have March 1st application deadlines.

This means a February 2011 LSAT / February 2012 LSAT score won't do you any good for that cycle if your desired law school has a March 1st deadline. You need to look into your particular law school's application deadlines to determine this sooner rather than later.

If you're set on applying in the upcoming cycle (and especially if your school has a March 1st deadline), I'd recommend taking the LSAT in June or October to give yourself another test (October or December, respectively) to fall back on.

Photo by gc_photography

LSAT Diary: General Prep Advice

UPDATE: Lisa got a 175!

Here's what she wrote:

"I got my LSAT score yesterday and was thrilled to find out that I got a 175. I really want to thank you for all the information you put on your blog and for offering the 3-month-study schedule that I followed...There's not enough I can say to thank you."

If you want to be in LSAT Diaries, please email me at LSATUnplugged@gmail.com. (You can be in LSAT Diaries whether you've taken the exam already or not.)

Please thank Lisa for her advice below in the comments!

Lisa's LSAT Diary:

Because it’s been more than a few years since I attended school for anything other than learning a new language or how to develop film, I knew I needed a solid game plan as I approached the LSAT. After searching for LSAT study plans, I found LSAT Blog with Steve at the helm giving practical and useful advice to all comers.

I soon found myself loaded with nearly every LSAT PrepTest. The 3-month LSAT schedule provided by Steve went up on the wall in my breakfast nook along side the growing list of “Don’t Forget These Words”, and stacks of reading material took up residence on the nearby buffet. Like most folks, I have a busy schedule. I have a consulting business and volunteer on a city commission, an agency task force and serve as the boardmember for a local non-profit dedicated to improving the education of our children.

It’s possible I went a little overboard when I got rid of the television (ok, it was only partially functional to begin with) and realigned my schedule to give myself Sunday afternoon off. Each day, I would get up early enough to give myself 4 hours before work to study. As soon as I started taking full PrepTests, my evenings would mean sitting with the answer sheet and a stack of paper to work through missed questions rather than heading out with friends.

Early in the process, I spent a couple of weeks visiting family - with a hundred pages of prep tests to keep me company. No trashy novels for this visit to the lake. Luckily for me, my family is full of late sleepers and didn’t realize I was sitting outside as the sun rose, pencil continuously working.

My first PrepTest, before opening a book or having any idea what I was getting into, was a 150. Leaving me plenty of room for improvement.

I worked my way through the PrepTests and with each timed full test was pleased to see my scores rising until I pulled a 172. While I don’t know my actual score yet, here's the advice I would offer:

1. Focus - clear the decks of all other obligations and make your preparation the main thing in your life. There’s plenty of time to party/sleep/read after the exam and you’ll just kick yourself if you slack off and don’t do as well as you would like.

2. Review - when you have an incorrect answer, just mark the question wrong as you’re scoring. Then, go back to all those you got wrong and rework each one until it makes sense. Use the one of the many resources available online to see the analysis performed on those you got wrong.

3. Visualize - check out the site where you are taking the test. If you know the specific room great, if not, check out likely rooms and call the site administrator to ask if they know the specific room. Visualize your day of routine, arriving at the site, settling in, opening the test and working easily through the exam.

4. Play - organize individual games into like sets, that is, put all the Grouping or Linear together and motor through them as a set. Repetition works.

5. Read - don’t let the reading comprehension section scare you. The stories change but the setup and questions repeat. Learn to love the word “historiography” even if you can’t pronounce it without embarrassing yourself. Enjoy the RC sections, they are fascinating if you can set aside the reason you find yourself glued to them.

6. Fun - whatever mantra you need to remind yourself that what you are learning is fun and interesting - do it and remind yourself when you get out of bed, while brushing your teeth and just before falling asleep.

On Test Day, I found myself standing in line with all the other ziploc baggie holding folks and I was reminded of other big tests. The difference was, I wasn’t nervous. I’d practiced and was comfortable with my timing and scores. I’m generally not into visualization, it feels a little too woo-woo for my tastes but I had done it on the theory that it couldn’t hurt and it might help. As I sat in the test room waiting for every last seat to be filled I was relaxed and comfortable, watching as others were nervously chattering away, fidgeting or tapping their feet.

