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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)

 

 

 

 

The power of a conclusion

8 Feb

It’s never too late to begin to parent well.

Even if you have been a poor father and raised 10 ungodly sons.

My husband and I were marveling the other day at Joseph’s unwavering faith displayed while a slave in Potiphar’s house and then during subsequent years stuck in that Egyptian prison.

Unlike Great Grandpa Abraham, Grandpa Isaac or Dad Jacob, Joseph neither saw nor spoke with God or His angels.  But God’s hand rested on him.

  •  Genesis 39:2-4 The Lord was with Joseph, and he became a successful man, and he was in the house of his Egyptian master. His master saw that the Lord was with him and that the Lord caused all that he did to succeed in his hands.

What happened to Joseph that set him apart from his wicked, ungodly older brothers?

Here’s my theory:

Genesis 34 narrates the account of Dinah’s rape by one of pagan Shechem’s local boys. Father Jacob does nothing.  His 10 older boys take matters in their own hands and brutally revenge their sister’s honor.

Jacob had not exercised any godly influence on his sons that we can discern. After this dark chapter of family history, he could have concluded:

  • I have failed as a father for I have NOT raised my sons to know the Lord
  • Therefore, I’m a terrible father.  That’s just who I am.

I don’t think Jacob indulged the human inclination toward self-pity and paralyzing remorse.  I think the nadir in his life marks a turning point in his resolve and behavior.  What’s the evidence?  In Genesis 37 Joseph shares some startling dreams about his brothers bowing down to him.  Then during his Egyptian captivity, dreams play a major role in his deliverance.

Maybe Jacob came to his senses after the Dinah tragedy and began to take his father role seriously.  I can picture him spending hours relating all he knew to Joseph and Benjamin about Abraham’s adventures with God and then their grandfather Isaac’s experiences on Mount Moriah with the sacrificial ram swap for his own life and then how he prayed for their grandmother Rebekah to get pregnant. And then his, Jacob’s, very own encounters with God.

He would have dramatically narrated the ladder dream with angels descending and ascending to heaven, which occurred the first night on his outward journey to Uncle Laban’s. Then God spoke to him, directing him to lead the entire clan back to Canaan.  He would have explained the ‘genesis’ of his perpetual limp, trophy won during the famous wrestling match with the Angel of the Lord.  Joseph and Benjamin would have begged to hear yet again how God spared them all when Uncle Esau met Jacob’s approaching gaggle of people and herds with a small army of 400 men!  Jacob had feared for all their lives and strategically divided everyone into smaller groups.

Yes, Jacob must have drawn a different conclusion after his last parenting failure, one that changed the course of history.

Yes, he had mostly abdicated his responsibility to teach his family about Almighty God. But, he could change and perhaps influence the two remaining boys. There WAS something he could do. It wasn’t too late.

My scenario is speculative.  Yet, there is no question that Joseph WAS different from his brothers.  His character turned out to be pivotal for the family, for the Hebrews and for the world.  Had he not heard about the family’s God encounters of years past and learned about the character of God, he might not have been open to the dreams God gave him. There possibly would have been…….

  • No bragging to his brothers
  • N0 fuming jealousy that turned murderous
  • No enslavement in Egypt
  • No ruling in Egypt
  • No rescue from famine
  • No fertile cocooning in Goshen
  • No population explosion
  • No miraculous departure
  • and on and on all the way to NO birth of the Messiah in the tribe of Judah, as predicted

Why was Joseph different?  As my husband pointed out, the Bible is silent on how he learned about God, but God was clearly with him during his 13-14 as a slave/prisoner.  He worked diligently with skill and rose in the ranks wherever God planted him.  We read of neither moping nor complaining.  He strove to serve those around him, whether as a household slave, a helper to the prison boss or the number two ruler in Egypt.

My point is this: what we conclude from past failures affects the future.  What encouragement.  And what a warning about drawing the WRONG conclusions.

It’s NEVER too late to change.

Gospel logic

18 May

God is able to make all grace abound to you that always having all sufficiency in all things, you may have an abundance for every good work. 2 Cor 9:8

I sometimes struggle with feeling as though I have SUFFICIENT time to do what I want to do – read during a period of the day when I am most alert.

So anytime I hear mention of the concepts of ENOUGH or SATISFACTION, which both can be described as contentment with the current supply, my ears perk up.

