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PMI lesson plan

1. PMI lesson plan

PMI: Plus, Minus, Interesting

The treatment of ideas

This lesson plan is for the PMI lesson workcard.

The PMI is a crystallization of the open-minded attitude into a tool that can be used deliberately. This is a very basic lesson which is introduced at the beginning so that the PMI process itself can be used as a tool in the course of subsequent lessons. Instead of just deciding whether or not you like an idea, this thinking operation requires you to make an effort to find the good points (P=Plus), the bad points (M=Minus) and the interesting points (l=lnteresting) about an idea. The interesting points are those which are neither good nor bad but are worth noticing. The PMI is a way of treating ideas, suggestions and proposals. The natural reaction to an idea is to like or dislike it, to approve or disapprove. If you like an idea, it is very unnatural to look for the negative or minus aspects. If you dislike an idea it is very unnatural to look for the positive aspects or plus points. It is equally unnatural to pick out the merely interesting aspects of an idea.

Using the PMI as a deliberate operation gives students a means of by-passing the initial reaction to an idea. Their thinking style moves from defending an initial response to exploring the situation with a more open mind.

Once the PMI has been practiced as a tool it can be asked for in subsequent lessons:

"Do a PMI on that idea."

The PMI is never intended to prevent decision or commitment but to ensure that this happens after both sides of the matter have been considered and not before.

In simple terms the PMI operation enlarges the view of a situation; without it, emotional reaction to an idea narrows the way we look at it.

See the lesson workcard for an example of a PMI on the idea that all seats should

be taken out of buses.

Further example: Windows should be made of transparent plastic instead of glass.


  • They would not break as easily.

  • They would not be as dangerous when broken.


  • Plastic would be degraded by sunlight.

  • Plastic would get scratched very easily.


  • Perhaps windows could be different colors if they were plastic.

  • Perhaps we take it for granted that glass is best since we are used to it.

  • It would be safer to have interchangeable window panes for different seasons.


(see Practice section of student workcard)

Normally practice items 1, 2 and 3 are used one after the other. But a teacher may choose to substitute later items. If there are many students then they work in groups.

Practice item 1. By law all cars should be painted bright yellow.

The students use PMI for 3-5 minutes. If there are groups, then one group is requested to give Plus points and the other groups or individuals can add further points. Another group is then asked to give Minus points and finally a further group is invited to provide Interesting points.



  • Yellow cars would be easier to see at night or in fog, so there would be fewer accidents.

  • Car showrooms would be able to let you have the car immediately instead of your having to wait for the color you want.

  • Cars would be more likely to be treated as a means of transport than as status symbols.


  • It would be rather boring.

  • Paint manufacturers and advertisers would have a hard time.

  • It would be difficult for the police to chase a particular car or trace stolen ones.


  • Should the car color be of use to the owner or to everyone else?

  • Do people drive different colored cars differently?

Practice Item 2. People should wear badges showing whether they are in a good mood or bad mood that day.

Students do a full PMI but this time the objective is to try to guess the two Plus points, the two Minus points, and the two Interesting points which the teacher holds. Time allowed is 3-5 minutes, at the end of which each group can offer one suggestion at a time for either P, M, or I points, when a group guesses one of the example answers given below, the teacher indicates this. When no more points are forthcoming the teacher gives out the remaining example answers.

Example answers:


  • You could steer clear of people in a bad mood.

  • People might make more of an effort not to be in a bad mood if it was going to show.


  • People would not be honest about wearing the right badge.

  • People in a bad mood who needed cheering up would be avoided instead.


  • With some people you can tell their mood from their faces anyway.

  • Do people prefer to hide their moods or to show them?

Further practice items.


Individuals or groups do either P points, M points or I points as instructed by the teacher. Time allowed is 3 minutes. One group is then designated to give the P points, another to give the M points and another to give the I points. In each case the other groups can add further points as they wish.

Discussion and further practice

Open a discussion on the process of using PMI.

Invite students to look at the learning points and select the principle they think is the most important. Ask if the students can think of other learning points or situations when PMI would be helpful.

Practice items can be used as essay topics or given to students to work on in their own time.

These de Bono Thinking Lessons are free to use by parents, guardians and teachers. (This means on this website, or to print and use in home or in the classroom. Not for further distribution or commercial use). 

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