The famous Greek philosopher known for advocating for rational thought is Socrates. Living from approximately 470 to 399 BCE, he is often referred to as one of the founders of Western philosophy. Socrates emphasized the importance of questioning, dialogue, and critical thinking in the pursuit of knowledge and understanding. His method, known as the Socratic method, involved asking probing questions to stimulate critical thinking and illuminate ideas. Although he wrote no texts himself, his ideas were recorded by his students, particularly Plato. Socrates' focus on ethics, virtue, and the examined life continues to influence philosophical discourse today.