KARL JASPERS FORUM

TA 79 (J JOHNSON)

Commentary 45

THE PERCEPTION OF MOTION
by Adhanom Andemicael
2 October 2006, posted 7 October 2006

<1>
When the mind experiences a quale such as "color," it experiences this quale at a single moment of consciousness (i.e., at a single *point* in mental time). We know that the mind senses motion. But how exactly does it sense it ? *When* exactly does it sense it? I suggest that consciousness senses motion at a single moment of awareness (i.e., at a single *point* in mental time).

<2>
A succession of individual "moments of awareness" makes up a "period of consciousness."

<3>
If a moving entity appears to be "motionless" at every moment of awareness, the entity is *always* seen as an "object at rest." The mind never perceives the entity as being an "object in motion." I suggest that there is only one way that consciousness can experience an entity as being an "object in motion." The mind must perceive the entity as being "in motion" at each point in mental time. The entity must appear to be "moving" at each moment of awareness.(1)

***

<4>
Certain kinds of images (i.e., blurred images) suggest motion. Artists sometimes rely on this effect in order to represent flux (i.e., motion) in their paintings.

<5>
Note, however, when viewing this kind of blurred picture, consciousness does not actually perceive motion. Instead, the mind perceives a *static* image that is *suggestive* of motion.

***

Argument:

<6>
1. Consciousness is an instantaneous phenomenon.

2. Conscious experiences are therefore perceived instantaneously.(2)

***

Argument:

<7>
1. The perception of motion is an experience.

2. All experiences are instantaneous.

3. The perception of motion is therefore instantaneous. (Motion is perceived instantaneously.)

***

THE PERCEPTION OF CHANGE

<8>
A perception of motion is a perception of "change." When the mind senses motion, the mind has the impression that an object is changing its location.

<9>
The mind can perceive "changes" in many other properties -- e.g., it can sense changes in color, brightness, temperature, etc.

***

<10>
A duration of mental time is a continuum of instants. If an experience is perceived, it must be perceived *at* these individual instants. If the mind is to perceive "change," the mind has to perceive it *at* an individual instant. (There is nowhere else that "change" *can* be perceived.)

<11>

We might claim that consciousness does not perceive change at an instant. Note however, a duration of mental time, d, is a series of instants. If change is not perceived at a single instant, then change is not perceived at *any* instant, i, in the duration d. If change is not perceived at any instant, i, change is never perceived at any time throughout the duration d: Change is never perceived.

<12>
We can make the assumption above ("consciousness does not perceive change at an instant"). However, if we make this assumption, we are forced to conclude that change is never perceived.

<13>
We know, however, that change *is* perceived. Thus our assumption above ("consciousness does not perceive change at an instant") must be wrong. We must conclude that consciousness does perceive change instantaneously.

***

Argument:

<14>

1. Consciousness is an instantaneous phenomenon.

2. Conscious experiences are therefore perceived instantaneously.

***

Argument:

<15>
1. The perception of "change" is an experience.

2. All experiences are instantaneous.

3. The perception of "change" is therefore instantaneous. ("Change" is perceived instantaneously.)

---------------------------------------------

NOTES

1. An entity may appear to be "moving" at a given moment, m1. Of course, at a later moment, m2, the entity may appear to be "motionless."

2. A single experience is perceived instantaneously. However, this one experience can persist for a small fraction of a second.

A sequence of experiences spans over an extended period of time.

---------------------------------------------

Target Article 61

http://www.kjf.ca/61-TAAND.htm

</exchweb/bin/redir.asp?URL=http://www.kjf.ca/61-TAAND.htm>

http://www.KJF.ca </exchweb/bin/redir.asp?URL=http://www.KJF.ca>

---------------------------------------------

Adhanom Andemicael