Information systems

by Neil Rickert

As suggested in the previous post, I think of a cognitive system as an information system.  In this post, I want to look at a particular information system, namely a video camera.

Let me be very clear here.  I do not think that a cognitive system is very much like a video camera.  Rather, I see them as very different.  However, by looking at a video camera, we can examine some basic principles that seem to be common to all information systems, including human cognitive systems.

In particular, we want to look at:

  • the input phase, where data is gathered;
  • the organization phase, where the data is assembled together;
  • the output stream — the final output information.

The input phase

For the video camera, the data is gathered into a pixel map.  I am going to describe this as categorization.  That might seem a strange term to use for generating a pixel map, so I should first explain why I am using that term.

Let’s suppose that we are using the video camera to picture some place in the world.  To generate a pixel map, in effect we divide up that place into small squares.  This dividing up, sometimes called “carving up the world,” is one of the things that is sometimes referred to as categorization.  And once we have carved up the pictured place into small squares, we gather data about all of the parts of a particular square and bunch them together as pixel data.  In this case, the data would be the intensity of reflected light.  Combining together related things, and treating them as if they were all one thing, is also often called categorization.

So we are carving up part of the world, and combining data.  Both are typical aspects of categorization.  In this case, the categories are the pixel data for the particular pixels.

Forming a pixel map is one particular way of categorizing.  Other information systems may use other methods.  But there always seems to be some categorization as part of the input phase.

How we categorize can also be important.  We usually categorize in a somewhat methodical manner.  I will at times describe this methodical manner as following categorization rules, or as following categorization practices, or as following empirical conventions.  The actual rules or practices or conventions that we follow are typically a pragmatic invention.  They might result from trial and error experimenting to find what practices turn out to be particularly useful.  I’m tentatively planning to have a future post on categorization methods.

The organization phase

The video camera has collected units of data, a unit for each pixel.  But if those are just bundled together willy nilly, they would not be of much use.  So some sort of order needs to be imposed on them.  In the technical sphere, this is typically called a protocol.  The units of data are assembled in some kind of controlled order.  And additional marker units might be inserted to label or identify the particular data units.  We can describe those markers as protocol marks.

At least in the technical world, the protocol is typically a system of rules.

The output stream

The resulting output is a stream (or sequence) of symbols or units.  Some of those units are data units (in our case, they are pixel data).  And some of those units are what I have called “protocol marks.”  That the output stream was assembled in an organized manner, results in there being visible organizational patterns in the stream.  These patterns, collectively, are often referred to as a grammar.  With ordinary speech, the output stream is in the form of natural language statements.  And we see natural language as having such a grammar.

For our video camera output, the grammatical structure allows a receiver of the output stream to separate the data for the different pixels.  This determines which pixel a unit of data is about.  And then knowledge of the categorization rules allows the receiver to determine which part of the external world that data is about.  We might say that the protocol rules or grammar rules, together with the categorization rules, account for the intentionality (or aboutness) of the content of the data stream.

Summary

I have presented some general principles of information systems.  We will see their importance in future posts.  I’ve indicated why a natural language has an apparent grammar.  But, most importantly, I have emphasized the role of categorization.

I have recently been reading Thomas Nagel’s “The View From Nowhere”.  On page 14 (Kindle edition), he writes:

The first step is to see that our perceptions are caused by the action of things on us, through their effects on our bodies, which are themselves parts of the physical world.

So Nagel seems to see perception as something that happens to us.  This appears to be a widely held viewpoint, usually described as “perception is passive”.  But that cannot be right.  We are actively engaged in categorizing the world as part of how we perceive.  Perception cannot be as passive as it is often taken to be.