Tag Archives: Enthymemes

How do you know you exist?

13 Jul

Penseur  The math whiz and philosopher, René Descartes, sought to clarify his doubt and his knowledge.  So he pushed back as far as he could to what he could know for sure.  Most people can quote part of his argument:

I think, therefore I am

As many of you know, he left out the major premise.  No ‘doubt’ that it resided in his mind, but seemed too obvious to mention.  That’s the nature of an enthymeme, an unspoken premise or conclusion.

For example:

Sally pipes up with enthusiasm: I invited our neighbors to join us this Saturday for a picnic in the park!

Sam responds sourly: Great, now we can count on it raining this Saturday!

What’s the unspoken premise?

  • It always rains when we plan a picnic in the park!

Back to Descartes and his implicit assumption supporting ‘I think, therefore I am’

It has to be: All creatures that think exist.  So the complete syllogism would look like this:

P1 – All who think are

P2 – I think

C – Therefore, I am

What brought to mind Descartes’ foundation for knowing or epistemological basis for knowledge was a different origin for the assurance of one’s existence.

While listening to a podcast, I heard an African Christian talk about what anchors him in life. He talked about community as being this source.  He explained:

  • Because the community is the primary building block of humanity, each of us derives his or her own sense of self

His enthymeme would go like this: We are, therefore I am!

And by fleshing it out with the implicit major premise, we have:

P1: If there is a communal unit, then individuals can fully have their being

P2: There is a community in which I a recognized member

C: Therefore, I exist as a full human being

Thinking about and contrasting Descartes’ individualistic enlightenment view with this African brother’s sense of himself as part of a larger group strengthened my growing view that it is not good for man or woman to be alone.  After all, the one true God is a community of 3-in-1, a Triune Happy Godhead.  And if we are made in His image, then to feel fully alive and to function with health, we need to anchor ourselves in community with other people.

I need not be intimidated by famous thinkers and learned philosophers.  The simplest of men and women often are the wisest.


More than one way to solve a problem

15 Jun

My purse was too small.  So I did what all illogical women do, I bought a new purse.

That wouldn’t have been too poor a decision except for 3 factors:

  • I loved this leather, back pack-type purse
  • My husband had given it to me about 5 years ago as a ‘just-cuz’ present
  • I’m a one-purse gal

I keep standard items in my ‘daily essentials-carrier’ like:

glasses, checkbook, wallet, EXTRA card carrier for all those preferred shopping relationships, notebook, almonds, a foiled 3-oz tuna pack, round Eos lip balm, business cards, spare batteries, pens, the other car’s spare key and a bulky makeup pouch with all the emergency supplies one might need.

What I love about the purse is that it’s a hands-free bag one can sport as a small backpack or sling over the shoulder.  Not to mention also that it is leather and minimalist.

But it’s TOO small (there’s always a price to pay, isn’t there!).  There’s only one way to arrange the above items so that all fits as efficiently as possible.  And several times a week, I seem to need something from one of the bottom residents.  Which means I need table space to take everything out, retrieve the item and repack.

Thus far my logical thought process:

Premise: My purse is too small

Conclusion: Therefore, I need a larger bag

I’m always checking out purse selections when we happen to be in a store, which is not all that often.  So last week I was delighted when I just ‘happened’ on a selection of purses at a hiking/outdoor store while returning an item. There was a backpack-style bag, maybe a fourth larger than my daily ‘porte-stuff’. Perfect, I thought.  Since it was early in the new month, I decided I could spring for this spontaneous purchase. But I knew what I must do if I wanted to remain true to my values.  As an aspiring minimalist, I have taken on the rule of “Bring a new item into the house – Eliminate the old item”

What I had not counted on were two unintended consequences:

  • my husband was shocked AND hurt that I threw out the old purse he had given me
  • the larger purse just didn’t slide on as easily as my old one and seemed less secure

I ruminated for 24 hours and then voilà, the lesson from the  Elevator Problem Story hit me.  Malcolm Gladwell had written about this in one of his books.  Apparently elevators moved too slowly for those waiting to board on different floors.  When design engineers were assembled to brainstorm about increasing the speed of elevators in a multi-storied building, one young maverick re-identified the problem.  It wasn’t that the elevator moved too slowly, but that people grew bored waiting!  I’ll let you click on the above link to read his accepted solution that worked and cost far less to implement.

