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Prayer logic

4 Jan

You do not have, because you do not ask.  James 4:2c

I’ve been listening to archived John Piper sermons on prayer.  The Bible’s stunning truth about prayer hit me afresh this morning.

We don’t understand WHY the all-powerful God, the One who created every visible molecule in the universe as well as everything that is invisible, says He waits on us to ask. Only that He DOES…command that we pray, that we ask Him for what we need and want.

Note to Maria – Don’t spend any energy chewing on the bone of how come – just revel in it. The fact that He who created all things at His command should invite us to participate with Him should STUN us!

After we pick ourselves up off our face, we should then focus on the truth that James announces.

But an obvious question emerges if we try to formulate James’ truth claim into a syllogism in order to think it through. Do we apply James’ statement universally (ALL versus SOME) or as referring to a particular group of people?  Here’s what it looks like when I write it as a universal truth.

Premise 1: ALL people who lack something are people who don’t ask God for that item

Premise 2: You are a person who doesn’t have something

Conclusion:  Therefore, you are a person who doesn’t ask God

Hmm, does that logic square with how you have experienced reality so far?  Are there situations in which you have prayed to God and have yet to receive?  Or conversely, has God given you gifts for which you didn’t ask/pray?

I think all of us can attest to circumstances when despite LOTS of prayer God has not supplied the healing, the job, the baby, the money, the spouse or the resolution. As well as times when He ‘out of the blue’ graced us with a surprise blessing, both unanticipated and unasked.

In analyzing the above syllogism, we would say it is logically valid, that the premises are laid out in a correct order, but the conclusion is not true. Why?  because the subject in Premise 1 falsely includes ALL people in the world.

If we exchange the universal quantifier ‘ALL’ for the particular quantifier ‘SOME’, then we might get closer to the Truth.  Let me show you what that looks like and then we’ll talk about it:

Premise 1: Some people who lack are those who don’t ask God to provide what they need/want

Premise 2:  You are someone who doesn’t have what you want

Conclusion:  Therefore, you are someone who hasn’t asked God to provide

Again, that conclusion is not true in every situation.  To wit, I have repeatedly asked God to give me a different job.  And He hasn’t, YET……

So just using one circumstance in my life as a counter-example, I can prove that the conclusion in this second syllogism is not true.  It’s also not valid.  Why?  Because the conclusion overreaches the facts given in Premises 1. This first or major premise describes only one of two categories I’m going to call ‘LACKERS’ – those who haven’t prayed.  There is the category of ‘LACKERS’ who have indeed asked God for what they want.  So even though Premise 2 is true (you don’t have what you want) we can’t be sure which group of ‘LACKERS’ you fall into.

Bottom line?  I don’t know why God hasn’t answered my many prayers, YET.  But I do believe the Bible is authoritative.  I know that God commands us to pray.  I also know that He is good.  So there I rest AND I will continue to pray. What about you?

Logical Gal and when making sense is not enough

21 Jan

Makes sense

That makes sense to me!

Have you ever heard that comment or uttered it yourself?  It sounds so innocent, doesn’t it!  Don’t we want to make sense of the world around us – especially in light of all the horrors and issues that DON’T make sense?

It’s human nature to try to identify, draw associations and categorize all the information that cascades into our consciousness, moment by moment!

But, we must not forget that just because something makes sense, that detail does NOT make it true!

I ran across a useful example of this faulty thinking the other day.  While listening to a radio program broadcast by the organization Stand to Reason, the host discussed how to deal with the possibility that scientists might very well indeed find a gene marker held in common by some gay men and women.  The presupposition explored by the host is this:

Whatever makes sense is right or must be true.

The caller who holds to the above assumption suggested the following opening to an argument based on that assumption:

  • If there is a ‘gay gene’, then it is natural for those with that gene to want to/ need to engage in what is ‘natural’

After having suggested that line of thinking, he finished his explanation with the comment, “Makes sense to me!”

