An interesting addendum to Rumsfeld's categorization of knowledge is Slavoj Zizek's notion of the unknown known: What he forgot to add was the crucial fourth t

An interesting addendum to Rumsfeld's categorization of knowledge is Slavoj Zizek's notion of the unknown known: What he forgot to add was the crucial fourth term: the "unknown knowns," the things we don't know that we know-which is precisely, the Freudian unconscious, the "knowledge which doesn't know itself," as Lacan used to say. If Rumsfeld thinks that the main dangers in the confrontation with Iraq were the "unknown unknowns," that is, the threats from Saddam whose nature we cannot even suspect, then the Abu Ghraib scandal shows that the main dangers lie in the "unknown knowns" - the disavowed beliefs, suppositions and obscene practices we pretend not to know about, even though they form the background of our public values." http://www.lacan.com/zizekrumsfeld.htm http://www.lacan.com/zizekrumsfeld.htm I agree with Zizek's assessment that unknown knowns are even more dangerous than unknown unknowns.