Application 3: From the iron to the space shuttle
Apparently an iron is too simple to require a design based on a symbolic model. False.
Let's take a simple technological detail: the holes used for steam exhausts for moisturising the tissue. Some questions are, e.g. how many holes it needs, where, what shape and dimensions are needed for uniform moisturising of the tissue with minimum water consumption and at lowest costs. Clearly, it is possible to build analogic models, which can be tested experimentally. Based on the analogic (image) models one can obtain certain results, but there is no guarantee that the optimal solution was found. The existing image model cannot be modified, as such. If we want to make any change in the image model we have to rebuild it from scratch, as we already know, which implies time and money.
The vaporisation and dispersion process of the steam through a complex structure as the surface of the iron, tissue and the support, is very complex. Physicists, based on symbolic models, with help of computers, solve this type of problem. The rebuilding of the model in order to find a better solution is far simpler on a symbolic model, than on an image model.
If in the case of an iron, the highest risk is that the customers won't buy the non-performing iron, in other cases the risks involved are unacceptable.
For instance, the space shuttle was 'verified' for reentering the atmosphere on a symbolic model. This phase of the flight, by far the most dangerous, would have been impossible to test before the actual flight. The crew was trained on symbolic models in all the phases of the flight, and in all normal and exceptional situations. The astronauts have learned to fly for reentering the atmosphere, based mainly on training on symbolic models.
Given a model (image or symbolic), it can be used to predict its further evolution. This is achieved by changing/ adding/ removing a parameter/ element/ relationship and following what happens. This process is called simulation on the model. As we know, the results of the simulation on the model are called truths associated to the model.
When a model is associated to external reality, by simulating on the model, we can predict the evolution of the external reality. These operations are done either by the human (image and symbolic) or the animal brains (image models only).
We need to note here- it is as important, as it looks trivial: We extend to the external reality the structure of symbolic and image models from our brain. This extension is done not only in the domain of science and technology, but also in all domains of life. For each of us, the world itself is given as a sum of all the projections to external reality of all the active models of the brain. This statement is true for animals as well.
Example: The laws voted in the parliament are long-range symbolic models; they are an extension of the structure of models from the brains of the authors of the laws.