How did Mencius help spread Confucian ideas?

Mencius, often called the "second sage" of Confucianism, played a pivotal role in spreading and developing Confucian ideas by acting as a social critic, moral philosopher, and political activist.12

He helped propagate the tradition through several key methods:

• Teaching and Mentorship: After traveling to offer counsel to various princes, Mencius returned to his native state of Zou to dedicate his later years to instructing pupils, ensuring the continuity of Confucian orthodoxy.1
• Political Advocacy: He served as a teacher of kings, traveling widely to exhort feudal lords to adopt "humane government" (renzheng) and the "kingly way" (wangdao). He challenged rulers to look beyond narrow self-interest and prioritize the welfare of the common people.12
• Intellectual Discourse: Mencius articulated Confucian moral idealism by debating and exposing the impracticality of competing ideologies, such as the collectivism of Mozi and the individualism of Yang Zhu.2
• Literary Record: His teachings, sayings, and debates were compiled by his disciples into the book Mencius, which remains a foundational text for understanding his amplification of Confucian thought, particularly his doctrine on the inherent goodness of human nature.13