Read the passage and answer the question : 
Post modernist thinkers hold the view that there cannot be objective knowledge of social issues.

For the Post-Modernist, knowledge is not simply a cognitive factor : knowledge is also normative and political. Power and knowledge are mutually supportive and they directly imply one another. The Post Modernist are critical of classical liberals as well as contemporary positivist who believed in objectivity and superiority of science. Through deconstruction, the post modernist want to look at every accepted or settled idea with now lenses. 
According to Post-Modernist thinker, which attribute of knowledge does not exist?