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The Function of the
Subreality Machine

In the last chapter we showed that our unconscious mental
activity places our conscious mental activity in an Information-
Limited Subreality. A “subreality machine” exists in each of
our brains, creating everything that we consciously experience.
This is a general description of what is going on. In this chapter
we turn our attention to the question of why the brain operates
in this way. Science understands the human body as a
collection of individual parts, with each part carrying out a
specific function for the benefit of the whole. For us to
understand why the brain contains a subreality machine, we
need to understand the function being performed by this mental
We will look at this issue in two different ways. In the first,
we examine the basic components of the subreality machine, the
information processing upon which it is based. Human color
perception provides the platform for us to conduct this
examination. In our second approach, we investigate the
specific function carried out by the subreality machine in the
human brain. How can the creation of an inner reality facilitate
our finding food, attracting mates, or escaping enemies? Just
what problem did evolution overcome by endowing humans
with a subreality machine? And of all the different information
processing architectures that could have developed in the brain,
why do humans have one that generates a seemingly detailed
and elaborate inner reality? As we will show, the answers to
these questions come from a single starting point: it is difficult
to analyze sensory data.

The Inner Light Theory of Consciousness

Why is the Sun Yellow?
Science has known for over 100 years that light is a wave
of electric and magnetic fields. We are all familiar with waves
moving on the surface of water, where the distance from one
crest to the next might be as small as a few inches, or as large as
hundreds of feet. This distance is called the “wavelength,” and
is the most important parameter associated with a wave. The
wavelength of light is very short, between about 400 and 800
nanometers (billionths of a meter). To scientists, the “color” of
light is exactly the same as the “wavelength.”
Now we want to explore how humans perceive color. The
retina in the eye contains four different types of cells that are
sensitive to incoming light. One of these four, called the rods,
is used only in night vision and cannot distinguish color. This
is why the world looks black and white in dim light. The other
three receptor cells are called the blue, green, and red cones.
Each cone contains a different pigment, causing it to be
sensitive to a different wavelength of light. In particular, blue
cones respond best to light at a wavelength of about 450
nanometers, green cones at about 550 nanometers, and red
cones at about 580 nanometers. Of course, this is very
simplified explanation of a complex topic.
The important point is that light in the physical universe can
have any wavelength between about 400 and 800 nanometers.
However, the eye separates this continuous range into only three
channels. For instance, if we shine a light at 450 nanometers
into a subject's eyes, the blue receptors will be mainly activated,
resulting in action potentials passing along the blue neural
pathway into the brain. Likewise, light at 550 and 580
nanometers causes the same events in the green and red nerve
pathways, respectively. When a mixture of wavelengths enter
the eye, as is the normal case, these three channels activate in
varying amounts.
In short, the only thing that the human brain knows about
color is what can be contained in these three channels. If neural
signals are present on the blue channel, the subject will
Chapter 8: The Function of the Subreality Machine 117

experience the color blue. Likewise, if the green or red channel
is activated, the subject will report seeing green or red,
respectively. Since blue, green, and red are the only “pure”
colors that the human visual system can detect, we call these the
physiological primary colors. All other colors that humans can
experience are nothing more than a mixture of these three.
A good demonstration of this is provided by color
televisions and computer monitors. If you look closely at the
screen with a magnifying glass, you will see that the display is
composed of a large number of small dots, each being either
red, green or blue. By varying the relative intensity of these
three basic colors, it is possible to generate all possible colors
that the human visual system can perceive. However, it cannot
generate all the possible combinations of wavelengths that exist
in the physical universe.
Now we come to the interesting part, what the brain does
with the color information that it receives. Suppose we conduct
an experiment by displaying three different colored circles on
a computer monitor. To start, we will make the three circles the
primary colors, one red, one green, and one blue. We then tell
a test subject the name of a color, and ask him to point to it on
the display. Of course, he has no trouble doing this; any person
with normal vision can easily recognize red, green, and blue.
But now we change the colors being displayed so that each
is a combination of two primary colors. That is, one circle is
blue and green, one is blue and red, and one is red and green.
This is illustrated in Fig. 8-1. We then ask our subject to point
to "blue-green." After looking for a few seconds, he points to
the circle where the blue and green channels are simultaneously
illuminated. When told that scientists call this color cyan, he
shrugs his shoulders and says that blue-green is more
descriptive. We find a similar result when we ask him to show
us “blue-red,” a color also called magenta. Without difficulty,
he points to the correct circle.
But now we find something very strange. When we ask the
subject to indicate red-green he hesitates. After a few moments
The Inner Light Theory of Consciousness

