Mencius, also known as Mengzi, was a Chinese philosopher who lived around 372-289 BCE. He is considered one of the most important figures in Confucianism, building on the ideas of Confucius. Mencius emphasized the inherent goodness of human nature and believed that people could cultivate their virtues through education and self-reflection. Mencius argued that a just government should care for its people and promote their well-being. He introduced the concept of the "Mandate of Heaven," suggesting that rulers must govern wisely and justly to maintain their authority. His teachings continue to influence Chinese thought and ethics today.