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Logic, the study of reasoning and argumentation, was profoundly impacted by Alfred Tarski's contributions in the 20th century. Tarski's groundbreaking work provided a rigorous foundation for logical concepts such as truth, satisfaction, and definability, revolutionizing the field. His seminal work, "The Concept of Truth in Formalized Languages," established a precise definition of truth within formal systems, influencing not only logic but also philosophy, mathematics, and computer science.