The point was, I had incorrectly concluded that I needed a larger purse.  If we revisit my so-called logical syllogism from above, you’ll notice there is only one stated premise:

Premise: My purse is too small

Conclusion: Therefore, I need a larger bag

A 2nd premise is missing, thus what is written is an ‘enthymeme’, an argument with an unstated premise or conclusion.

In my mind, I thought there was only one possible premise:

Premise 1:  If one’s purse is too small, then one needs a larger bag

Actually, it’s not that I was incorrect about that premise, but that the premise was not complete!

My Eureka moment came from realizing that I had mis-diagnosed the problem.  It wasn’t that my purse was too small, but that I thought I had to fit all those items into it.  My ‘essentials’ had not even been up for re-evaluation.  My pre-supposition had been this: All that my purse currently carries is essential. As soon as everything was back on the table, so to speak, it was clear that I could pare down what I carried every day.

So with some quick and honest tallying of how often ’emergencies’ arise and the substitution of a less-bulky loyalty card carrier, I eagerly ran to the trashcan outside and retrieved my oldie but goodie beloved friend.



Here is my completed premise that brought about my happy result:

Premise 1: If one’s purse is too small, one can remove some items or secure a larger bag

This logical gal needs some more practice in applying reason to everyday ordinary problems!



Logical Gal at the movies

13 Aug

AI the movie

We’re enjoying re-watching some ‘thinking’ movies from the past.  Once you’ve screened a film for the plot line, you can go back and catch the deeper layers. AI or Artificial Intelligence has some dialogue worth pondering.

David is a proto-type robot child who is programmed to ‘love’ after a bonding sequence his ‘Mommy’ (human who owns him) initiates and follows. He responds to her eyes, voice and actions with uncanny human-like qualities that mimic true affection.

In one scene David  is challenged by the family’s REAL son to cut off a locket of Mommy’s hair.  The guile-filled biological boy frames it as a game and orders David to play. We follow the innocent David sneaking into the parents’ bedroom, scissors in hand.  The suspense builds to the predictable moment when Mommy wakes up in horror to see David with sharp edges in hand hovering over her face.   But in momma-bear mode,  she attempts to soft-pedal the event when the horrified dad comes out with this logic:

If he can love, then he can hate!

And after one more innocent event that casts David in a false light, the dad makes the decision to rid themselves of this too-advanced tech addition to their family.


Let’s practice some clear logical thinking by taking the dad’s announcement above and analyzing it.  This exercise will reenforce what we should do ANY time we encounter someone’s position which doesn’t seem quite right.

So what do we have in the dad’s pronouncement?

  • a conditional major premise, what we call an ‘If, then’ statement.
  • an enthymeme – one explicit part of an argument or syllogism and 2 missing parts that our minds fill in easily.

Here’s the completed argument:

Premise 1 (the major premise):  If David can love, then he can hate

Premise 2 (the minor premise): David has shown that he can love

Conclusion: Therefore, it is logical to believe that David is also capable of hating

There’s a law in logic that goes like this:  if the first 2 premises are true, then the conclusion MUST be true in a valid argument (valid means that the argument is in the correct form) 

The above syllogism IS valid because Premise 2 affirms the first segment of Premise 1 (called the antecedent). I ask you, then, is this analysis cut and dried?  Are the two premises true?

Well, the movie clearly demonstrates that David loves.  He is a machine.  He is programmed and built to act lovingly and to have that love increase (grow) in response to his one human ‘bondee’ (one human who initiates a short programmed sequence of words enters into a ‘bonded-for-life’ connection with the ‘mecha’ i.e, the robot).  In the photo below, Mommy places the fingers of one hand behind David’s neck and reads a sequence of words, cementing the bonding.