The host, Greg Koukl, reminded listeners that JUST because something makes sense, that doesn’t make it true or right.   An argument based on the faulty assumption could be stated like this:

P1 – All that makes sense is right

P2 – Doing what is natural makes sense

C – Therefore, doing what comes natural is right

And going on, one can continue:  Given a ‘gay gene’, then it is only natural that those with this gene engage in the behavior that is part of their inherited disposition.

However in the above argument, although it may be rational and correctly formed, it can still be faulty if one or both of the premises are FALSE.  Take a look at the following obvious example of a valid, but unsound syllogism:

P1 – All things with 4 feet are alive

P2 – This table has 4 feet

C – Therefore, this table is alive

Why is this argument valid?  Because it follows the rules of formal logic.  It makes sense, we could say. But you don’t have to be a rocket scientist to tell that something is WRONG!!!

Bingo!  The faulty premise is the very first one.  NOT all things that have 4 feet are alive, only SOME.  So the universal statement needs to be changed to a particular statement to be true.

P1 – Some things with 4 feet are alive

P2 – This table has 4 feet

C – Therefore, this table is alive

Soundness Venn diagram

Let’s get back to the possible research into gene markers and whether doing what is natural makes sense.

  • Besides the unsoundness of the argument due to the faulty 1st premise..
  • Besides the false nature of the underlying presupposition that What makes sense must be so,

There is ALSO the assumption that could be debated:  We should engage in what comes naturally!


Question: Which ‘natural’ scenarios come to mind that raise a red flag?



Logical Gal and why your major premise matters

20 Jan

Premise 1 – All exercise benefits the body

Premise 2 – Stretching is an exercise

Conclusion – Therefore, stretching benefits the body

The major premise is the first one listed above, in this example:  All exercise benefits the body

The way deductive logic works is this: if the major and minor premises are TRUE and if the syllogism conforms to rules for correct formation (validity), then the conclusion is both predictable and true. Without going into any further discussion about validity, I want to focus on WHY one’s major premise, in general, can have a weighty effect on one’s conclusions.

Consider a married couple who trust each other.

Let’s imagine a situation where it’s reported to the husband (Bob) that his wife has been seen having some tête-à-tête discussions with a man.  The implication is that maybe the wife (Sue) is having an affair.

Depending on Bob’s major premise about his wife and their marriage, his conclusions will be different.

Possibility # 1:

Overarching presupposition or major premise:

Premise 1:  (overarching major assumption) My wife is faithful to her word and her commitments and loves me completely

Premise 2: (the circumstances) – But she has been seen with another man

Conclusion: since I know that she is a faithful gal and loves me, there must be a good explanation for who that other man is.

Here’s the other major premise and subsequent conclusion

Premise 1: My wife might not be totally committed to me or to our marriage

Premise 2: She’s been spotted talking with another guy

Conclusion: She probably is cheating on me

Do you see how what we do with new information depends on the contexts we hold?  Same circumstance in both cases – the wife is seen meeting with another man.  The conclusions vary due to the original major premise or pre-supposition.  Sometimes we are not even aware ourselves of the assumptions we carry with us.  They are implicit, subconscious.  But they powerfully affect our lives!

Just for fun, what could be possible scenarios that would explain Sue’s conversations with a strange man? Maybe she was talking….

  • with a craftsman to plan a special birthday gift for her husband
  • with a potential care-giver for her aging father
  • with their son’s new soccer coach about his skills

If we move into a more spiritual plane, how might our pre-suppositions about God affect our reactions and conclusions to disappointment, illness or acts of violence we encounter in life? Have you ever met someone who claims that God must not be good or all-powerful if He lets evil happen?

Their major premise probably goes something like this:

God is good and almighty if He answers my prayers according to my desires

Question: Have you ever drawn a conclusion about someone or something that turned out wrong? How did your assumption or major premise impact your conclusion?

Logical Gal extols “First things, first!”

14 Oct

The wisdom and simplicity of ‘First things, first’ hit me like a ton of bricks.

I was listening to a discussion between a Christian and an agnostic/atheist.

