Encyclopedia of Invisibility

Unknown Unknowns

UNKNOWN UNKNOWNS, epistemological conundrum invoked by then-secretary of defense Donald Rumsfeld during a Pentagon press briefing on February 12, 2002, in answer to a question by NBC’s Jim Miklaszewski regarding the absence of evidence that the Iraqi government was supplying al-Qaeda terrorists with weapons of mass destruction.

After Miklaszewski cited “reports that there is no evidence of a direct link between Baghdad and . . . terrorist organizations,” Rumsfeld responded:

“Reports that say that something hasn’t happened are always interesting to me, because 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. And if one looks throughout the history of our country and other free countries, it is the latter category that tends to be the difficult ones.”

Of the three concepts—known knowns, known unknowns, unknown unknowns—it was the last that resonated, as the public and the media attempted to puzzle out the secretary’s meaning. Arguably the first reference to the concept of unknown unknowns is to be found in the group-dynamics technique known as the Johari window, developed by the psychologists Joseph Luft and Harrington Ingham in 1955. It is an exercise in which someone chooses from a set of adjectives to describe him-
or herself; members of the group then choose adjectives from the same set to describe the person. When the results are collated, the adjectives that neither the person nor the group members chose represent the unknown unknowns, i.e., inaccessible realms of the personality that can nevertheless manifest in unpredictable and potentially dangerous ways.

In his 2011 memoir, Known and Unknown, Rumsfeld credits a fellow member of the 1998 Ballistic Missile Threat Commission (aka the Rumsfeld Commission) with clueing him into the concept of unknown unknowns. The independent commission, perhaps not coincidentally given its namesake, took it upon itself to inflate the likelihood of remote dangers to the United States, in this case a ballistic-missile attack by a rogue state.

In the same book Rumsfeld also glossed his famous quip: “The idea of known and unknown unknowns recognizes that the information those in positions of responsibility in government, as well as in other human endeavors, have at their disposal is almost always incomplete.”

Rumsfeld’s “unknown unknowns” could be thought of as a pseudo-philosophical complement to the infamous “One Percent” doctrine of his ally and former deputy Dick Cheney, vice president at the time of the utterance. According to author Ron Sus- kind, Cheney formulated it thusly: “If there’s a one percent chance that Pa- kistani scientists are helping al-Qaeda build or develop a nuclear weap- on, we have to treat it as a certainty.” The documentarian Errol Morris, whose film about Rumsfeld, The Unknown Known, is based on thirty-three hours of conversation with the former defense secretary, called his tortured reasoning “the epistemology from hell.”

Graham, David A. “Rumsfeld’s Knowns and Unknowns: The Intellectual History of a Quip.” The Atlantic, March 27, 2014. https://www.theatlantic.com/politics/archive/2014/03/rumsfelds-knowns-and-unknowns-the-intellectual-history-of-a-quip/359719/.

Kim, Seong Dae. “Characterizing unknown unknowns.” Paper presented at PMI® Global Congress 2012—North America, Vancouver, British Columbia, Canada. Newtown Square, PA: Project Management Institute.

Newhouse, John. “A Sporty Game I-Betting the Company.” The New Yorker, June 6, 1982. https://www.newyorker.com/magazine/1982/06/14/a-
sporty-game-i-betting-the-company.

Spennemann, Dirk. “The Usefulness of the Johari Window for the Cultural Heritage Planning Process.” Heritage 6, no. 1: 724-741. 2023. https://doi.org/10.3390/heritage6010039.

Zak, Dan. “‘Nothing ever ends’: Sorting through Rumsfield’s knowns and unknowns.” The Washington Post, July 1, 2021.

Image 1: ​​ U.S. Navy photo, Public domain, via Wikimedia Commons

Image 2: Bin im Garten, CC BY-SA 3.0 https://creativecommons.org/licenses/by-sa/3.0, via Wikimedia Commons