Skepticism challenges the possibility of certain knowledge, questioning our senses, reasoning, and beliefs. This philosophical approach encourages critical examination of all claims, promoting suspension of judgment in the face of insufficient evidence or conflicting arguments. Key thinkers like Pyrrho, Arcesilaus, and Carneades developed skeptical ideas in ancient Greece. Their methods, including the Ten Modes of Aenesidemus and the Five Modes of Agrippa, aimed to expose the limitations of human understanding and achieve a state of tranquility.