An Admonition to Avoid Assumptions

It was dusk in the rough town of Chimneysmoke when Rusty and The Kid met. Ever since the Chicken McNuggets incident, they had been mortal enemies. Now they were going to fight it out. “I’ll meet you on Main Street before dark,” The Kid had said to Rusty. “Be there.” He was.

Rusty dove behind a barrel as a missile from The Kid’s gun whistled overhead. “He must be hiding in the shadows by the saloon,” Rusty thought. “I can’t see him, so I’ll have to wait it out.”

Two more shots flew overhead, and then two more. “He’s only got one more shot. I’ve got him now.” When the last round thudded into the ground, Rusty jumped from behind the barrel and rushed for the saloon, gun blazing. Rusty only got as far as the sidewalk when another missile hit him between the eyes. Rusty crumpled up on the ground and didn’t move.

A dark figure emerged from the shadows and sauntered over to the fallen form. “You thought I only had six rubber bands, but this model loads seven,” it said.

As you can see, it can be dangerous to make assumptions. In this story, our character Rusty probably wasn’t aware of the assumption he made – he assumed his opponent’s gun only held six rounds. This is often the problem with our assumptions – we just assume them. An assumption is anything taken for granted, or accepted as true without proof. Sometimes our assumptions get us into trouble.

If Rusty’s thinking had been more deliberate, it might look like this:

1. “The Kid fired six rubber bands at me.”
2. “The Kid’s gun only holds six.”
Conclusion, “His gun is empty. Go get him!”

Unfortunately, the regretful Rusty’s reasoning wasn’t as clear as it should have been. Specifically, he did not question the assumption in #2 and got plugged.

When somebody presents an argument, whether in an essay, a speech, or even a science fair project, he always makes assumptions – some parts which he takes for granted and doesn’t try to prove. Sometimes this is okay. But when we form an argument, we should learn to isolate our assumptions – that is, find out what they are – and then consider whether they are valid. As with Rusty’s example, if we don’t at least know what our assumptions are, then how can we be sure our conclusions are correct?

Learning how to recognize assumptions can be applied to virtually any school subject. The best way to explain is with an example.

Let’s say Rusty is doing a science fair project on “How Music Affects the Normal Behavior of Rats.” Rusty will be exposing rats to 1) classical music, 2) rock music, and 3) no music. Of course, tight funding forces this to be low budget, and Rusty will only use three rats.

The first rat was christened Gus, and he won’t be listening to any music. The second rat was given the name Wolfgang and will be bombarded with the Brandenburg Concerto for eight hours a day. The third, and most unfortunate, was called Elvis, and you can guess what he will be listening to.

Rusty hypothesizes that classical music will help the rat exposed to it, and rock music will make the other rat more stressed.

Rusty kept a scientific diary to record his findings:

“October 12th: Got all rats home. Very excited about project. Began music today at normal volume. No visible effects from the rock music yet – disappointing.

Oct 18: Not disappointed anymore. Test rat #3 (Elvis) showing signs of stress. Grey hairs appearing. Other rats act normal. I continue to play music.

Oct 20: Elvis’s condition worsens. Hair starting to fall out. Amazed that effects of music so pronounced.

Oct 21: Other rats are responding to music. Wolfgang is gaining weight, growing larger, tail longer. Gus sleeps mostly.

Oct 22: It seems my hypothesis is correct. Grey hair is a common sign of stress in many mammals. After only one week, Elvis is mostly grey. It seems rock music does harm the brains of rats by causing them stress. Also, size can be a sign of healthiness. It seems classical music helped Wolfgang – he is much larger than when I started the experiment. Am considering finishing this study and preparing my report.”

Did you notice Rusty making any assumptions here? Perhaps you will see what I mean when I show you Rusty’s next journal entry.

“Oct 22: Never mind. Talked to pet shop. Man says Elvis was five years old – grey hair natural. Caught sister feeding Wolfgang Jolly Ranchers – explains growth spurt.”

Rusty is making two assumptions here. First, Rusty is assuming that any changes in the rats after he starts the music is a result of the music. In other words, he assumes that all three rats were exactly the same when he got them and the only difference between them now is the music and its effects. Is this a warranted assumption? No, as you saw, his rats had unknown and varying influences.

Rusty needs to take some time before he begins in order to be sure all the rats are the same age, same state of health, and in the same environment (kind of cage, temperature, diet, etc.). Rusty also needs to be sure there are no outside influences on his rats – such as someone feeding them candy. Rusty needs to make sure music is the only variable in his experiment. These things would help him to be sure his assumptions are valid. Of course Rusty can never completely isolate his experiment from outside influences, but giving it his best try would make the study more respectable in the judge’s eyes – not to mention more reliable.

The second assumption Rusty is making is more philosophical and hard to pin down. Rusty has a bias. Rusty has a bias against rock music and for classical music. Before Rusty begins, he theorizes – in his hypothesis – that the rock music will adversely affect the rats, and classical music will help the rats. While creating a hypothesis (what he predicts will be the result of the experiment) is the right thing to do, Rusty should not let his bias against certain kinds of music turn this hypothesis into an assumption. He needs to resist his bias. Unfortunately, Rusty assumes (in the back of his mind where he isn’t aware of it) that the rock music will have bad effects and that the classical music will have good effects – before he even starts. Rusty interprets any changes he sees in light of his assumption – if he sees grey hair, then it’s because of the music, but if he sees growth, it’s because of the music.

Rusty needs to stop and take a more objective look at things. Rusty needs to recognize his assumptions and work to eliminate them as assumptions – it would help to make his study more complete and accurate.

But, I wanted this little story to have a happy ending, so here is the next entry in Rusty’s diary:

“Oct 23: Have made a few changes around here. Replaced Elvis with younger rat “Frankie” and started over. Moved rats upstairs and told sister not to touch. Hope things go better. Excited and wondering about how experiment will turn out.”

Now we’ll skip down to after the science fair:

“Nov 27: Science fair was today. Everything went very well. When I explained to judge how I did the study, taking the precautions I did, the judge was impressed. Says it was “done in a very scientific way.” I explained how music didn’t seem to affect my rats much – except to stimulate hair growth. Didn’t win a prize though – Gus got loose and bit the judge.”

Here are some questions for today:

  1. What are some other assumptions Rusty could be making in this example?
  2. What are some other school subjects where recognizing assumptions is important?
  3. Find a news report or an article that makes an assumption.

First appeared in Homeschooling Today magazine, July-August 2003.

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1 • Patricia Rider • May 04, 2009 • 10:02 PM

This was a great article and very timely for me.  I’m a mother of 4 children and I am guilty of making assumptions based on my biases constantly.
Thank you for reminding me to take a good long hard look at what I’m thinking and why.  My family will thank you also I’m sure!

Sincerely,
Mrs. Rider

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