We can justify our decisions by how we feel, or so we believe. The problem, as psychology studies have shown, is that we often make up these reasons.

We're taught from childhood how important it is to explain how we feel and to always justify our actions. But does giving reasons always make things clearer, or could it sometimes distract us from our true feelings?

One answer came from a study led by psychology professor Timothy Wilson at the University of Virginia, which asked university students to report their feelings, either with or without being asked to provide reasons. What they found revealed just how difficult it can be to reliably discern our feelings when justifying our decisions.

Participants were asked to evaluate five posters of the kind that students might put up in their bedrooms. Two of the posters were of art – one was Monet's water lilies, the other Van Gogh's irises. The other three posters were a cartoon of animals in a balloon and two posters of photographs of cats with funny captions.

All the students had to evaluate the posters, but half the participants were asked to provide reasons for liking or disliking them. (The other half were asked why they chose their degree subject as a control condition.) After they had provided their evaluations the participants were allowed to choose a poster to take home.

So what happened? The control group rated the art posters positively (an average score of around 7 out of 9) and they felt pretty neutral about the humorous posters (an average score of around 4 out of 9). When given a choice of one poster to take home, 95% of them chose one of the art posters. No surprises there, the experimenters had already established that in general most students preferred the art posters.

But the group of students who had to give reasons for their feelings acted differently. This “reasons” group liked the art posters less (averaging about 6 out of 9) and the humorous posters more (about 5 to 6 out of 9). Most of them still chose an art poster to take home, but it was a far lower proportion – 64% – than the control group. That means people in this group were about seven times more likely to take a humorous poster home compared with the control group.

Here’s the twist. Some time after the tests, at the end of the semester, the researchers rang each of the participants and asked them questions about the poster they'd chosen: Had they put it up in their room? Did they still have it? How did they feel about it? How much would they be willing to sell it for? The “reasons” group were less likely to have put their poster up, less likely to have kept it up, less satisfied with it on average and were willing to part with it for a smaller average amount than the control group. Over time their reasons and feelings had shifted back in line with those of the control group – they didn't like the humorous posters they had taken home, and so were less happy about their choice.

Trivial pursuit

The source of this effect, according to the researchers, is that when prompted to give reasons the participants focused on things that were easy to verbalise; they focused on the bright colours, or funny content of the humorous posters. It's less easy to say exactly what's pleasing about the more complex art classics. This was out of step with their feelings, so in the heat of the moment participants adjusted their feelings (a process I've written about before, called cognitive dissonance). After having the posters on their wall, the participants realised that they really did prefer the art posters all along.

The moral of the story isn’t that intuition is better than reason. We all know that in some situations our feelings are misleading and it is better to think about what we're doing. But this study shows the reverse – in some situations introspection can interfere with using our feelings as a reliable guide to what we should do.

And this has consequences in adulthood, where the notion of expertise can mean struggling to discern when introspection is the best strategy. The researchers who carried out this study suggest that the distorting effect of reason-giving is most likely to occur in situations where people aren't experts – most of the students who took part in the study didn't have a lot of experience of thinking or talking about art. When experts are asked to give reasons for their feelings, research has found that their feelings aren’t distorted in the same way – their intuitions and explicit reasoning are in sync.

You might also see the consequences of this regularly in your line of work. Everybody knows that the average business meeting will spend the most time discussing trivial things, an effect driven by the ease with which each member of the meeting can chip in about something as inconsequential as what colour to paint the bike sheds. When we're discussing complex issues, it isn't so easy to make a contribution. The danger, of course, is that in a world which relies on justification and measurement of everything, those things that are most easily justified and measured will get priority over those things which are, in fact, most justified and important.

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