In my previous post, I divided sciences into three categories. Remember that ‘science’ refers to systematic knowledge of a particular subject. The three categories are divided by the purpose of having that knowledge of the particular subject. These categories are theoretical, active and productive. The point of the theoretical sciences is knowledge; of active sciences, action and of productive sciences, an object. Productive sciences are potentially infinite in number and arbitrary in classification and nature.
There are a potentially infinite number of productive sciences. The science of pottery-making (making small objects from clay) is very old. When it became possible to produce electronic objects, the science of electronic production was born. As our knowledge of the world increases, the number of productive sciences increases as well. Nor is this the only factor. If demand increases for a particular kind of object, making it may become a kind of science. All that is needed is for systematic knowledge of how to make it to become economically viable. Our knowledge of the world is always increasing. Since this new knowledge allows for the existence of new things, there are a potentially infinite number of productive sciences.
There is no common way to define the productive sciences. Some sciences are defined by the materials they use to produce their final product. Pottery-making always uses clay. Metallurgy uses metal. But both sciences produces some of the same products. Other sciences are defined by the method they use to produce their product. Construction work is defined by the act of building infrastructure. Still other sciences are defined by the product they produce. So drug manufacturing is the science of making drugs.
There is also no eternal classification of the productive sciences. What I mean by this is that present classification and ordering of the productive sciences is entirely arbitrary. If the past individuals responsible for the present classification had decided differently, we would have a different classification today. Not only that, but because the sciences deals with artifacts, there would of necessity be no right way to classify them. Artifacts are what they are simply because of the plan we have in our minds. There is nothing about the artifact itself that requires that it be the kind of artifact that we call it. So if we changed the plan in our minds, then the artifact would be different. Similarly, if we decided to make artifacts in a different way, then this may be a change in our science or a new science. Which one it is may simply depend on the circumstances.
All of this does not mean that the process of classification and change in the nature of the productive sciences is completely arbitrary. Social structures, individual circumstances, current knowledge and future expectations all limit the ways and directions that productive sciences can grow.