Knowns and Unknowns

Take a minute to read these lines from Plato’s Apology: it is from Socrates’ defense:

“I am wiser than this man; it is likely that neither of us knows anything worthwhile, but he thinks he knows something when he does not, whereas when I do not know, neither do I think I know; so I am likely to be wiser than he to this small extent, that I do not think I know what I do not know.”

While the sentiment is definitely true, the wording is, well, heavy. Not easy to read.

Now contrast that with how the same sentiment was expressed by Donald Rumsfeld:

“There are known unknowns. That is to say, there are things that we know we don't know. But there are also unknown unknowns. There are things we don't know we don't know.”

Known unknowns. Unknown unknowns. Trust an American to explain an idea in simple (and oh yes, very quotable) terms!

Errol Morris, however, warns us of the dangers of the above approach taken too far:

“Progress hinges on our ability to discriminate knowledge from belief, fact from fantasy, on the basis of evidence. It’s not the known unknown from the known known, or the unknown unknown from the known unknown, that is crucial to progress. It’s what evidence do you have for X, Y or Z? What is the justification for your beliefs?”

Rumsfeld, if you remember, was the US Secretary of Defense under George W. Bush. He never heeded Morris’ warning when he marched into Iraq. As Morris scathingly says:

“Basic questions about evidence for W.M.D. were replaced with equivocations and obfuscations. A hall of mirrors. An infinite regress to nowhere. What do I know I know? What do I know I know I know? What do I know I don’t know I don’t know? Ad infinitum. Absence of evidence could be evidence of absence or evidence of presence. Take your pick. An obscurantist’s dream.”

Morris is obviously right; and yet, Rumsfeld’s known unknowns and unknown unknowns may well be what posterity remembers him for!