You make decisions out of a very small slice of what there is to know, and the size of that slice has almost nothing to do with how confident you feel while you decide.
The knowledge pie sorts everything into four parts: what you know, what you know you do not know, what you do not know you do not know, and the awkward fourth slice — the things you are certain of that are no longer true. Businesses are rarely damaged by the first two. The known-and-unknown framing was made famous by Donald Rumsfeld in 2002, though the underlying idea sits in decision-making long before that; the version used here adds that fourth slice, because in an owner-managed business it does more damage than the others.
The four slices
What you know
Your costs, your capacity, your lead times, the things you can go and check. This slice is real, and in a long-established business it is large and reliable. It is also the slice that produces the confidence that leaks into the others.
What you know you do not know
Your honest list of gaps. This is a healthy list, because a question you have named can be answered by lunchtime. It looks like the risk register, so it gets mistaken for the whole of your ignorance.
What you do not know you do not know
Everything you have not thought to ask about. You cannot make this slice smaller by thinking harder, because thinking harder only works on questions you already have. It shrinks through contact: with people who have done the thing, with customers who tell you the truth, with a market you have operated in.
What you are sure of that is not true
This is the expensive one. It is what you learned when it was true and never revisited. It feels identical to knowledge, because it was knowledge — several years ago.
Why does it matter to an owner?
Because nothing in your week challenges that fourth slice. Nobody who works for you is going to sit you down and explain that your view of your own market is out of date. Your team will assume you know something they do not. Your customers will not tell you unless you ask, and the ones who disagreed most strongly have already left.
Experience makes it worse before it makes it better. Twenty years in a trade builds a huge, reliable first slice, and it also builds confidence that spills over into questions you have not looked at for years.
The commercial cost lands in a specific place: anything new. A new sector, a new product, a larger size of client, an acquisition. Inside your existing business the unseen slice is small, because decades of contact have burned through it. Step sideways and it is suddenly enormous, while your confidence stays exactly where it was. That is where the surprises live — accreditations you do not hold and cannot get quickly, insurance levels you do not carry, payment terms and retentions that change the working capital arithmetic, and bids that take days of your own time rather than an hour. All of it is already known by the people doing that work.
How to use it this week
Write your five core beliefs about your market, and date each one
Cover why customers buy from you, where you sit on price and who your real competitors are, and put the year you last tested each one. Anything older than two years belongs in the fourth slice until proven otherwise.
Ring three customers and ask one question
“What nearly stopped you buying from us?” Do not defend the answers. Write them down.
Buy an hour from somebody who has already done it
Before any new market, product or acquisition, find somebody two years ahead of you and pay for their time. It turns the unseen slice into a list of things to sort out faster than anything else.
Run a pre-mortem on your biggest current bet
The technique is Gary Klein’s. Assume it is twelve months on and it has failed, then write down why. The failures your team can imagine are almost never the ones you have planned for.
Ask what would have to be true
Take your key assumption and finish the sentence: “for this to work, it would have to be true that…” Then check the one item on that list you have never verified.
Count your questions in the next management meeting
If you made twenty statements and asked two questions, you are managing entirely out of the first slice.
The mistakes to avoid
The first is treating your list of known gaps as the whole of your ignorance. It is the comfortable part, because every item on it is already a task.
The second is confusing years in the trade with current knowledge, and then hiring people who confirm it. A team assembled from your own way of thinking cannot see the unseen slice either, and a team who learned everything from you cannot see the out-of-date one at all. They are standing where you are.
Questions to ask yourself
- Out of 10, how confident are you about your market, and when did you last check any of it with somebody outside the business?
- What do you believe about your customers that you have not tested in the last three years?
- Who could tell you the uncomfortable truth about your business, and when did you last give them the chance?
- On your biggest current decision, what would you need to find out to be informed as well as decisive?
Where this fits in coaching
The Knowledge Pie is worked through in Personal Coaching, and it sits alongside two related mindsets: The Happiness Pie and Identity and Beliefs.
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Frequently asked questions
What is the difference between what you do not know and what you are wrong about?
One is a gap and the other is a false floor. What you do not know you do not know is everything you have never thought to ask about, and it shrinks only through contact with people who have already done the thing. What you are sure of that is no longer true is different and considerably more expensive, because it does not feel like ignorance at all. It feels like knowledge, and it was knowledge, several years ago. Pricing positions, customer motivations and competitor behaviour all age quietly. The practical defence is to date your core beliefs about your market and re-test anything older than two years.
How do I shrink the slice I cannot see?
Through contact, because thinking only works on questions you already have. The fastest and cheapest version is to find somebody two years ahead of you in whatever you are about to attempt, and pay for an hour of their time before you commit anything. An hour bought early converts a large amount of the unseen slice into a plain list of things to sort out. Ringing three recent customers and asking what nearly stopped them buying does the same job from the other direction, provided you write down the answers instead of defending against them.
What is a pre-mortem?
It is a technique from Gary Klein and it takes about twenty minutes. Assume it is twelve months from now and the decision you are about to take has failed badly. Then ask everybody in the room to write down why. The reversal matters, because asking what might go wrong produces polite caution, while asking why it did go wrong produces specifics. The failures your team can imagine are almost never the ones already on your risk register, which is the point of running it. Do it on your biggest current bet before the money is committed rather than after.
