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How recognizing a fallacy helps sniff out a poor argument

10 May

All cows have four legs

My dog Fido has four legs

Therefore, Fido is a cow

Pastor John Piper explained in a rebroadcasted sermon how high school geometry had grounded him in clear thinking.  Mathematical laws, one leading to a next, trained him to use deductive reasoning.  With practice in drawing valid and true conclusions, he developed a ‘nose’ for truth, as he put it.  The practical effect for him has been to alert him to ‘fishy’ conclusions that stink, that is they don’t add up, given the premises provided.

Looking at the syllogism above, we notice something and we ‘smell’ something:

  1. Premises 1 & 2 are in fact TRUE – cows have 4 legs and dogs normally do as well
  2. But we know that the conclusion is FALSE.  Our dog Fido is NOT a cow.

For me, the quickest way to explain why our sense of ‘fishiness’ is spot on, is to draw out each premise.

Take All cows have 4 legs.

Step 1:  draw a circle – label it Creatures with 4 legs.

2 cirlces

Step 2: draw a smaller circle somewhere inside the first circle.  This represents ALL COWS.  Every cow that ever WAS, IS, WILL BE  is in that circle.  (assuming no handicapped cows)

Step 3:  Mark an X in the big circle called, Creatures with 4 legs.

Circles with X

Do you spot the problem?  We don’t know where to place Fido.  Does he belong in the circle of cows? or out of the circle of cows?  From the information given, the 2 premises, that cannot be determined.

Therefore, the conclusion is false.  Why?  Because the new premise that ‘Fido is a cow’ assumes too much.  It might be, but it might not be.

There is of course, a technical way of categorizing the validity of the syllogism.  But for me, just sketching it out is simplest.

When I taught in a classical Christian school in Yorktown, Va, logic was a mandatory class for 7th and 8th graders.  I instructed the younger students in the joy of spotting fallacies (much to the annoyance of their parents who thereafter had to be on their guard!).  The 8th graders were at the perfect age to begin to understand how to analyze and formulate good arguments.

I believe that this tool in clear thinking is invaluable to young teens AND adults.  This kind of knowledge is powerful and builds confidence when they head out into a world such as ours:

Woe to those who call evil good, and good evil: who substitute darkness for light and light for darkness; who substitute bitter for sweet and sweet for bitter!  Woe to those who are wise in their own eyes and clever in their own sight!  Isaiah 5: 20-21 (NASB)

 

 

 

 

Logical Gal – Beware of a Distinction without a Difference

10 Dec

An old adage says it best: “He who distinguishes well, thinks well.”

Penseur

I love distinctions, but recently a conversation among Christians reminded me that one must take care NOT to invent a distinction where none exists.

The fallacy called Distinction without a Difference is so named because it is easy for us to be duped into thinking two ideas are different when all that varies are the words used to describe the two concepts.

Kids grow almost expert at using this fallacy on their parents.  Consider the following hypothetical conversation:

Mom  – Stop fidgeting, Johnny!

Johnny – I’m not fidgeting, I’m just moving my feet!

or how about this between two high school students:

Gal – I don’t want us to date anymore, Doug.

Guy – You mean it’s over, you and me?

Gal – No, it’s just that I don’t want to go out with you anymore.

breakup of a couple

The conversation snippet I heard the other day involved one pastor claiming that some Christians worship the Bible.

The other pastor, pushing back, maintained that Christians don’t worship a book, but take seriously the very words as they are written and the different contexts. They worship God as He reveals Himself in the Bible.

 

Bible

If someone asks – Do you love the Bible or do you love God?, how would you answer?

I would say, I love the Bible because it’s the supernatural (divine) intentional, powerful, breathed out record of God and His plan for His creation.  The Bible reveals the nature of God, which creates in me a growing knowledge and love for Him.  They are so connected, that I don’t separate them.  That’s like asking me which do I love more, my husband’s heart or his thoughts?  They are one and the same!

 

 

 

Logical Gal asks You, the readers, what You want

19 Jun

June 2013

About a year ago I started to blog around questions that could use some CLEAR THINKING.  These topics ranged from controversies in every day contemporary American life to deeper more lasting philosophical and religious issues.   My theme was ‘Surprised by Logic’ – a take off of CS Lewis’ book  Surprised by Joy.

