Zhang Zai (1020-1077 AD) was a native of Hengqu, Meixian (in Shaanxi) during the Northern Song Dynasty. In his youth, Zhang Zai enjoyed studying military strategy. Fan Zhongyan greatly admired his talent and advised him, "Scholars have their own pursuits; why must you discuss military affairs?" Zhang Zai then dedicated himself to academic studies.

Later, Zhang Zai passed the imperial examination and served as a local official in several positions. Because he dared to speak frankly, he offended powerful ministers and resigned at the age of 49, returning home to study.

Hengqu was a remote and impoverished area. Although Zhang Zai owned some land, his income was barely enough to sustain his family, and he had to live frugally. However, he was content and did not dwell on it. Every day, he would plunge into his study, close the door, and spend the entire day diligently reading, often forgetting to eat or rest while pondering problems. Late at night, long after his wife and children had fallen asleep, he would lie in bed still deep in thought. If an idea came to him, he would get up, put on his robe, and happily pick up his brush.

Many young people from near and far came to him for tutelage. For some students from poor families who couldn't afford tuition, he would even subsidize their meals and share their hardships.

In one of his essays, Zhang Zai said, "Poverty, low status, and distressing objective conditions can actually temper one's will and are used to help you achieve success."