Tarski's theorem on the concept of truth

Tarski's theorem addresses how we can define the concept of "truth" for a formal language, like logic or mathematics. It states that a sufficiently expressive language cannot contain its own truth definition without leading to contradictions. To avoid this, the truth of statements in such languages must be defined in a way that refers to an external, more comprehensive framework, ensuring the concept is consistent. Essentially, Tarski showed that truth can't be fully contained within the system it describes; instead, it requires a higher-level perspective to properly understand and define truth without paradoxes.