When you press the light switch, the light goes on. Neither do you need to know were the cables are passing in the wall, nor where the electricity is coming from. In fact, you don’t need to know that there are cables or that there is electricity. In your mind, there is a connection between the switch and the lamp. How this is implemented is hidden from your view. It is inside a black box. There is a horizon of accessibility.
Inside your body and your mind, there is such a horizon as well. When you press the switch, you don’t know how you are doing it. You may not know anything about muscles and nerves and about mitochondria and the cerebellum and the pyramid cells in your brain. This whole system is at your disposal but you don’t need to know about it and you cannot look into it. You get a limited amount of information about your body posture from some sensors inside your muscles, but that is it. Here as well, there is a horizon of accessibility.
The light from the lamp goes into your eye, stimulates receptors in your retina which in turn stimulate signals in nerve cells. You don’t need to know anything about how these signals are processed to give you a perception of the lamp. What you perceive is a lamp, not single points of brightness or color. You perceive objects but you don’t know how this works. You cannot peer into the workings of your perceptive system. There again is a horizon of accessibitity.
When you look at a work of op-art, a picture that was constructed in such a way that it does not provide a single interpretation but allows for different groupings of its elements without your perception settling into a single one, you will see that there must be a lot of processing and calculation going on under the hood. The picture seems to flicker. It is as if waves from distant places come from beyond the horizon, betraying a distant storm.
The hiding of information here serves as a means to keep complexity low. We just think of a movement, and some automatic program is launched to execute the movement.
As the initial example is showing, this principle of reducing complexity by building a black box or of creating a horizon of accessibility also occurs in technology. You see a program running on your computer, an app on your mobile device, a page in the internet, but you don’t know about how exactly it works, if that server is standing in Britain or Australia or if it is distributed over both places. You cannot tell if the messages from the server to your computer traveled through an undersea cable or through a satellite link. There is a horizon of accessibility and normally you cannot see behind it. In this way, we can do more and more complex things without increasing the complexity of our subjective environment beyond what we can manage.
If you enter a shop to buy a jacket or a coat, there is such a horizon as well. You don’t know where these clothes are coming from, under which conditions they were made. You can’t tell if they were made by people working under slavery-like conditions. These people are behind the horizon. The economic system just like our technological systems employs this principle called “information hiding” in computer science. But here, there are people behind the horizon. The horizon is erected to hide exploitation. The slaves of ancient Rome who were heating the baths and the floors of the villas just lived in the basement of the houses. We are using our transportation and communication technology to separate the producers from the consumers and this makes exploitation possible without us noticing it.
And here might be the self-destructive potential of this principle. We are using up and destroying the resources of our planet, but for some time we manage to hide this destruction behind a horizon. The world of the consumer looks just fine, but behind the horizon, the debris of this civilization is piling up. At some time, there will not just be ripples coming from beyond the horizon. A tsunami will come.
(The picture is from http://en.wikipedia.org/wiki/File:Riley,_Movement_in_Squares.jpg, turned by 90 degrees).
Related articles: https://asifoscope.org/2012/11/20/an-open-letter-to-the-human-brain-project/. Here I have employed the idea of the horizon of accessibility to discuss ethical problems in brain science and the philosophy of consciousness.