Abstract:
We define the operations of an inessential combination and an almost inessential combination of models and theories. We establish basedness for an (almost) inessential combination of theories. We also establish that the properties of smallness and $\lambda$-stability are preserved upon passing to (almost) inessential combinations of theories. We define the notions of coloring of a model, colored model, and colored theory, and transfer the assertions about combinations to the case of colorings. We characterize the inessential colorings of a polygonometry.
Keywords:inessential combination of models, inessential combination of theories, colored model, colored theory.