I had been truly amazed at how helpful a tool both informal and formal logic turned out to be.  Hired to impart the basics of civics, US history, government and logic, I had to teach myself the latter my first year in a classical Christian school.  At first it seemed ‘impossible’, but gradually my mind was reshaped and conditioned to…surprise!….think more logically. I discovered first hand how useful mastering a few principles of logic could be to understanding an issue before forming my own view.

After 6 years both teaching and learning in that exceptional hub of education Here’s the link to the school, we moved to Western North Carolina where I am back to imparting ‘just’ French to students.  Not content to drop logic and its practical and empowering application to life, I started to blog.

Now as I approach the 1 year anniversary, I want to canvass you, the reader.  Can you help me and the direction of this blog by answering some of the questions below via the comment section?

Readers' Response

 

  1. What has been the most useful aspect of logic that you have picked up here or had reenforced by this blog?
  2. What questions or kinds of problems in your every day life do you see logic possibly helping?
  3. With whom do you share any of what you read here?
  4. What would you like to see addressed in future posts?
  5. What else should I know?
  6. Who are you? (categories….)

-an adult who once studied logic?

-an adult who never had logic?

-a teen?

-a teacher/guide of any sort responsible for the influence of others’ minds?

 

I thank you in advance for taking the time to add a comment, kind reader!

reader - child with glasses

 

 

Logical Gal – what makes something true?

17 Mar

Habit with him was all the test of truth, / It must be right: I’ve done it from my youth. -George Crabbe, poet and naturalist (1754-1832)

George Crabbe - Poet

Talk about redefining truth!  You’d think that a rule of life that stupid would be immediately laughed at and knocked down!

But before we ‘go all smug’ on poor Mr. Crabbe’s description of someone’s idea of truth, let’s stop a moment and reflect if we ourselves don’t rely on this fallacy in some version or another.

This Appeal to Tradition (or in Latin – argumentum ad antiquitatemcan take the shape of many habits that are harmful.  Just because something is habitual doesn’t make it healthy or right or lawful.

  • I always interrupt my husband; he doesn’t mind.
  • We always host our in-laws for Christmas; I’d feel guilty if we suggested otherwise.
  • The XYZ minority group are used to our comments.  What’s the big deal?

One of the dangers of relying on and NOT questioning tradition or habit is that you stop thinking through your reasons for doing something.

Tradition Fallacy

Tradition and habit are not bad in and of themselves.  In fact, solidifying some habits can be very beneficial! (i.e. questioning authority, thinking for yourself, verifying sources).  And there is a danger in rejecting an argument out of hand just because it is old.  (that’s another fallacy – Chronological Snobbery)

So how do we know when to hold on to tradition and when to jettison it? I don’t think that is the correct question.  For one thing, someone might continue to observe a tradition because it recalls an event precious to the community linked to it.  Generally, if it works and isn’t harmful and those who practice it are blessed by it, then I can see the value in following it.

But when it comes to giving reasons for why you believe something to be TRUE, then that’s a different scenario.  We cannot appeal to tradition in the place of reason to back up an argument.  Therefore, we’re going to have to ‘exercise those little grey cells’ as Detective Hercule Poirot is wont to say:

Hercule Poirot

  • So whether you find yourself abroad, away from your homeland, having to defend your country’s practices
  • Or whether you are asked to give a reason for why you believe what you do about God and the meaning of life
  • Or even if you are asked to justify your choice of a political candidate, your particular diet, method of childrearing or managing a work crew…..

….then it’s best and more impactful to your questioner if you can give a rational reason for what you do.  Besides, the value in examining why you do something might just be in getting you to discard that way in favor of another.  Do you really want to emulate this man?

Tradtion - John Lennon

Logical Gal delights in a new Fallacy

10 Feb

I never knew the Etymological Fallacy existed! But when I read about it yesterday, I saw exactly what it was and how helpful this category is going to be.

Take “sin” for example. The Greek word is ‘hamartia’.  Many Christians have glibly defined this Greek word as ‘to miss the mark’.  How tame can you get? What’s the big deal about lack of skill or lack of practice or ‘woops! – guess I missed’?

But I now know that relying on the original meaning of ‘hamartia’ commits the Etymological Fallacy.  So what if the term originally referred to shooting an arrow off course?  The way it was employed by Jesus and the apostles to teach about sin is what counts.  In that context, sin resulted in death, not the counsel to get more coaching!