Bonding between David and Monica in movie AI

But the error in Premise 1 lies in its presupposition.  The dad has humans in mind when he assumes that love and hate go hand in hand.  And for those created in God’s images, id est all of us, that is true.  We have been given a certain degree of free will.  We GIVE our love and we RETAIN or hold back our love.  Or else it is not true love. (What a risk God took! But He evidently WANTS the pinnacle of His creation to love Him freely). The downside in creating a machine that imitates a loving human is that the owner of the ‘mecha’ deceives himself in thinking the machine really DOES love him. If he stops and THINKS, the machine is merely following a program, however complex it may be.

David loves Mommy, acts and speaks with tender, servant-like affection because he can do nothing else.  This is not true of humans.


Let’s shift back to real life.  Deep movies are satisfying because they offer us food for thought.  We can practice our logic skills in a safe environment when we discuss a film’s premises and conclusions.  Then we feel more prepared gently to question someone in our circle who advances a conclusion that might not be sound.

Vive le cinéma profond!

Question:  What is your all-time favorite deep movie?  What is a premise we could analyze? 

Logical Gal and Syllogisms everywhere

7 Apr

Bird Syllogism

I don’t always see what is right in front of my eyes.  It’s that common experience that occurs when you notice what was present  all along.

Today I was reading the last sentence of the book of Judges in the Bible.  It goes like this: There was no king in Israel.  Everyone did what was right in their own eyes.  (Judges 21:25)

The commentary mentioned that the author of the book meant to communicate Israel’s need for a king who was powerful enough to enforce God’s laws.  Had I not read that explicit conclusion, I would NOT have connected the 2 sentences: a) no king b) chaos as people live life as they please.

My first response to the commentary is ” Well, duh!  Thanks for bring this to my brain’s attention, because my brain (ever in self-protective filter mode) had not seen the connection.”  As it turns out only when there is extra LIGHT given to some facts do we notice the details, the nuances, the relationships.  I had read that passage numerous times.  It is also an oft-quoted observation of errant people wandering far from God.

I mentioned that thought to my husband and he responded, “Well, there’s a syllogism, for you!”  And his addition of critical thinking brought more light!  Here was a 1st degree enthymeme.  What was missing was the major premise.  The Judges passage stated the following:

  • the 2nd or minor premise – No king in Israel was reigning and enforcing the Mosaic Law
  • the conclusion – Therefore, no people followed the Mosaic Law but did what they wanted

It was then easy to construct what HAD to be the 1st or major premise:

  • All kings in Israel reign and enforce the Mosaic Law

Mosaic Law (10 Cs)

Once you know the structure of a syllogism,  you can spot arguments in toto or in fragments.  Understanding the structure not only gives you a sense of where an argument should go, it also provides NEW information that might not have been so apparent at first glance.

Ah, the usefulness of logic!



Logical Gal and the difference between objective terms and subjective values

4 Nov

Last time I wrote (post dated 1 Nov 2013),

I asserted that terms were by nature objective since they are descriptive of what is.

One of the laws of the universe (no human made this up) is called the Law of Identity.  An apple IS an apple.  All the attributes on the left of the IS add up perfectly to what is on the right side.   Add or subtract one of the attributes and you no longer have an apple.

I asserted that the definition of TRUTH is straightforward – It is that which corresponds to reality.

So where do values and opinions come in to play?  Can they be subjective?

Value statements depend on the presuppositions behind them.  Presuppositions are the assumptions we make that are often hidden.  But they totally influence our conclusions, our values!

Change the presuppositions and you alter the sense of the conclusion. Presuppositions are sometimes unarticulated in a discussion.  When you have just a partial argument, it’s called an ‘enthymeme’ because the missing parts are implicit.  

“You’ll get fat!”   when fleshed out could be part of a syllogism that looks like this:

  • Eating chocolate 3x a day causes people to get fat – (Presupposition)
  • You’re eating chocolate 3 x a day – (Presupposition)
  • Therefore, you’ll get fat – (explicit enthymeme that showed up just as conclusion)

Getting fat is a fact, it’s truth.  What I mean is:  ‘adding a pound of fat to your body‘ is what might be corresponding to reality  But again, depending on one’s values, being fat is either a sign of ill health, or a sign of prosperity and beauty. (Think of Rubens’ artwork!)


