There are known knowns. These are things we know that we know. 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. – Donald Rumsfeld

It ain’t what you don’t know that gets you into trouble. It’s what you know for sure that just ain’t so. – Mark Twain

The 2014 documentary by Errol Morris about Donald Rumsfeld, The Unknown Known, has brought the epistemological discussion about what it means to be ‘known’, a discussion usually relegated to the philosophy departments of prestigious academic institutions, out into the open. Many of us watched as Rumsfeld uttered these words back in 2002, but few of us really parsed them carefully and saw the flaw at the center of his statement. The flaw that is so perfectly captured in the quote by Mark Twain.

Looking at these two quotes above reveals what Rumsfeld got wrong (or just missed) that is arguably the most important aspect of what happened in the invasion of Iraq. Mark Twain nailed it. What gets you in trouble is what know for sure that just ain’t so – the unknown knowns. Figure 1 illustrates this simple relationship between knowledge and truth.

 Knowledge - Ignorance

Figure 1 – Knowledge and Ignorance[i]

The issue of what is known and unknown, and what is true and not, confronts innovators every day. For innovators themselves, they must consciously and continuously question their knowledge of the world and, with awareness and practice, they do this naturally. But a large part of an innovator’s job is to understand other people, the customers who will adopt an innovation and the people who influence adoption, including those within their own organizations.  These others also ‘know’ things that are not true but, unlike the innovator, they usually don’t question this untrue knowledge and often act on it..

In the model depicted above, there are three categories of knowledge and ignorance, in the ‘Rumsfeldian’ taxonomy, there are four categories. Something is missing from this model. That something consists of the things we do not know yet but we recognize that we need to find out. This category of knowledge is best represented by the questions we ask ourselves and others. Questions represent our effort to define what we think we need to know – the unknowns. Figure 2 illustrates how adding questions to the model of knowledge and ignorance results in the four categories of interest.

 Known - Unknown

Figure 2 – The taxonomy of known and unknown

In this model, we have questions that have been answered to a comfortable degree of certainty. This is our knowledge, and it can be true (known-known) or not (unknown-known). We also have unanswered questions, those that we know to ask (known-unknown) and those that we do not know to ask (unknown-unknown). Note that the ‘Questions’ category overlaps both what is known and what is unknown. In addition to the questions that arise from thinking about what we don’t know, we should also be asking ‘is what we know true?’.

So what are the practical implications of this model to the innovator? It is clear that the quantity and quality of the questions asked is critical. Questioning and learning are how an innovator explores the two areas of knowledge and truth that can really trip them up – the unknown-unknown and the unknown-known.

In addition, this taxonomy provides the innovator with the means to look at and deal with the knowledge of adopters and influencers of adoption. By being conscious of what these other individuals know and don’t know, what is true and not, and the questions they are asking, a clearer picture of the knowledge landscape can be formed.

This can be especially helpful when navigating the internal barriers within an organization that any new innovation faces, especially innovations that are disruptive to the organization itself. Organizations are full of the unknown-known – knowledge that has built up over the years that everyone ‘knows’ to be true. How often have you heard the following statements or ones like them? These are indicators that there might be a lot of unknown-knowns ‘lurking’ about, ready to derail a disruptive innovation.

  1. We’ve tried this before and it didn’t work.
  2. If it’s so good, why isn’t someone else doing it?
  3. We’ve never done this before so what makes you think we can do this?
  4. It’s just not us. We are not good at …
  5. We’ve always done it this way and we’ve been successful.

This model of knowledge and ignorance makes it possible to recognize the four categories of the known and the unknown and thereby to develop the proper questions to direct exploration and learning. It turns out that what Rumsfeld gave us with his statement back in 2000 may turn out to have value after all.


[i] Ayyub, Bilal, Methods for Expert-Opinion Elicitation of Probabilities and Consequences for Corps Facilities; IWR Report-00-R-10; U.S. Army Corps of Engineers; 2000

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