依顧憲成〈東林會約〉所述，東林書院以講學為主旨，並以講論四書為主要內容。顧氏本人說解四書之文獻，包括口頭講學紀錄與文字著作頗多，仍保存至今，不僅是研究東林學派思想的重要依據，也是晚明四書註解的代表性作品之一。顧憲成論學不依循朱子或王陽明既有之格局，其說解四書也以抒發自己心得為主，尤其是針對當時學風的偏失，藉由四書提出改革之道。如闡釋《大學》之「格物致知」，基本上係為了釐清《大學》本義，消除朱子與王陽明兩家的對立。重視《論語》之「學」，以糾正王學末流師心自用的弊病。強調《中庸》、《孟子》之「性善」的觀念，則為去除王陽明無善無惡說所引起之思想及行為的混亂。綜觀顧氏之四書說解，具有補偏救蔽之強烈的時代意義，而其尊重經書與「學」的態度，對明末清初重視經典與知識之學風的轉變尤有啟發作用。

According to the statement in Dung Lin Huei Yue by Gu Shian-Cheng, giving lectures was the main purpose of Dung Lin Academy, and its major content was to discuss and evaluate Four Books. Gu's explanations to Four Books were put in plenty of written works and records of oral lectures. These documents are still well-preserved today. They are not only the important basis for the study of the Dung Lin Sect thoughts, but are also one of the representative works of explanations to Four Books in the late Ming Dynasty.Gu did not follow Chu Tzu or Wang Young-Ming's track. His explanations to Four Books were mainly about expressing his own thoughts. He addressed in Four Books a way of bringing up reformation, especially to the aberration of learning attitudes at that time. For instance, he interpreted Ke Wu Chih Chih (study natural phenomena in order to acquire knowledge) in Da Hsueh (The Great Learning) to basically clear the original idea of Da Hsueh and to eliminate the confronting positions between Chu Tzu and Wang Young-Ming's sects. Also, he valued learning in The Analects of Confucius to correct the malady of regarding oneself as infallible. Finally, he emphasized the concept of the goodness of human nature in The Doctrine of Mean and The Works of Mencius to rid the chaos of thoughts and behaviors by Wang's Doctrine of Human No Good No Evil Nature.To make a comprehensive survey of Gu's interpretation of Four Books, it has an important meaning to the era on improving the social conduct. In addition, the respect to Confucian classics and attitude to learning which showed in his interpretation to Four Books has an inspiring influence on the change of the learning attitude of valuing classics and knowledge between late Ming and early Ching Dynasty.