So here is how the Etymological Fallacy works.  It doesn’t MATTER how a term was first or originally used at one time, what counts is how it is understood in the current context. A striking example of that is the adjective ‘gay’.  When I was growing up, the jingle for the Flintstones used it in its then-current meaning of merry or happy.  But to cling to that original definition today fails to communicate.  Contemporary usage guides the proper use of terms.

A few weeks ago, I blogged about Peter Boghossian’s disingenuous retooling of the term ‘faith’ to mean unwarranted belief or wishful thinking.  So, too, can we err in the opposite direction and stubbornly claim that we ought to be able to use a definition from times past that is no longer part of the common vernacular.

The whole point of any conversation or written essay is to communicate to others what is in our minds. We have to be careful in how we use a term.

Next Step: What words have YOU puzzled?  Maybe the first step is to consider other possible meanings.  You might be as tickled as I was to find a way to distinguish among the definitions, thus clearing up a concept that has puzzled you for years.

Logical Gal and how kids can benefit from studying Logic

31 Jan

A friend of mine’s daughter has her doubts about the benefit of studying logic.  It’s a required course for 7th graders at her classical school.  The curriculum introduces informal logic in the 7th grade and formal logic in the 8th grade.

Informal logic consists in all the fallacies or bad arguments people use.  Formal logic is the study of GOOD argumentation: its form.

But back to this pre-teen’s question about the relevance of her course of study.  I hear it as a French teacher and I’m sure math teachers have learned to shut their ears to this perennial question:

When am I ever going to use THIS!!!!

Here is how the study of poor argumentation can help anyone, no matter his or her age.  Armed with the ability to identify the fallacies of others, you will be able to stop them in their tracks when they come at you with:

  • …because I said so (Argumentum ad Baculum – Big Stick) – often used by parents!!
  • …because anyone who is anybody does it (Argumentum Populum – Mob Appeal)
  • …because Justin Bieber said they were the coolest running shoes (Celebrity Transfer)
  • …because these puppies and kittens will die if you don’t donate (Appeal to Pity – avoiding looking at other reasons, but relying on emotions)
  • You shouldn’t vote Joe for class president because he’s a nerd (Ad Hominem Abusive- attacking the guy’s character instead of looking at his platform)
  • You can’t trust what the disciples said about Jesus.  After all, they lived with him for 3 years (Ad Hominem Circumstantial – they must be biased)
  • You can’t tell me not to smoke because YOU smoke (Tu Quoque – you do it, too!)
  • You can either clean up your room now or before dinner. (False dichotomy – there are other times) again, a favorite of parents.
  • If you don’t let me have a cell phone at age 12, then I’ll never have any friends! (Strawman – reframing someone’s position incorrectly)- a favorite of kids!

These are just a few of the more common poor arguments or fallacies that swirl around us all the time. Can you see how useful it will be in giving both the adolescent AND the adult the key to identifying manipulative reasoning?  Even if you don’t remember the name of any of them, once you understand the thinking behind each, they are super easy (and fun!) to spot.  All you have to do, when someone tries to lay one of these babies on you,  is come back forcefully with,

That’s a fallacy!  

Try your hand at spotting what’s wrong in this argument!

How did you do? At least you could probably FEEL that something was wrong.  It’s invalid because of the Fallacy of Equivocation.    In this case, the word ‘headache’ is used equivocally, that is – in two different senses, thus creating the fallacy.  Equivocal words refer to two different concepts.  Both a pain in one’s head and an annoying condition can be called a headache.

Finally, the one fallacy I, as a parent, would want my child to have down pat before launching out on his or her own would be the Fallacy of the Non Sequitor.

If you have a daughter, think of a guy trying to get her to indulge in casual sex with him.  He lays this line on her: “If you love me, you’ll sleep with me!”

That, my dear readers, is an example of something that does not follow, hence a NON SEQUITOR.

Or how about this: “Why not try these drugs, you’re only young once!”

In both cases, there is absolutely NO CONNECTION between the first premise and the second.  Our children need to know HOW to respond before they are faced with the absurd and sinful choices, which will surely be thrown at them.

Question: Which fallacies have you succumbed to?