Tarski's theorem

Tarski's theorem, particularly in the context of truth, focuses on the concept of formal languages and their interpretations. Essentially, it states that for any sufficiently complex language, you cannot consistently define the truth of statements within that language using the language itself. This means that some sentences can't be adequately expressed as true or false without stepping outside the language’s limitations. Tarski demonstrated that to truly capture the essence of truth, you often need to refer to an external framework or meta-language, highlighting the complexities of defining what truth actually is in formal logic and mathematics.