Re: Tabula Rasa


Ross Ridge wrote:
Nikolas Landauer wrote:
Ross Ridge wrote:

That was the level Nikolas was trying explain things at.

No, it's not.

By using the term "peripheral vision" that in fact was the
level you were explaining things at.

You started talking about seeing detail in peripheral vision, which no
definition of peripheral vision I've seen addresses.

I wear glasses, so I am supremely aware of where my
peripheral vision and my normal vision are demarcated.

Your glasses do not demarcate where your peripheral
vision starts. The receptors on the back of your eyeballs
do.

I am aware of that. However, the edges of my glasses are a decent guide
to where *in my field of vision* my peripheral vision starts, and thus
anything I can see to the sides, but blurry, is very likely in my
peripheral vision.

People can see movement (not detail) well outside the field of
*detailed* vision, and that ability is vital to how people perceive
their environments. In addition, they can see gross shapes or
continuations of large physical entities they can also perceive in
their detailed field of vision. A first-person view on a flat 2-D
screen is equivalent to having blinders on either side of one's face.
You can approximate a realistic field of vision by constantly twitching
view to the sides, but that's not the same thing as *having* peripheral
(but blurry) vision.

As a simple, very broad and very approximate experiment, without moving
your head, hold your arms straight out from your sides, with your hands
at about head-height. Keep your eyes on the screen, and slowly move
your arms inward until you see movement at the edges of your field of
vision. Stop moving your arms. Now, without moving your arms, go ahead
and move your head, looking at your arms and approximating the angle
they form. This is your total possible arc of vision. Most of that arc
will be blurry, but you can see movement in those areas.

For me, that arc is about 160 degrees. I would be highly surprised if
that was hugely different for most people, especially given how crappy
my vision is.

Now, move the hands in further until, with your eyes still focused on
the computer screen, you can start to perceive details on your hands
themselves. Again, stop moving your arms, and approximate the angle
they form.

For me, that new arc is about 90 degrees. Again, I would be highly
surprised if that was hugely different for most people, especially
given how crappy my vision is.

A first-person view does wonderfully at the latter, but fails utterly
for the area outside the latter, but inside the former. While a
third-person view gives *too* good a view, it's closer to the former
than the latter, and I've had two decades of experience identifying
with an avatar I was looking down at, or forward at the backside of, so
I find it trivial.

--
Nik

.

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