The spread of “capitalism” from West to East not only brought knowledge of an economic model but also offered nations a new path for development. This expansion was met by the rise of the socialist revolutionary movement, which aimed to overthrow the capitalist political and economic system. This article examines the concept of “capitalism” in the context of the debate on socialism. By studying the elaborations of Ziben zhuyi (capitalism) by its proponents and opponents, as well as the debate-related expressions proposed by later scholars in different contexts, this study reflects on the politicization of “capitalism”, the complexity of its meaning, and the degree of political ideology in its implementation. Based on the analysis of relevant papers on the debate, it concludes that (1) as a highly politicized concept, “capitalism” reflects intellectuals’ assumptions regarding China’s future and the evolution of its political ideologies; (2) “capitalism” has a complicated conceptual connotation, and it is necessary to consider its many aspects to present the full picture of what people think about it; and (3) the degree of capitalist ideology varies in different periods and contexts.