The fact of adding fat is the truth – it’s objective.

But what it means is relative and subjective to the one creating the proposition.  In the conclusion above, the proposition being asserted is this:  You (subject) are doing something that will cause you to get fat. (predicate)

That proposition is either objectively TRUE or FALSE.

It’s subjective sense is, however, relative…..relative to the assumptions/presuppositions one holds.

Clear thinking requires the use of tools and the time to employ them.  Asking questions and parsing out terms from propositions is one tool.  Teasing out the implicit ideas behind the propositions is another.  Be a diligent detective.

It’s biblical!

23 Sep

“Unlike the welfare state, prostitution is biblical!” –


This final jab by a local newspaper reader’s letter to the editor was meant to snarkily shut down a Republican columnist.  The government minimalist had explained that many conservatives advocate the Bible’s pattern of family and faith communities support for the poor rather than depending on the state to provide benefits.  

The premise ‘prostitution is biblical’ is actually an enthymeme. Remember them?  Those are informal arguments that are missing one or two premises. Usually the parties to a conversation know the missing claims, so the proponent feels that to articulate the obvious would be a waste of breath or ink.

 One sibling to another:  What’s for dinner? 

The response:  It’s Tuesday!   

 What goes unsaid is the following:  ‘Mom always serves meatloaf on Tuesdays, so if today is Tuesday, then we’re having meatloaf!”

In the case of the premise:  “It’s biblical” we can’t be sure of the rest of the argument.  It would be helpful to actually engage with the one who advanced the statement.  But if the proponent is not around to enlighten you, you have to consider what he or she might have meant.

Here’s how one context could be construed:

 All practices in the Bible are commendable behaviors

“Prostitution is a biblical practice” (the comment by the letter writer)

Tf, prostitution is a commendable behavior

The above syllogism IS valid.  But is it true?   

Not at all!  Just because something is in the Bible, does NOT mean that God endorses it.  David committed adultery and arranged a murder.  Abraham passed his wife off as his sister – twice!! – to save his skin.  Jewish religious leaders manipulated the Roman officials to eliminate by execution a problem teacher – Jesus!  Peter turned coward and denied Jesus!  A Jewish man throws his concubine to a frenzied crowd who rapes & kills her; the man then callously cuts her into 12 pieces and sends a piece to each of the 12 tribes of Jacob.  The Bible is, in large part, the history of humankind’s sinful mistakes and the account of how a loving God planned and executed our rescue!  So just because accounts of dishonesty, rape, murder and pillage are biblical, i.e. IN THE BIBLE, that does NOT mean God condones them.  Au contraire!  (They actually offer credibility to this holy book – if YOU were going to make up a religion and its teachings, would you show the seamy side of your followers?)

Here’s the takeaway: when you are ‘bestowed’ an enthymeme, simply ask politely for clarification.  Just what does the argument-advancer have in mind when he or she pronounces what turns out to be an argument only partially articulated?  Make them turn that enthymeme into an explicit argument.


A useful two-letter word

16 Sep

The accusatory screed drips with venom: “Corporate CEOs are all rich!”

Verbal attacks are nothing new.   One can substitute any forcefully-announced statement to clobber YOU who have an opposing view. To wit:

  • ·         Johnny gets to stay up until 10 pm on a school night!
  • ·         The rich aren’t paying their fair share!
  • ·         Fast-food workers can’t earn a living wage!
  • ·         Public school teachers don’t have to contribute as much for their health insurance coverage!
  • ·         Susie’s mom doesn’t have to put up with a lazy child like you!

What is the most effective response to an emotion-laden claim?  The little word:  So?

Don’t feel like you have to fall back to counter arguments that begin like this….

