Most of us are overconfident about how much we understand things – this simple intervention can help

When we're asked how much we understand the workings of everyday things like vacuum cleaners or computer printers, most of us massively overestimate our own knowledge. This overconfidence extends beyond objects to more abstract matters, such as our comprehension of political policies, and collectively the phenomenon is known as "the illusion of explanatory depth".

One already established antidote is to ask people produce a detailed explanation of whatever it is that they think they understand – after doing this, most of us come to realise the true modesty of our knowledge. However, as an intervention or "cure" for reducing over-confidence, producing full explanations is impractical because it is time consuming and unappealing. But now a team of psychologists at Washington and Lee University has demonstrated that it's not necessary to have people generate full explanations – merely asking them to reflect briefly, in a very specific way, on their knowledge is enough to effectively combat overconfidence.

Across nine studies involving hundreds of people recruited via Amazon's Mechanical Turk website, the researchers tested the effectiveness of what they call "Reflecting on Explanatory Ability". Before estimating their understanding of various objects, including vacuum cleaners, crossbows, treadmills and umbrellas, participants were instructed to:

"Carefully reflect on your ability to explain to an expert, in a step-by-step, causally-connected manner, with no gaps in your story how the object works".

Spending a few seconds doing this was enough to substantially reduce people's estimates of their own knowledge, almost as much as spending time typing out a full explanation, and far more than simply spending time on unguided reflection (in the unguided condition, the instruction was to "carefully reflect on your understanding of how the object works").

The researchers believe that "Reflecting on Explanatory Ability" works because it forces people to assess the complexity of the object they're thinking about and to get a sense of the number of gaps in their knowledge. Supporting this interpretation, the researchers found that the guided reflection instructions were not as effective when they lacked the specific wording "in a step-by-step, causally connected manner". Similarly, adding the additional, later instruction to "estimate how many steps it would take to explain how the parts enable the object to work" did not enhance the "Reflection on Explanatory Ability" intervention, suggesting that this is what the intervention already prompts participants to do.

Also consistent with the idea that the "Reflection on Explanatory Ability" intervention works by provoking participants to perform a quick complexity assessment, the researchers found that their intervention was less effective at correcting people's confidence in their knowledge of less complex objects (the researchers acknowledged this means there is still a useful role for generating full explanations in these cases).

In another test, the researchers checked and confirmed that the benefits of their "Reflection on Explanatory Ability" intervention were not due to participants producing silent explanations in their heads – that is, the intervention was just as effective whether participants reflected for five or twenty seconds (if they were engaging in covert explanation, then the intervention should have been more effective after twenty seconds).

In the final study, the researchers showed that their intervention doesn't just help combat people's overconfidence in their understanding of objects, it can also reduce their overconfidence in their understanding of political policies (such as the idea of merit-based pay for teachers), and as a consequence, it makes their attitudes towards those policies more moderate.

Johnson and his team concluded that "Reflection on Explanatory Ability; REA" is a "rare metacognitive tool in the arsenal to combat our proclivity to overestimate understanding" and that "perhaps REA can help us gain the wisdom to which Socrates was referring."

Further reading

Johnson, D., Murphy, M., & Messer, R. (2016). Reflecting on Explanatory Ability: A Mechanism for Detecting Gaps in Causal Knowledge. Journal of Experimental Psychology: General DOI: 10.1037/xge0000161