Cone of Plausibility


The cone of plausibility is a visual aid that can help us organize our thoughts and understanding of how likely various scenarios are to occur. While it is not specifically a method by itself, it can help communicate the scenarios that have been developed in a different way.

When to use it?

The cone of plausibility is useful when a group is trying to visually describe how likely we believe various scenarios are to occur in the future, as compared to a business as usual model.

How to do it?

  1. Begin with a list of critical uncertainties.

  2. Define the timeline the group is working on (e.g. 20-30 years) and the boundaries for the future state that the group is prepared to consider as ‘possible.’ For example, the group may decide to work within the boundaries that it is possible that, in the future: all health care will be publicly funded on one extreme, and no health care will be publicly funded on the other extreme. Within those boundaries, other potential scenarios exist that could be considered ‘plausible,’ probable,’ or ‘preferable.’

  3. In a chart, describe briefly how each critical uncertainty could unfold in the future under a ‘business as usual’ future (probable based on what we currently know), one or two ‘plausible’ futures, and a ‘preferable’ future based on where the group would like to be. These descriptions form the scaffolding of scenarios that can be fleshed out in more detail later.

  4. On the cone (as shown in the diagram) plot how far each scenario deviates from the future that, based on current knowledge, seems probable.

Requirements
People: 2-10

Time: 30-60 minutes, or more

Pros and Cons
Pros:

  • Allows us to consider as many critical uncertainties as a group determines is necessary for their scenarios (rather than the 2*2 matrix, which focuses on only two)
  • Visualizes how far different scenarios seem to be from the probable future state.
  • Can aid in communicating the likelihood of various scenarios

Cons:

  • Is based on subjective knowledge and perspectives of participants
  • Scenarios must be developed (e.g., as per the instructions above) prior to using the cone of plausibility (which is not really a method for developing scenarios on its own).