社会发展合力论是恩格斯在《致约·布洛赫的一封信》中首次提出的关于社会发展动因的理论。笔者认为,社会发展合力论是有效揭示社会运行规律的重要理论,是我们了解历史、认清现在、把握未来的有力杠杆,遗憾的是,恩格斯对该理论仅是点到为止;因而沿着恩格斯的思路再做深入探讨很有必要。 The concept of social development cooperation is the theory put forward by Engels in his “Letter to Job Bloch” for the first time on the motivation of social development. The author believes that the theory of social development cooperation is an important theory for effectively revealing the law of social operation and is a powerful lever for us to understand history and recognize the present and grasp the future. Unfortunately, Engels lamented that the theory was only to the point; thus, The idea of ​​doing further research is necessary.