Why did Alfred Tarski’s work on truth become important to logical semantics?

Alfred Tarski’s work became foundational to logical semantics because it provided a rigorous, systematic method for defining truth within formal and mathematical languages, effectively addressing the challenges posed by self-referential paradoxes like the liar paradox.1

Tarski’s approach was significant for several reasons:

• Truth Conditions: He demonstrated how to construct a definition of truth by assigning truth conditions to every sentence in a formal language. This was achieved through "T-sentences," which specify that a sentence is true if and only if a certain condition is met, using a metalanguage to describe the object language without using semantic terms like "true" within the object language itself.1
• Satisfaction: Tarski defined truth in terms of a relation of "satisfaction" between sentence constituents and sequences of objects, allowing truth to be determined systematically.2
• Philosophical Influence: His work transformed how philosophers approached the concept of truth. By shifting the focus from the abstract question "What is truth?" to the more tractable "What does the truth of S amount to?", he provided a framework that later allowed Donald Davidson to propose that a theory of truth could serve as a theory of meaning.12

Ultimately, Tarski’s methods became a cornerstone of model theory, providing the conceptual tools necessary for the development of modern logical semantics.3