Which philosopher established the concept of the 4 cardinal virtues?

The concept of the four cardinal virtues—wisdom, courage, temperance, and justice—was primarily articulated by Plato, particularly in his works such as "The Republic." In this text, Plato discusses the ideal state and the virtues necessary for individuals and society to function harmoniously. He emphasizes that these virtues are fundamental to achieving a balanced and ethical life.

Plato's influence on ethical philosophy was profound, as he built upon ideas from earlier thinkers like Socrates, incorporating them into his own philosophical framework. The cardinal virtues serve as a guide for moral character and decision-making, underscoring the importance of each virtue in fostering a just and well-ordered life.

While Aristotle later expanded and systematized discussions of virtue ethics, the foundational attribution of the cardinal virtues to Plato is widely recognized within philosophical literature. Other figures, such as Confucius, had their own sets of virtues but did not specifically define the four cardinal virtues in the manner that Plato did.