In the mathematical literature, specifically in model theory, has there ever been a proof that some function, relation, or constant in some structure is definable from the structure, without actually exhibiting a definition, even an abbreviated definition? That is, the proof proves that it is definable, without actually giving a definition, even an abbreviated definition.
2026-04-13 05:13:40.1776057220
A non-constructive proof of definability
89 Views Asked by Bumbble Comm https://math.techqa.club/user/bumbble-comm/detail AtRelated Questions in MODEL-THEORY
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