Sunday, April 10, 2016

ATI Wisdom Booklet 1: Science Portion - How eyes work

Thanks to Homeschoolers Anonymous, 54 of the ATI Wisdom Booklets have been posted online.

In each Wisdom Booklet, there are two science-related sections.  The first section "Science" covers "Chemistry, Biology, Astronomy, Geology, Physics, Mathematics" while the "Health" section covers "Health, Nutrition, Behavior, Counseling".

I've read through the first 15 or so and was surprised how haphazard the information in the booklets are and how poorly designed the lessons are.

I'm just going to jump into the Science section of the first booklet.  The first part is a quick overview of the material in the booklet.

Right off the bat, the lesson starts by teaching an oversimplified lesson.  Yes, newborn babies do have much experience using their eyes, but their vision is as limited by the immaturity of the areas of the brain that manage vision.  Since the booklet wants us to "train our minds to see things others overlook", I'd like to add that I see a picture of a baby who is at least 7 months old and can see much better than a newborn.  At this point, I figured the lesson was on how eye muscles work to give vision; turns out that's NOT the lesson.

That's a nice diagram of the muscles of the eye.  The booklet does absolutely nothing with that diagram.  The four focusing errors will be discussed later on along with two more disorders that didn't make it onto the overview page.  The question in italics at the bottom shows an overarching theme to these booklets: Topics are stretched, mashed and oversimplified for the express purpose of teaching a daft spiritual lesson.

Next comes a series of questions that you are supposed to see if you can answer before the lesson.  Of the nine questions, five are science questions and four are pseudo-theological questions.  Practically, asking "what are spiritual strabismus and astigmatism?" is a poor teaching choice since the term "astigmatism" hasn't been introduced yet.

I included the questions for the "Medicine" section to demonstrate how haphazard the "linked" topics are.  There is no clear connection between focal disorders of the eye and adrenalin production.

These booklets do not teach intensive reading skills.  Each question at the beginning has a section that answers the question explicitly.

The explanation in this paragraph is subpar.
  • First, I don't see the point of introducing the whole "eyes see light, not objects" unless the booklet is going to discuss how the brain learns to make sense of the information collected by the eye. 
  •  Second, the rays don't have to be spread apart per se to be seen.  A beam of light could pass in a straight line from the object through the eye and land on the retina to be seen.  The benefit of focusing is not that light HAS to be bent; it's that the eye gets a far larger field of vision than it would have otherwise.  The eye can also see objects clearly at a variety of distances without the person having to move.
  • Third, light isn't bent four times in the eye.  It's bent twice.  Most of the bending or refraction occurs when the light beam moves from the air through the cornea.  A smaller amount of refraction occurs when the light passes through the lens.  While the lens bends the light less than the cornea, the lens can adjust the amount of bending of light so that the eye can focus.
  • Fourth, focus is relative.  There's an area of tightly packed vision cells called the fovea that light needs to fall on to to get fine detail.  The other portions of the retina, though, also detect light and can be used for shape and color of objects.  That's why you can read the screen of the computer and still see the other pieces of furnature surrounding the computer at the same time.  

A few problems:
  • First, the amount of bending that occurs in the aqueous humor (and the vitreous humor) is tiny compared to the bending that occurs in the cornea and lens.
  • Second, that's a horrible diagram of the light entering the eye.    The optics diagram - the lines of light that go from the drawing of a human to the back of the eye - don't show either what the previous paragraph describes OR what really happens in the eye.  Look at the line from the head of the figure.  The line bends in the cornea which is right, but then continues on in a straight, unbent line until it hits the retina.  According to the Booklet, there should be for separate bends in the light ray before it hits the retina.  Likewise, both of the dotted lines pass through the cornea without bending, then are bent by the lens.  Here's a better image:

  • The image above doesn't show the refraction through the cornea, but it shows how all of the bending of light occurs before the vitreous humor.
  • The final problem is that the image in the Wisdom Booklet has the head of the person falling on the part where the optic nerve enters the eye. That point is called the optic disc and it's the cause of the blind spot in each eye.  In other words, that image would appear to be a headless person.
  • These discussions of nearsightedness and farsightedness are fine.  My only concern is that if this is being presented to young kids they might end up believing that eye disorders are caused by being self-centered or overlooking family members.
  • Normally, this would include a discussion of how corrective lenses could fix the eyes.  Since it wouldn't be that hard to shoehorn "corrective lenses = Jesus", I don't know why it was left out.

  • Well, the strabismus section could be an issue.  Spiritual strabismus is caused by having one eye on God and the other on the world.  Presumably, the eye on the world is the weak eye that needs treatment.  The problem is that the treatment for strabismus is covering the strong eye to let the weak eye get stronger before the child loses vision in the eye.  (This loss of vision is caused by the brain's response to conflicting input from the two eyes.  Eventually, the brain "drops" the weak eye.)
  • The astigmatism section could be better.  It causes blurriness in one or more part of the field of vision.  (On a unrelated note, WTF about spiritual astigmatism?  That's a sad, frantic punt attempt even for an ATI booklet.....). 

  • So....adults get glasses and no one else does?  God, these people need to have a higher income per person ratio.
  • My only problem with the cataracts section is that "corrective lenses" is being used to describe glasses or contacts in presbyopia and an intraocular lens in cataracts.  That could be misleading for people who don't have experience with cataracts.
One post down, 107 more to go.....

Next post: Fight-or-flight meets Jesus while a bear sow eats a stupid human.

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