Plato's philosophical ideas were shaped by several influences, including his teacher, Socrates, and the socio-political context of ancient Greece. Through dialogues, particularly "The Republic," Plato explored concepts like justice, the nature of reality, and the ideal state. His theory of Forms posited that non-material abstract forms are the most accurate reality, distinguishing between the visible world and a higher realm of true knowledge. Additionally, Plato's reflections on knowledge, ethics, and politics laid the groundwork for Western philosophy, influencing countless philosophers and political theorists throughout history.