The non-Christian started to list many evils done in the name of Christ.  The Christian graciously stopped him with this simple question: “Before we look at both the good and the bad actions of those who call themselves Christians, would it be okay with you if we look first at the claims of Christianity?  After all, Christians affirm many different events and statements about a historical man in 1st century Palestine who claimed to be God.  If those claims don’t prove to be true, it’s a certain waste of both your time and mine to go any further in our discussion.”

How brilliant is that!!!  And it’s logical.

Peter Kreeft, in his book Socractic Logic, describes what he calls ‘three aspects of reality’: terms, propositions and arguments. Remember that terms are either clear or unclear (ambiguous), propositions are either true or false and arguments are either valid or invalid.

So, in keeping with the ORDER of logical thought, we need to determine the truth or falsity of  propositions BEFORE we start to proceed via argumentation into implications.  Claims are going to be either true or false.  They can’t be both and there is no other alternative.

My impatience to jump into explaining my point of view has cost me frustration AND time.  And no doubt I have used up much good will in certain relationships.

Employing simple principles of logic and clear thinking benefits all of life!

To take vitamins or not, that is….not the question today

2 Sep

Imagine that your office mate has just asserted the most ridiculous conclusion that you have ever heard: that taking vitamins is a waste of time and money!    

    VERSUS ………….    

You, who pop a handful of carefully selected ‘food supplements’ SWEAR by the efficacy of these expensive pills.  After all, how many sick days have YOU taken in the past five years?

But before you give her a piece of your mind, calm down and ask her to explain her claim.  Remember that she who advances a proposition, a claim, a conclusion, an assertion MUST give her evidence, her reasons, her method of arriving at this thought.  If you want some help, click on the link here for a resource by Greg Koukl.  Great Book to Help who does what in an argument

After listening to your office mate, you realize that before you can even GET to thinking about the truth or falsity of her conclusion, you have to guide her in formulating her reasons.  After some coaxing, here is what she has offered:

  • Food provides enough vitamins and minerals to stay healthy
  • No manufactured vitamins can provide the same quality of benefit found naturally in food.
  • Therefore, taking vitamins is a waste of time and money

Your friend obviously needs some help in identifying her terms and organizing her argument into syllogisms that are built on 3 terms each.

But before you pull out your pencil and start sketching logic charts, we can just refer to Rule # 7 to show that her argument is invalid:

What is the quality of premise # 1 (‘food provides enough…’ )?   It is AFFIRMATIVE

What is the quality of premise # 2 (‘no manufactured…’)?  It is NEGATIVE

Rule # 7 of the Seven Rules for Testing Validity states that if one of the 2 premises is negative, then the conclusion MUST be negative.  Your friend has NOT stated a negative conclusion but the AFFIRMATIVE statement that ‘Taking vitamins is a waste of time and money’

Since the argument is invalid based on Rule # 7, you’re off the hook from giving your 2 cents worth.  But spend some time helping her tease out her reasons and re-articulating them and then checking to see that is what she means.  She’ll gain respect for you as a gentle friend and maybe SHE might see some holes in her reasoning.

Meanwhile play around with what YOU believe about vitamins and craft YOUR argument following the 7 rules.

Here they are in summary.  Next time we’ll build an argument about vitamins that is VALID.

Every syllogism to be valid (that is correctly formed), must comply with all seven rules:

  1. Has 3 and only 3 terms
  2. No middle term in the conclusion
  3. If a term is ‘distributed’ in the conclusion, it must be ‘distributed’ in one of the premises
  4. The middle term must be distributed once.
  5. No conclusion can be drawn from 2 negative premises
  6. If the 2 premises are affirmative, the conclusion MUST be affirmative as well
  7. If one of the 2 premises is negative, then the conclusion MUST be negative as well.

Keep thinking! 

Gotta stay positive

28 Aug

All Chocolate is satisfying

Ghirardelli is chocolate

Tf, Ghirardelli is not satisfying   

What???  That doesn’t make sense!

