# Destruction of Information/The Performance Paradox:

Ross Ashby was one of the pioneers of Cybernetics. His 1956 book, An Introduction to Cybernetics, is still one of the best introductions to Cybernetics. As I was researching his journals, I came across an interesting phrase – “destruction of information.” Ashby noted:

I am not sure whether I have stated before my thesis – that the business of living things is the destruction of information.

Ashby gave several examples to explain what he meant by this. For example:

Consider a thermostat controlling a room’s temperature. If it is working well, we can get no idea, from the temperature of the room whether it is hot or cold outside. The thermostat’s job is to stop this information from reaching the occupant.

He also gave the example of an antiaircraft gun and its predictor. Suppose we observe only the error made by each shell in succession. If the predictor is perfect, we shall get the sequence of 0,0,0,0 etc. By examining this sequence, we can get no information of about how the aircraft maneuvered. Contrast this with the record of a poor predictor: 2, 1, 2, 3… -3, 0, 3 etc. By examining, this we can get quite a good idea of how the pilot maneuvered. In general, the better the predictor, the less the maneuvers show in the errors. The predictor’s job is to destroy this information.

As an observer, we learn about a living system or a phenomenon by the variety it displays. Here, variety can be loosely expressed as the number of distinct states a system has. Interestingly, the number of states or the variety is dependent upon the system demonstrating it, as well as the observer’s ability to distinguish the different states. If the observer is not able to make the needed number of distinctions, then less information is generated. On the other hand, if the system of interest is able to hide its different states, it minimizes the amount of information available for the observer. In this post, we are interested in the latter category. Ashby talks about an interesting example to further this idea:

An insect whose coloration makes it invisible will not show, by its survival or disappearance whether a predator has or has not seen it. An imperfectly colored one will reveal this fact by whether it has survived or not.

Another example, Ashby gives is that of an expert boxer:

An expert boxer, when he comes home, will show no signs of whether he had a fight in the street or not. An imperfect boxer will carry the information.

Ashby’s idea can be further looked at from an adaptation standpoint. When you adapt very well to your everchanging surroundings, you are destroying information or you are not demonstrating any information. Ashby also noted that adaptation means “destroying information.” In this manner, you know that you are adapting well, when you don’t break a sweat. A master swordsman moves effortlessly while defeating an opponent. A good runner is not out of breath after a quick sprint.

My take on this idea from Ashby is to express it as a form of performance paradox – When something works really well, you will not notice it, or worse you will think that it’s wasteful. The most effective and highly efficient components stay the quietest. The best spy is the one you have not ever heard of. When you try to monitor a highly performing component, you may rarely get evidence of its performance. It is almost as if it is wasteful. Another way to view this is – the imperfect components lend themselves to be monitored, while the perfect components do not. The danger in not understanding regulation from a cybernetics standpoint is to completely misread the interactions, and assume that the perfect component has no value.

I encourage the reader to read further upon these ideas here:

Edit (12/1/2020): Adding more clarity on “destruction of information”.

The phrase “destruction of information” was used by Ashby from a Shannon entropy sense. He is indicating that the agent is purposefully reducing the information entropy that would had been otherwise available. Another example is that of a good poker player, who is difficult to read.

Please maintain social distance and wear masks. Stay safe and Always keep on learning…

In case you missed it, my last post was Locard’s Exchange Principle at the Gemba: