Although Suppes’ paper will serve us as an example of an alternative view of scientific theories, it isn’t really his intent to provide such an alternative. His aim is characterize the idea of a “model,” something that has an important place in science no matter what view one has of the nature of theories. The sense in which this is an alternative view of theories can be found mainly in what Suppes sees as the importance of this idea; for, if models seem to be more fundamental than theoretical laws, models can supplant those laws as what is central to theoretical science.
• The first section of the paper consists of a series of quotations serving as examples of the use of the term ‘model’ and followed by a commentary on these examples. You should look for the examples that strike you as most worth discussing, but I’ll suggest a few points in Suppes’ commentary that seem to me especially important.
• Notice the distinction made (on p. 289) between a model and a theory as a set of sentences.
• Notice also Suppes’ discussion of the distinction between physical models and abstract “set-theoretical” models, pp. 291-2. (The point of bringing in set-theory is that it provides a means of describing abstract mathematical structures. The “ordered quintuple” on p. 291 is a simple example of the use of its devices—in this case merely to collect the various aspects of a model into a single entity.)
• Finally, notice Suppes’ discussion, on pp. 292-3, of the relative frequency in the use of the term ‘model’ in various sciences.
• The second section looks at three uses of the concept of a model.
• The idea of reducing one theory to another might be stated in terms of their laws, but Suppes suggests seeing it as a relation between classes of models.
• “Gedanken experiments,” or “thought experiments,” explore interrelations of concepts in concrete, but not physically realizable situations. Suppes seems to regard them as essentially arguments concerning models.
• Finally, he looks at the idea of a “model of the data.” Most of the detail of the example he presents (on pp. 297-300) in connection with this idea is not necessary for the basic illustration. The last paragraph of his discussion (beginning on the last line of p. 299) may be enough along with the general discussion of the idea on p. 297.
To compare this with Feigl’s account of theories, look back at the first paragraph of p. 9 of Fiegl’s article. Models in Suppes’ sense can be seen as a more exact formulation of the idea of “analogical models” that Feigl refers to. The mathematical theory of models serves as a way of discussing the meaning of mathematical theories. And, if abstract models can provide meaning to theoretical laws, one gets a source of meaning alternative to the “upward seepage” from empirical applications, something that Feigl hesitates to accept.