You’re right.  Our mind easily balks because Premise 1 and Premise 2 are both affirmative propositions, they are A statements.  And the senseless conclusion is a negative proposition, an E statement (No Ghirardelli is satisfying).

Below is the chart that shows the 4 kinds of propositions and their Quality (Affirmative or Negative)

Affirmative  Propositions                      Negative Propositions

in this column                                         in this column

A – All dogs are cuddly E – No dogs are cuddly
I – Some dogs are cuddly O – Some dogs are not cuddly

So, back to chocolate and the question of validity – We are continuing with our extended lesson of

  • “How to examine a syllogism and see if it’s valid”

There are 7 rules in our Validity Checklist that we must run down to determine if a syllogism is valid , that is, in the correct form.  Last time, we showed that NO conclusion whatsoever can be drawn from 2 negative propositions.  Today, we see from Rule # 6 that

  • if premise 1 & 2 are affirmative, then the conclusion MUST be affirmative as well.

So what happens if someone has asserted a negative claim about health care such as:

  • No costly plans are possible

and when you ask the person WHY??? (Whoever makes an assertion is required to back it up with reasons) he/she says:

Premise 1 – All government plans are possible

Premise 2 – All costly plans are government plans

They’ve JUST articulated two affirmative reasons for their NEGATIVE conclusion of “ No costly plans are possible”

Before you jump in (or down your conversation partner’s throat) and start giving YOUR reasons why you disagree, you have every right to encourage this person to explain what she has either

  • left out on purpose
  • left out because she is not THINKING

Remember, there is absolutely NO point in arguing about an invalid argument.  And a negative conclusion drawn from 2 affirmative premises is one of the 7 ways an argument can be deemed invalid.

An argument (syllogism) must win the ‘Good Logician’s Stamp of Validity ‘ to be considered ready to meet the next criterion – are the premises TRUE.

Two negatives make NOTHING!

26 Aug

         No boys like me

                                        Some of my best friends don’t like me

                                        Tf, my life is awful

What’s wrong with this argument?

-besides being the lament of a ‘too-introspective’ teen girl

-besides consisting of more than 3 terms (violates Rule # 1 of the Valid Argument test)

Here’s what’s wrong – You can’t draw ANY conclusion WHATSOEVER from 2 negative premises.

That’s Rule # 5  for “Evaluating the validity of a syllogism” in a nutshell.

Rules 1 to 4 have focused on

  • the number of terms in a syllogism
  • the occurrences of each term (Major, Minor and Middle) in a proper syllogism
  • the ‘distribution’ of each term, that is –  the reach or how many ‘members in a set’ to which each term applies

With Rule # 5 (there are seven in total), we look now at what is called the QUALITY of  the premises in the syllogism.  Quality refers to whether a proposition is affirmative or negative.

Both common sense AND logic inform us that you can’t get ANYTHING positive out of a negative.  And if you can, then there is more ‘back’ argument that needs to be flushed out (unarticulated pre-suppositions or other propositions).

Imagine someone stepping outside of his office cubicle and shouting seemingly à propos of nothing…..

-the picnic is not going to happen!   

-there is no pizza in the freezer!

– therefore, I’m happy

We’d conclude that this guy was nutty!

So what do we do when we run across an argument in a letter to the editor that is drawing an affirming conclusion from a bunch of negative ‘facts’ – that is, when their premises are either E or O statements?     

(E – No pizza is in the freezer; 0 – Some picnics are not going to happen)

First of all, since we are equipped with logic as a tool, we know to ask for more information.  Their claim, constructed from 2 negative premises, can’t stand on its own.  There HAVE to be affirmative propositions (A  – All food is what makes me happy; I – Some meals are better than no meals).

Don’t be afraid to gently push back against an argument-maker by asking questions.  After all, the burden of proof is on him who makes the claim.

And by the way, this is an easy way out of an argument you might not want to tackle.  If you can point out gently that someone is basing their argument on negative premises, you don’t even HAVE to consider the conclusion – it’s irrational to begin with!