Parkinson's Law
Published .
Parkinson's law says work expands to fill the time you give it. It started as a joke about government offices and became a widely quoted rule in productivity. It is half right. A short deadline does tighten a task. A short deadline on a whole goal is often how plans fall apart. Reverse journaling uses both halves.
Use the free tool: the goal deadline calculator
Parkinson's law: "Work expands so as to fill the time available for its completion." Cyril Northcote Parkinson wrote it in The Economist in 1955. A 1967 study found people given extra time did take longer, because they set slower goals for themselves. Reverse journaling applies it in the right place: an honest date for the finish, and a tight 45 minute box for today's step.
The short answer
Give each step a short, fixed box of time with a start time, so it cannot spread. Give the whole goal an honest date, worked out backward from the finish, so the plan survives contact with real life. Tight boxes, honest finish lines.
Where Parkinson's law comes from
Cyril Northcote Parkinson, a British historian, published the essay in The Economist on 19 November 1955. It was satire. His target was the British civil service, where he noted that staff numbers kept growing even as the work they managed shrank: more officials at the Admiralty as the fleet got smaller, more at the Colonial Office as the colonies went. He developed it into a book, Parkinson's Law: The Pursuit of Progress (UK edition 1958) (source).
The famous first line was the part that stuck: work expands so as to fill the time available for its completion. Most people now use it about their own week, not about bureaucracy.
Parkinson's law vs the planning fallacy
| Question | Parkinson's law | Planning fallacy |
|---|---|---|
| The claim | Extra time gets used up | We guess too little time |
| Points to | Shorter deadlines | Longer, honest estimates |
| Best for | One step, one session | The whole goal |
| Main risk | Deadlines you cannot meet | Padding that spreads |
They look like they disagree. They fit together once you split the goal from the step: be honest about the finish, be strict about today.
What the research says, carefully
- Extra time slowed people down. James Bryan and Edwin Locke (1967) gave one group twice the time they needed for an addition task and another group just enough. On the first three trials the extra time group took longer, and the goals people set for themselves explained the difference. When both groups later worked at their own pace, the gap went away (source). It was a small lab task, so treat it as a clue, not a law of nature.
- We already guess short. Roger Buehler, Dale Griffin and Michael Ross (1994) asked students when they would finish their honours thesis. On average they predicted 33.9 days and took 55.5, and about 30 percent finished by their own prediction. When people were asked to connect the estimate to their past experience, the optimistic bias went away in one study (source).
- When and where helps. Peter Gollwitzer and Paschal Sheeran (2006) pooled 94 tests of if-then plans that name when and where you will act, and found a medium to large effect on reaching goals (source). A step with a start time is that kind of plan. See implementation intentions.
- What no one has tested. We found no study that compares Parkinson's law style deadlines with reverse journaling. The case for combining them is a reasoned one, built from the findings above.
Treat these findings as a guide, not a promise. This is a planning habit, not medical or financial advice.
The catch: short deadlines on the wrong thing
The usual advice is to give yourself less time. That works for an email, a slide or a single chapter edit. Applied to a whole goal, it collides with the planning fallacy: you were already guessing short, and now you have cut the guess again. The deadline slips, it feels like failure, and the goal quietly gets dropped. Parkinson's law is a tool for the step, not the finish line.
How to use Parkinson's law backward
- Write the goal as done. Past tense, with a date: "On 30 April I launched my portfolio site."
- Check the date against your past. How long did the last similar project really take? If it took twice your guess, move the date. This is the honest finish line.
- Name the obstacle. What is most likely to stretch the work? Often it is open ended tasks like "work on the site".
- Step back to this week. Work back from the finish through milestones until you reach what must be true by Friday.
- Box tomorrow's step. One step, 45 minutes, with a start time and a place. Write what done looks like for that box, so the work has an edge.
- Stop when the box ends. Log what got done on your done list, even if it was less than planned. Tomorrow's box picks up from there.
Example: one project, two ways
Sam wants a portfolio site live by spring.
- Open ended: Sam blocks "work on the site" for a whole Saturday. By evening, the fonts have been changed four times and no page is finished. The work filled the day.
- Too tight: Sam sets "launch by next Friday". The last side project took six weeks. Friday passes, and the site goes on the someday list.
- Goal written as done: "On 30 April I launched my portfolio site", a date set after looking at how long the last project took.
- Backward plan for this week: finish the About page and pick three projects to show.
- Tomorrow's box: "7 pm, desk: About page first draft, 45 minutes. Done means 150 words and one photo."
- Tonight's log: "About page drafted, 170 words."
Same person, same site. The difference is where the tight deadline went.
When Parkinson's law alone is enough
- The task is small and clear, and the only problem is that it drags.
- You already know the finish date is realistic.
When to add reverse journaling
- You keep setting deadlines for a big goal and missing them.
- Your days fill up with busy work and the goal does not move.
- You are not sure what the next step even is.
Where this fits in Reverse Journaling
Reverse Journaling starts with the goal written as done, names the obstacle, plans back to today and ends each day with a done log. Parkinson's law shapes the 45 minute step. The 45 minute sprint and time blocking cover the box itself, and the two minute rule helps you start it.
Try it now
Write one goal as done, with a date. Ask how long your last similar project really took, and move the date if you need to. Then pick tomorrow's step, give it 45 minutes and a start time, and write one line for what done looks like when the time is up.
Questions
What is Parkinson's law?
Parkinson's law is the observation that work expands so as to fill the time available for its completion. Give a task a week and it tends to take a week; give it an afternoon and it often fits in an afternoon.
Who came up with Parkinson's law?
Cyril Northcote Parkinson, a British historian, in an essay in The Economist on 19 November 1955. It was a satire on how government offices grow, and he developed it into a book (UK edition 1958).
Is Parkinson's law backed by research?
Partly. In a 1967 lab study by Bryan and Locke, people given twice the time they needed took longer on the same task, and the goals they set for themselves explained the gap. The effect did not carry over once both groups worked at their own pace.
Should I just give myself less time?
For a single step, a short, clear deadline helps. For the whole goal, be careful: research on the planning fallacy found people already underestimate how long their own tasks take. Use tight deadlines for today's step and an honest date for the finish.
How do I use Parkinson's law with reverse journaling?
Write the goal as done with an honest date, work back to this week, and give tomorrow's step a fixed 45 minute box with a start time. The box stops the step from spreading; the backward plan keeps the finish date realistic.
What is Start From Done?
Manifest, with a plan. Start From Done helps you visualize and manifest your goals, dreams and the life you always wanted. You see your dream already done, name what could stop you, then get the steps back to today: backward milestones, an if-then plan, a first 45 minute step and a Done list for the evidence. It is free to start, needs no account, and your journal stays on your device unless you choose to share it.
Does manifesting actually work?
Picturing the dream on its own can backfire: studies by psychologist Gabriele Oettingen found that positive fantasies alone can lower the energy people put in. What research supports is pairing the picture with the obstacle in the way and a specific if-then plan, called mental contrasting with implementation intentions. Start From Done builds those steps in: see it done, name what could stop you, then take one 45 minute step today. It is built on research-backed goal steps, and no app can promise an outcome.