"Defending Marx"was the original intention of Althusser's theory.Based on the study of Das Kapital,Althusser's thought focused on the issue of ideology and adopted the method of symptomatic reading to defend Marx theoretically.Althusser upheld the"scientific logic"inherent in Marx's conception of social history.Althusser's efforts to break through the boundaries of ideology revealed the concealment,closure,and hegemony of ideology,which provided a theoretical premise for passing through ideological illusions.Althusser's exploration on the problem of"individual disappearance"in the ideological dimension is a deep extension of Marx's modernity problem of"individual ruled by abstraction",but the"problematic"of ideological psychoanalysis made Althusser miss Marx's"liberation logic"fundamentally.The success or failure of Althusser's"defending Marx"inspires us to deal with the dialectical relationship between metaphysical criticism and post-metaphysical hope properly,and promote the contemporary construction of Marxist economic philosophy,political philosophy and cultural philosophy actively.