After the exam was the big shock for me. When I stepped out into the sunshine planning for that evening’s festivities, I was faced with the parents of nearly every test-taker inside. I’m pretty sure they were as shocked to see me holding the same ziploc they’d packed for their kid as I was to see them. After all, I am older than most of the parents.

Photo by photosan0

How To Boost Your College GPA For Law School Admissions

While the LSAT's numero uno in law school admissions, GPA's also important.

Many of you are still in college and have time to do something to boost your GPA.

(To those of you with low GPAs are already fixed in stone, I'm sorry. You'll just have to make up for low GPAs with a rockin' LSAT score.)

My friend Cal Newport over at Study Hacks has made excerpts of his best-selling college advice books available for free on his website.

If you're still in college, his books are worth checking out. Not the common-sense advice you're used to seeing on the shelves. Check out the dozens of positive reviews on Amazon and see for yourself.

Excerpt from How to Become a Straight-A Student: The Unconventional Strategies Real College Students Use to Score High While Studying Less

Excerpt from How to Win at College: Surprising Secrets for Success from the Country's Top Students

I'm kind of shocked that these are only around $10 each - they're worth far more. I wish I'd had them when I was in undergrad.

Photo by ryanicus

LSAT Blog on Twitter: Like Celebrities?

LSAT Blog is on Friendster Facebook and Myspace Twitter, in case you hadn't noticed.

Sometimes, when you're on a Twitter user's profile, Twitter will recommend similar users to check out.

However, its recommendations aren't always the most accurate. For example, I'm apparently similar to Khloe Kardashian:

I have been trying to emulate her on LSAT Blog as much as possible - I just didn't think Twitter had noticed...

Below are a few other Twitter users I'm apparently similar to, but I just don't see the resemblance. Any ideas?

LSAT Blog's similar to Perez Hilton:












LSAT Blog's similar to Lil Wayne:












LSAT Blog's similar to Soulja Boy:













LSAT Blog's similar to Nicki Minaj:













LSAT Blog's similar to Diddy:













LSAT Blog's similar to 50 Cent:












I just don't get it...where are all the invitations to red carpet events? Do I have to drop an album first or something?

Logic and Games: Christmas Edition (Mostly)

* The stuff you learn in law school applies to supervillains & superheroes. Excited yet? [Law and the Multiverse via Above The Law]

* Santa puts Kaplan on naughty list after it's sued for racial discrimination & accused of sketchy online course signups. [NYTimes; HuffPost]

* Even The Grinch's heart would probably melt if he saw this. [YouTube]

* "You aren't supposed to hit things with sticks. Especially not Jesus." [Hyperbole and a Half]

* I see a Christmas miracle in which these 2 aren't punished for checking the African-American box on their law school applications. [Black People Love Us]

* Did you know a panda bear is saved every time a socialite eats a delicious cupcake? [NYTimes]

* Mom needs to chill with the whole tacos thing. [When Parents Text]

December 2010 LSAT: LSAT Blog Update

Many of you took the December 2010 LSAT. Hope it went well!

Blog reader Schopenhauer created comic-strip-style illustrations of his Test Day experience.

They're so good that I just have to include them in this post and share them with everyone (click to enlarge):

Pete became a logic superhero:

Nobody is feeling footloose and fancy free after an hours long standardized test, and Saturday, I was no exception. Subsequently, when I noticed a casual Facebook post on a friend's wall condemning an old scandal my favorite college football team was involved in, I felt compelled to write her a 500 word email picking her argument apart. If I hadn't taken the LSAT that very weekend, I may have just quirked an eyebrow at her post and moved on, but stress is a powerful force.

Nickie was upset that the proctors didn't enforce all the rules:

This guy brought in his cell which isn't allowed, a mechanical pencil even though we could only use regular pencils and a Starbucks cup that doesn't fit in a zipbloc. The proctors let him keep the phone in the room and he had to borrow pencils...I just wanted to turn to them and say, if you can't read the instructions on your admissions ticket, how the hell are you going to make it in law school.

