Mencius (Meng Zi in Chinese pinyin) was a Chinese philosopher who was arguably the most famous Confucian after Confucius himself. The most accepted dates of his birth and death are 372 BC to 289 BC and other possible dates are from 385BC to 303/302 BC. Also known by his birth name Meng Ke or Ko, Mencius was born in the State of Zou, now forming the territory of the county-level city of Zoucheng (originally Zouxian), Shandong province, only thirty kilometers (eighteen miles) south of Qufu, Confucius' birthplace. In Chinese history, Confucius was honored as the Sage while Mencius was given the title of ' The Second Sage'.
Mencius concerned himself entirely with political theory and political practice; he spent his life bouncing from one feudal court to another trying to find some ruler who would follow his teachings. He was largely unsuccessful in his endeavor.
He was an itinerant Chinese philosopher and sage, and one of the principal interpreters of Confucianism. Supposedly, he was a pupil of Confucius' grandson, Zisi. Like Confucius, according to legend, he travelled China for forty years to offer advice to rulers for reform. He served as an official during the Warring States Period (403BC - 221BC) in the State of Qi (1046 BC to 221 BC) from 319BC to 312 BC. He expressed his filial devotion when he took an absence of three years from his official duties for Qi to mourn his mother's death. Disappointed at his failure to effect changes in his contemporary world, he retired from public life.
As a Confucian, Mencius based his entire system of thought on the concept of jen: 'humaneness', 'humanity', 'benevolence', etc. To this basic doctrine he added the concept of: 'righteousness', or 'duty'. Mencius believed that the 'humaneness' or 'benevolence' that you show to individuals should in some way be influenced by the type of personal relationship you have to that person. One displayed jen to a person based on that person's position and the obligations you owe to that person, then, means that we have obligations to people that arise from social relations and social organization, not because there is some divine law mandating these obligations.
About Mencius' mother
As Mencius' father died when he was only three years old, he was raised and educated by his mother during his childhood. It was said that his achievements should be mostly attributed to the wise educational mode of his mother. Thus his mother was considered as a successful model of Chinese parents in educating children.
You may have heard of the traditional Chinese four-character idiom: Meng Mu San Qian (mou bo san sen) of which the literal translation is Mencius' mother moved three times. It refers to the legend that Mencius' mother moved their house three times - from beside a cemetery to beside a marketplace (other versions of the story said the move was to a house beside an abattoir), to finally beside a school - before finding a location that she felt was suitable for his upbringing. As an expression, the idiom refers to the importance of a proper environment for the proper upbringing of children.