Known Knowns (Bite-size Article)

Source: Dev.to

Introduction

In the previous article I wrote about “Unknown Unknowns.”
This time, let’s look at Known Knowns—the things we already know and are fully aware of. When we create long‑term plans, unpredictable problems and unexpected obstacles can shake our plans. Equally important, however, is how effectively we identify and use our Known Knowns as the foundation of a plan.

What Are Known Knowns?

Known Knowns are “things we know, and know that we know.” They are stable, reliable pieces of information drawn from experience, patterns, and well‑understood facts. Because they are assumed to be true, they are often ignored, yet they form the non‑negotiable assumptions that must never be overlooked.

Examples of Known Knowns

• Your personal work pace and how long you can focus.
• Tasks that always follow the same pattern (prep work, cleanup, adjustments).
• Repeatable behavioral tendencies (morning person / night person, effect of work environments).
• The minimum time a certain task always requires.
• Predictable fluctuations based on health or daily rhythms.
• Productivity dips on weekends.
• The initial time cost of adopting a new tool.
• Coordination work required in large projects.

Why They Matter in Planning

If Unknown Unknowns are the forces that shake a plan, Known Knowns are the ground on which the plan stands. Ignoring these obvious constraints leads to avoidable failures—for example, assuming a task will take less time than it reliably needs, or overlooking the fact that coordination work is always part of a large project.

Treat Known Knowns as required, 100 % guaranteed constraints and build them directly into the structure of any long‑term plan. Doing so dramatically improves the stability and accuracy of the plan, allowing you to focus more effectively on the truly unknown elements.

Practical Tips

1. List your Known Knowns at the start of any project: identify personal rhythms, task durations, and recurring processes.
2. Make them explicit constraints in your schedule or project plan.
3. Review and update the list regularly to capture any new patterns that become predictable.
4. Communicate them to all stakeholders so expectations are aligned.

Conclusion

We often focus on weaknesses or new challenges, but what consistently supports our plans is the set of things we already know—our Known Knowns. Respecting these facts, alongside preparing for the unknown, elevates the quality of any plan, especially in uncertain environments.

Thank you for reading!