Brenna has had a lot of fun before the test, even though (or because) she didn't really study:

Instead of studying for my LSAT, for the past 4 months I've been traveling around Europe and exploring my new home of Madrid. Whoops...it's wicked sweet to have absolutely no idea where I'll be living 7 months from now and what I'll be doing at that point in my life.

annajanine was tired:

All I know is that I was so mentally exhausted after it was done that I could barely remember my own name...

LSATtko is still studying for the LSAT, but this was too funny not to share:

I truthfully feel that the LSAT has a heart and if you start digging into it… I think you can feel the passion of the LSAT writers. They really love what they do...I’m actually finding each and everyone of those suckers so fascinating!...I can see the people visualizing me in some super hot steamy desert clutching madly at my LSAT prep tests and my tongue hanging to my knees. Believe me, that’s not where I’m coming from.

***

How'd the big day go for you?

Also see "How to Wait a Long Time for Your LSAT Score".


Photo by 10350347@N06

Logical Fallacies and Don't Ask, Don't Tell

On Wednesday, the House of Representatives passed a bill repealing Don't Ask, Don't Tell (DADT), the ban on allowing gays and lesbians in the military to serve openly.

The debate around DADT has been going on since it was first put into place as a legislative compromise in 1993.

However, passing an identical bill in the Senate is now the last major obstacle.

While I'd love it if everyone agreed with me and encouraged their senators to repeal the ban before the session ends, I'm more interested in seeing you engage in analysis of the arguments on both sides.

As such, here's what I'm going to do:

I'll dissect a couple of flawed arguments against repealing Don't Ask Don't Tell made by Senator John McCain, one of its most prominent advocates.

Then, I'd like to see you all, in the comments, point out flaws in the arguments of those favoring the repeal. Of course, you can also point out flaws in the arguments of those against repeal.

Why might you want to put yourself in the other side's shoes? Playing devil's advocate can help you to find weaknesses in your argument, leading you to ultimately improve its strength.

Anyway, here are a couple of flaws:

Moving the Goalposts

* In October 2006, Senator McCain said, "The day that the leadership of the military comes to me and says, 'Senator, we ought to change the policy,' then I think we ought to consider seriously changing it." (Wikipedia).

* In January 2010, when Defense Secretary Robert Gates and Chairman of the Joint Chiefs Mike Mullen came out in favor of changing the policy (repealing DADT), McCain suggested that they weren't really relevant because in their current posts, they don't directly lead troops (NYTimes).

In other words, McCain shifted the type of leadership position that he considered relevant. When a sufficient condition for him to consider changing the policy was met, he imposed new requirements (such as "further study").


Failure to Acknowledge Opposing Evidence

McCain said the support of Secretary Gates, Admiral Mullen, and other leaders wasn't enough - a study of DADT repeal's impact was necessary. A 10-month study Pentagon study basically found that DADT repeal wouldn't be so bad. However, it seems that because McCain didn't like the study's results, he refused to accept its validity. While we know from the LSAT that studies and surveys are often flawed or poorly-conducted, McCain's particular criticisms don't seem to carry much weight (Huffington Post / Daily Show).

Examples of the same flaw in actual LSAT questions:
PrepTest 30 (December 1999 LSAT), S2, Q2 (p54)
PrepTest 34 (June 2001 LSAT), S2, Q24 (p201)

***

There's a lot more I could say, but I'd really like to turn this discussion over to you.

What are some other flaws being committed on either side of the debate?

How about:

-Appeal to Emotion?
-Appeal to Popular Opinion?
-Straw Man (Misrepresenting the Argument)?

If so, what kinds of arguments contain them?

I look forward to reading your responses!

***

Further Reading:

Scott Brown And Lisa Murkowski Back Standalone DADT Repeal Bill [TPM]

House Votes to Repeal ‘Don’t Ask, Don’t Tell’ [NYTimes]

Rep. Louie Gohmert: Don't Ask, Don't Tell Repeal Threatens American 'Existence' (Video) [HuffPost]

Repeal Of DADT Paves Way For Gay Sex Right On Battlefield, Opponents Fantasize [The Onion]