In mathematical logic, abstract model theory is a generalization of model theory that studies the general properties of extensions of first-order logic and their models.Institution-independent model theory by Răzvan Diaconescu 2008 page 3
Abstract model theory provides an approach that allows us to step back and study a wide range of logics and their relationships.Handbook of mathematical logic by Jon Barwise 1989 page 45 The starting point for the study of abstract models, which resulted in good examples was Lindström's theorem.Jean-Yves Béziau Logica universalis: towards a general theory of logic 2005 pages 20–25
In 1974 Jon Barwise provided an axiomatization of abstract model theory.J. Barwise, 1974 , Annals of Mathematical Logic 7:221–265
See also Lindström's theorem Institution (computer science) Institutional model theory
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