Ways To Perfect Vision

How do we perfect our vision?

This can be done through 3 principal parts:

1. The objects

Some objects are close or accessible. Others are distant and inaccessible.

Some are illuminated, others less.

We can approach or move away from accessible objects and increase or decrease the light that illuminates them.

But we cannot do this for remote objects.

2. The internal organs which receive the actions of these objects

We cannot add anything by art to the structure of the nerves and the brain because we cannot make a new body.

3. The external ones which dispose these actions to be received as they should.

The external organs for sight include:

• all the transparent parts of the eye
• all the other bodies that can be placed between it and the object.

All the things of note with these external organs can be reduced to 4 points.

1. All the rays which go to each of the ends of the optic nerve do not come from only 1 part of the object.

They do not undergo any change in the space between the two.

Without this, the images they form could not be either very similar to their original or very distinct.

2. These images are very large in the extent of their lines or their features

They will be all the easier to discern the larger they are.

3. The rays that form them are strong enough to move the small fibers of the optic nerve

This makes them felt, but not so strong as to injure the sight.

4. There are as many objects as possible whose images are formed in the eye at the same time

As many as possible can be seen at a single glance.

Nature has filled the eye with very transparent colorless liquors. These cause the external light to pass to the bottom unchanged.

The surfaces of these liquors cause refractions between the rays according to the qualities of the incoming light.

These refractions divert the light gather to the same point against the nerve.

To solve the defects in the incoming light, Nature has:

• allowed the pupil to shrink almost as much as the strength of the light permits.
• dyed all the parts of the eye opposite the nerve with a black color to prevented any other ray from going towards these same points
• allowed the changing of the shape of the eye’s body so that the light from near and distant objects can still assemble at the back of the eye

But Nature has not given us the means of curving so much the surfaces of our eyes that we can distinctly see objects that are very close to them.

Nature has made the eye’s shape to:

• only look at distant things, as in the case of old people
  • They become flatter and wider as one grows older
• only look at near things, as in the case of young people.
  • The eyes form longer and narrower than they should be