本研究运用远距离人格测量的方法，以动机、政治信念，认知复杂性和同一性这些心理变量解释孙中山政治行为的摇摆主题。通过对孙中山传记材料分析，提取出他典型的政治行为风格，称之为摇摆主题。通过对孙中山及比较样本就职演说的内容分析，得到他的成就、亲和及权力动机水平，并理解孙中山政治行为倾向。通过对孙中山与军阀合作或攻击阶段的演说、访谈和通电文本的内容分析，研究孙中山政治信念和认知复杂性的变化，解释孙中山的政治决策过程和认知结构的变动，以及与实际政治行为的关系。对孙中山的同一性主题和变体进行质化分析，理解孙中山政治行为稳定风格内在的心理机制。研究有以下结果：一、孙中山表现出高成就动机，低亲和动机，中等偏高权力动机。随着从政经验增加，孙中山动机从早期的成就动机占支配，到后期逐渐权力动机占支配。二、在合作和冲突不同阶段，孙中山表现出对立的政治信念类型。在合作阶段，更加友好与合作；在攻击阶段，变得敌意和攻击性。在政治信念的主观博弈中，冲突阶段，存在协作均衡，双方能够通过相互调整行为达到这一均衡；冲突阶段，只能形成僵持的均衡。三、在和平解决的冲突事件中，孙中山表现出较高水平的认知复杂性；在升级为武装对抗的冲突事件中，孙中山的认识复杂性较低。在孙中山主动发起的冲突事件中，冲突前后保持稳定而相对较高的认知复杂性；在孙中山被动接受的冲突事件中，冲突前后认知复杂性显著下降。四、孙中山存在“试图通过所依靠的对立面而消灭它”的同一性主题。该同一性主题在童年和青少年期出现，并在第一次政治尝试中稳定下来。之后的革命行动，均可视为这一同一性主题的不同变体。五、孙中山政治行为的“摇摆”，源于其同一性的矛盾性，并通过动机激活、信念转换和认知复杂性变化完成心理准备，在权力应激情况下启动摇摆。同一性、动机、信念和认知复杂性构成一个完整的“人格格式塔”，成为不同时间和情境政治行为摇摆过程中的心理推动力。

The purpose of this study was interpreting the Pendulousness Theme of political behavior of Sun Yat-sen with psychological variables motive, political beliefs, cognitive complexity and identity, through method of personality assessment at a distance. The Pendulousness Theme, typical style of political behavior of Sun, was extracted by analysis of his biographical materials. Achievement motive, affiliation motive and power motive, got by content analysis of inaugural addresses of Sun and compare sample, were used to understand of political behavior tendency of Sun. The relationship of political behavior, decision-making process, political beliefs and cognitive complexity was interpreted through content analysis of interviews, speeches and open telegram in stages of cooperation or attack with the warlords. The psychological mechanism of stable political behavior style of Sun was interpreted by his identity. There were the following results of the study: First, Sun showed high achievement motive, low affiliation motive, and medium to high power motive. With the increase of political experience, Sun's achievement motive declines and power motive improves. Second, Sun showed opposite type of political belief in cooperation and attack stages. Sun was more cooperation in the cooperation stages, and more hostile and denunciative in attack stages. There was settle equilibrium in cooperation stages of subjective games, and deadlock equilibrium in attack stages.Third, Sun showed higher levels of cognitive complexity in conflict result in peaceful resolution， and lower levels of cognitive complexity in conflict escalated into armed confrontation。The cognitive complexity of Sun was stable and higher in conflict initiated by him, and declined in in conflict initiated by warlords.Fourth, the identity theme of Sun was “trying to eliminate the opposite by relying on its force”. The identity theme appeared in childhood and adolescence, and stabilized in the first political activity. His revolutionary action could be seen as different variants of the theme. Fifth, the contradictions of identity resulted in the Pendulousness of political behavior of Sun. The Pendulousness was started in front of power stress with interaction of motives, beliefs, cognitive complexity. There was a personality gestalt component of identity, motives, beliefs and cognitive complexity, influencing change process of political behaviors.