I believe there is a gaping hole in the field of epistemology, particularly in how it categorizes knowledge. We all know philosophers are liars by nature, so why not take from the philosopher in american history, Daniel Rumsfeld.
To quote him directly, "As we know, there are known knowns; there are things we know we know. We also know there are known unknowns; that is to say we know there are some things we do not know. But there are also unknown unknowns—the ones we don't know we don't know."
Slavoj Žižek himself has spoken on the fourth category here, the unknown known.
"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."
In today's world where all facts are up for debate, where unknown unknowns are the greatest threats of all (not known knowns such as human-caused climate change), our best chance for survival is to adopt this framework.
What do you think?
We need to add a third axis
Known known knowns - The known category of facts that are established to be known
Known known unknowns - The known category of possibilities established to be unknown
Known unknown unknowns - The known category of possibilities not yet established or theorized
Known unknown knowns - the known category of unspoken beliefs, practices, and behaviors which are declared to not exist officially.
Unknown known knowns - The category of known facts that is not known to be a category
Unknown known unknowns - The category of possibilities that could be categorized as unknown but is not yet known as a category
Unknown unknown knowns - Ideology
Unknown unknown unknowns - beanis
You had me at beanis