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compactness lemma

The Compactness Lemma is a concept in logical mathematics stating that if a set of statements (or formulas) is consistent—meaning no contradictions can be derived—then there exists a complete, consistent way to assign truth values to all statements within it. In simpler terms, if a collection of ideas doesn't lead to a contradiction, we can find a consistent way to interpret or “complete” that collection, ensuring all statements are either true or false without conflicts. This lemma is fundamental in linking local consistency to the existence of a meaningful, comprehensive interpretation.