of thought he tells us that there is no such thing as “red-green”;
it is something that he is totally unfamiliar with. When we show
him the circle with the red and green channels illuminated, he
protests that the color is yellow, and there is not the slightest
thing about it that he perceives as red-green. He explains that
red and green remind him of apples on a tree or Christmas
decorations. "That's what red and green are," he insists. "The
color you are pointing to makes me think of the sun and
This phenomenon is well known in science and medicine.
While there are only three physiological primary colors (red,
green and blue), there are four psychological primary colors
(red, green, blue, and yellow). In other words, our brains
transform a mixture of red and green into something that is not
a mixture of anything. Yellow is perceived as a pure color, not
a composite. Yellow is as different from red, green and blue, as
red, green, and blue are different from each other.
To appreciate just how strong this effect is, consider the
colors used in traffic lights. There are three conditions that
must be indicated, stop, go, and caution. The colors we choose
to represent these three conditions should be as different as
possible, making it easy for drivers to distinguish between them.
Given this, an obvious choice might be to use the three primary
colors, red, green and blue. We can also identify an infinite
number of bad choices. For instance, using forest green, lime
green, and pea green would be a disaster, since they are so
But now let's look at the colors that are universally accepted
for this purpose, red for stop and green for go. So far so good;
these two colors are as different as possible. But the color used
for caution is yellow, which is a mixture of red and green
entering the eye. If we consider physiology alone, this is the
absolutely worst choice that could have been made. The
caution light should catch our attention; it should alert us that
the situation is different than it was before. But the sequence of
colors: green to green/red to red, would seem to do the opposite
Chapter 8: The Function of the Subreality Machine 119

Color perception experiment. Humans view the combination of
blue and green as a combination of blue and green. Likewise, a
combination of blue and red is seen as a combination of blue and
red. However, a combination of red and green is seen as yellow,
a primary color that cannot be separated into components.

of this, minimizing the abruptness of the transitions. But, of
course, it doesn't. Humans do not perceive the combination of
red and green to be a combination of red and green. Rather,
they perceive the combination of red and green to be yellow, a
primary color in itself, something that has no relation to either
red or green.
For engineers and computer scientists this is all quite
uninteresting, because its explanation is so simple. As an
example, suppose we asked an engineering team to create an
electronic device that mimics this phenomenon. We might start
The Inner Light Theory of Consciousness

with a color video camera that produces signals for red, green
and blue, just as the human eye. However, the video recorder
we want to use might be designed to store color from four
channels, red, green, blue and yellow. The question is, how
does the engineering team go about changing the data
represented in three channels into data represented in four
The answer is that they build a converter, a device that has
three channels entering, and four channels exiting. The blue
channel simply passes through without being altered. The other
output channels (red, green, and yellow) are calculated from the
other input channels (red, and green) by simple arithmetic
operations, such as addition, subtraction, and comparison.
Figure 8-2 shows a computer algorithm for this conversion, if
you are familiar with such things. The important point is that
this converter could be implemented by analog or digital
electronics, computer software, a biological neural network, or
any similar information processing technology. Constructing
this kind of converter is extremely simple, almost trivial, to an
electronic designer or computer programmer.
Now suppose we ask a scientist to examine the video
recording without providing him the background on how it was
made. After due inspection, the scientist proclaims that it
represents a world containing four primary colors, red, green,
blue and yellow. By this he means that each of these four colors
is irreducible, and that none of these colors can be created by
combining the other three. In other words, the knowledge that
yellow was created from red and green is not contained within
the recording. Based on the recorded video alone, yellow is as
separate and distinct from red and green, as blue is from red and
Of course, this is exactly the situation occurring in the
human visual system. Humans perceive red, green and blue as
Elements-of-reality. That is, they are irreducible, they cannot
be broken into more basic entities. In comparison, the colors of
cyan and magenta are Information, since we perceive that they
Chapter 8: The Function of the Subreality Machine 121

Color converter. This algorithm shows how three primary
colors (blue, green, and red), can be converted into four
primary colors (BLUE, GREEN, RED, and YELLOW).

are composed of blue and green, and blue and red, respectively.
This is just another way of saying that red, green and blue are
primary colors, while cyan and magenta are not. And none of
this is surprising, given that the eye inherently detects three and
only three channels of color, red, green and blue.
But what about yellow? As the color signals move between
the eyes and the brain, yellow is nothing more than a mixture of
red and green. This means that it is Information, exactly the
same as cyan and magenta. However, when yellow is perceived
by our conscious mind, it is irreducible; it is an Element-of-
reality of our introspective world. But as we know, nothing
more than elementary operations are required to make this
change, the kind of operations that are fundamental to all
information processing systems. This lesson here is momentous;
the most basic operations used in information processing have
the ability to change Information into Elements-of-reality.
A critical point to understand is that changing Information
into an Element-of-reality does not require that something be
added, it requires that something be taken away. It is
accomplished by presenting a thing, but at the same time hiding
The Inner Light Theory of Consciousness

how the thing can be reduced to more fundamental components.
Humans look at the color yellow and proclaim that it is
irreducible, a thing in itself, an Element-of-reality. But this is a
handicap, not a capability. It is a fundamental limitation on
understand the thing in question. If we could look at the color
yellow and perceive that it was red-green, we would be more
informed, not less.
In Chapter 6 we showed that the Information-Limited
Subreality has this same property, allowing the inner observer
to see Elements-of-reality, while the outer observer sees only
Information. We called this property the "Principle of relative
reduction." This is information manipulation on a large scale,
sufficient to manufacture an entire reality for a human or other
observer. In contrast, our example of the color yellow is on a
small scale, using the most basic information processing
operations. In more poetic words, we have now examined the
building and also looked at the individual bricks.

The Sensory Analysis Problem
Now we want to examine why the brain contains a
subreality machine. As discussed in Chapter 3, the function of

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