I had planned to get down to brass tacks as quickly as possible, with an object example from Ashby’s Cybernetics that made an impression on me at an early stage in my thinking about intelligent systems. But while I was looking for that my eye fell on on another passage that so well articulates one of the deepest roots of scientific reasoning that I could not resist reciting it here.
Quantity of Variety
7/1. In Part I we considered the main properties of the machine, usually with the assumption that we had before us the actual thing, about which we would make some definite statement, with reference to what it is doing here and now. To progress in cybernetics, however, we shall have to extend our range of consideration. The fundamental questions in regulation and control can be answered only when we are able to consider the broader set of what it might do, when “might” is given some exact specification.
Throughout Part II, therefore, we shall be considering always a set of possibilities. The study will lead us into the subjects of information and communication, and how they are coded in their passages through mechanism. This study is essential for the thorough understanding of regulation and control. We shall start from the most elementary or basic considerations possible.
7/2. A second reason for considering a set of possibilities is that science is little interested in some fact that is valid only for a single experiment, conducted on a single day; it seeks always for generalisations, statements that shall be true for all of a set of experiments, conducted in a variety of laboratories and on a variety of occasions. Galileo’s discovery of the law of the pendulum would have been of little interest had it been valid only for that pendulum on that afternoon. Its great importance is due precisely to the fact that it is true over a great range of space and time and materials. Science looks for the repetitive.
7/3. This fact, that it is the set that science refers to, is often obscured by a manner of speech. “The chloride ion …”, says the lecturer, when clearly he means his statement to apply to all chloride ions. So we get references to the petrol engine, the growing child, the chronic drunkard, and to other objects in the singular, when the reference is in fact to the set of all such objects.
- Ashby, W.R. (1956), An Introduction to Cybernetics, Chapman and Hall, London, UK. Republished by Methuen and Company, London, UK, 1964. Online.