The other day, I was thinking about how  I might logically frame my feeling of sufficiency. Here is an initial attempt:

Premise 1: If I have all sufficiency in money, time and health, I am content

Premise 2: God has said that He is able to provide me with complete sufficiency

Conclusion: I should be content because I have access to my sufficiency by asking Him regularly for what I need

If the above reasoning is true, then why might I still struggle with a sense of lack or not enough?

Immediately the Holy Spirit reminded me of the PURPOSE for which God promises to provide me sufficiency.  Not primarily (so it might seem) simply to please myself, but instead to do the work that HE has planned for me to undertake.  In Ephesians, Paul reminds us that we are raised from the walking dead to being alive in Christ to undertake and carry out the works that God has planned for us.

For we are His workmanship, having been created in Christ Jesus for good works which God prepared beforehand that we should walk in them. Eph 2:10

(an aside, the Greek word for workmanship is poiema which some have rendered as ‘poetry’)

Okay – so when God gives us grace that translates into sufficiency, He says that it is not for our good pleasure (my reading), but to do the work that He has pre-ordained for us.

Hmm…is that disappointing?  Well, ça dépend! (that depends, as the French say).

Jesus said: My food/meat is to do the will of God who sent me and to accomplish His work – John 4:34  And food is the Greek word broma which means:

  • aliment which refreshes, delights or truly satisfies the mind

It seems that God is VERY efficient.  He has so created work both to accomplish His purposes AND to refresh me. I can be assured that looking to God the Father for what will ultimately satisfy me involves letting HIM assign and organize the work I am to do.

Left to please myself, I might think what I crave for restoration are the time and energy to READ.  But I am beginning to see that maybe I am not wise enough as the created being to know what is best for me.

I’m slowly learning to depend on my Maker to know what kind of high-grade octane nurtures, protects and optimizes my spiritual engine.

high octane

Logical Gal muses about naturalism and homosexuality

6 May

When was the last time you walked a premise or position as far as you can, applying with consistency all aspects of the ‘stand’?

I’ve been thinking about naturalism, that way of describing our universe as a closed system. Built into this worldview is the fundamental belief that nothing exists beyond the natural or physical. I’ve also considered the theory of evolution.

I’m not a scientist, but what I understand about evolution is that organisms reproduce but sometimes with random mutations – a descent with modification.  If the change promotes self-continuation, also called being ‘good’ for the species, then the change continues.  If the change weakens the species in some way, systems that promote ‘survival of the fittest’ kick in. This built in self-regulatory guidance is a way to explain how nature will take care of ‘mistakes’.  And these ‘mistakes’ are just the changes that turn out to be not ‘good’ for the species.

Evolution thoughts

As you might attest yourself, claiming that something is ‘good’ all depends on what you mean by the concept of ‘good’.

It USED to be that most folks could say without pause that ‘good’ or ‘bad’ fell into the arena of ethics and philosophy. Aristotle wrestled with what constitutes our highest good and how that plays into virtue, especially excellence. And Judaism and Christianity have long defined ‘good’ as aligning with God’s character.  Our Creator is good and He created us in His image to BE good as well.

But according to atheist Sam Harris, the concept of ‘good’ is more akin to an effective chess move, a change that will win the game.  So in baseball, to say that a batter is ‘good’ would be a way of describing his ability to hit the ball so as to bring in the most runs.

This idea of what I’m calling ‘natural goodness’ (as opposed to ‘ethical goodness’) has some interesting ramifications for the theory of evolution and the phenomenon of homosexuality.

I want simply to raise a few questions.  Addressing them will take more time.

  • If the process of evolution envisions species self-optimizing, then how can homosexuality be good for the species?
  • Isn’t reproduction the goal of a species?
  • And if species survival IS critical, then why are certain 21st century societies willingly bringing on ‘PAN-upheavals’, that downplay the propagation and nurturing of the next generation?
  • How many Americans are actually gay?

Just a quick on-line search produced reports that document a lower-than-thought percentage. Studies show that in fact only 2 % of the US population self-identifies as gay, although some have dabbled in same-sex attraction. Link to Atlantic Monthly article

Final question:

  • How can naturalists and those who support the theory of evolution maintain that promoting homosexuality via mandated government policy is GOOD for a society, since it doesn’t encourage the continuation of our species?

Just thinking…..

Supreme Court