许多研究者担忧，以派别化信息接触为特征，社交媒体难免会带来舆论极化，派 别对立，乃至社会分裂。使用行动者模型模拟人工社会莫尔国，本研究观察了社交 媒体与政治舆论演化的关系。结果显示：（1）社交媒体与舆论极化没有必然联系； （2）社会稳定程度、对主流媒体的干预策略，主流媒体派别观点的极端程度以及信 誉，都可能影响舆论演化的结果；（3）只有在社会失稳和主流媒体信誉流失条件下， 社交媒体对极化有明显推助作用。本文还讨论了莫尔社会舆论分布模式的涌现机制， 模拟研究的启示与局限。

It has been much concerned that social media, characterized by ideology-based selective exposure, would polarize public opinion, intensify partisan con?ict, and divide the society. Using Agent-based Modeling (ABM) to simulate opinion evolution in an artifcial society, Moore State, this study is an attempt to understand the relationship of social media with opinion polarization in the context of political communication. The results show: (1) There is no causal connection between social media and polarization; (2) Social stability, media intervention, and credibility of established mainstream media would all contribute to the outcomes of opinion evolution; (3) Only under the conditions of social instability and damaged credibility of mainstream media, social media could increase the opinion polarization markedly. The emergence of the opinion polarization, the limits of this simulation, and methodological implications of ABM approach are also discussed.