  • ·         My uncle is a CEO of a small book-binding company and he and his family certainly are not rich
  • ·         I know plenty of 3rd graders who have to be in bed by 9 pm during the school week…
  • ·         I happen to know a few ‘rich’ people who pay LOTS in taxes…
  • ·         Maybe it’s not a bad idea for a person to hold down TWO minimum-wage jobs

….instead take a deep breath and say the two-letter word, “So?”  Then pause to listen for their rationale.  What you have just done is give them the space and the invitation to explain to you their unarticulated pre-suppositions.

Last week we began to examine ‘enthymemes’.  That’s a fancy term for an informal argument that is missing one or more premises or even the conclusion.  The unarticulated parts are in the argument-advancer’s mind.  He just didn’t mention them.

·         When someone says, “Shucks, it’s raining!”, that statement is part of a larger argument

If it rains, the wedding ceremony will have to be moved indoors.

It’s raining

Tf, the wedding ceremony will have to be moved indoors.

So, too, with the earlier claims, they are part of an incomplete argument.

When someone condemns CEOs for being rich, this is probably what their argument looks like

Rich people are bad

Corporate CEOS are rich people

Tf, Corporate CEO are bad

Once you help your conversational partner spell out their 1st premise, then you can gently ask them whatever next comes to mind.  I would probably probe by inquiring,   

  • “Why do you consider rich people bad?”
  • Or, “What is so bad about rich people?”

At the very least, you have gotten the other person to THINK. Maybe he or she is just passing on something picked up in the air, on TV or from a friend.  It might not really be what he/she thinks.  You are doing people a service when you take the time to ask them with sincerity what they mean and why they view life the way they do.  And you are showing them THEIR responsibility to have reasons for what they believe.   

Help me, Help me! I’ve been attacked by an “ENTHYMEME!”

11 Sep

A friend recounted a recent example of an attack of ‘unreasonableness’ aka – Where’s the Logic??? in everyday life.  Her conversation at the Eye Doctor’s went like this:

Customer:  What’s this charge?

Optometrist’s Clerk: That’s the “Contact Lens Consulting Fee”

Customer:  But there was no consultation, like last time. Why does it show up on my statement this time, since all I’m doing is ordering more contacts?

Clerk:  Well, you paid it last time!

My friend quickly recognized that she was going to have re-visit THIS bill if she didn’t want to be overcharged.  What actually happened was an improper use of enthymemes!

An enthymeme (pronounced EN-TA-MEME) is an informal argument that has an unstated premise.

We often rely on enthymemes to communicate quickly.  When my husband and his brother were kids, their mom had a routinized supper schedule.  That is to say that she served the same main course on the same weekday each week.  So if you smelled fish sticks, it was probably Friday.   Here’s how a typical conversation progressed:

Steve:  Hey, Bro, what do you think Mom is fixing for dinner tonight?     

Mike:  It’s Tuesday, Dufus, what do you think?

And Steve immediately realized that they were in for liver and onions. Yuk!

So what’s the unstated premise in my friend’s Eye Care office?

  • If we can get you to pay a charge today, you’ll probably pay it next time without batting an eye.

Unfortunately, they and many others probably DO get away with this deliberately deceptive practice.

As the Romans taught:  “Caveat Emptor!” or let the buyer beware!    

But don’t think that ALL who employ enthymemes are trying to pull the wool over your eyes.

As parents, we OFTEN resort to enthymemes to remind our children of what they already know.

Imagine a typical Saturday morning.  Mom is on her hands and knees cleaning the oven when Johnny tiptoes down the stairs headed toward the front door.     

Mom (who has eyes in the back of her head): And where do you think you’re going, Young Man?

Johnny:  To Billy’s house

Mom:  Is your room clean?

Johnny:  silence….(as he turns around and clumps angrily up the stairs.)

What just got communicated was a truthful and very effective and logical corrective with only one premise (# 2)

Premise 1:  On Saturdays, no one leaves the house until they have cleaned their room

Premise 2:  Johnny hasn’t cleaned his room yet

Conclusion:  Therefore, Johnny is going NOWHERE!

When you have someone employ an enthymeme on YOU, you have every right to ask him or her to articulate the unstated premise(s).Then you can challenge the truth if necessary.

Happy thinking!