“If the glove doesn’t fit you must acquit.”
We’re all aware of this famous line used by OJ Simpson’s lawyer Johnny Cochrane. It was, some say, the line that set OJ free (at least until he got himself into more trouble). That's because humans are more likely to believe a phrase that rhymes than one that doesn’t. Does "If the glove doesn’t fit, you must not find him guilty" have the same power? No.
This is an example of cognitive fluency. Cognitive fluency is a measure of how cognitively (mentally) easy it is to think about something. The easier something is to think about, the more likely we are to like it, remember it and believe it’s true.
Why? Because we are hardwired to think less. The less we have to think about things, the less energy we need to consume. The human brain accounts for only 2 per cent of our body mass but consumes 20 per cent of our of energy. We’re wired to use that power-hungry brain as little as possible, as back in the day it was difficult to get calories in (finding the food, killing it, cooking it and so on). The principle remains built into us to this day, and for this reason we think as little as we need to.
This thinking-less philosophy leads to us habitualising our behaviours wherever possible. Approximately 40 to 50 per cent of what we do is habitual, and we prefer the familiar and well-trodden over the new and novel.
In marketing, this has a particularly interesting paradoxical conclusion, which is that we prefer brands that don’t make us think. In fact, our favourite brands will make us think much less than unfamiliar brands—and therefore we are more drawn to them. So as a marketer you should ensure your brand offers consumers cognitive fluency. Make the purchase process as simple and easy as possible, such as by paying attention to details such as font, grammar and positioning.
But here's the conundrum: What do you do if your competitors have cognitive fluency already stitched up? How do you get consumers to pay attention to what you have to offer when your competitors are gliding consumers in for a sale?
The answer just might be disfluency. This is the act of purposefully creating something that requires more cognitive load to process.
Here’s a simple, well-used example by psychologists Schwarz and Song (see reference). They asked people a seemingly simple question: "How many animals of each kind did Moses take on the Ark?"
Answer it now. As I’m sure you did, most people answered "Two". However, you’ve gotten it wrong, and you’ve answered this question even though you know that it wasn’t Moses who took two of every animal onto the ark, it was Noah. (If you were not exposed to a Christian education growing up, then just assume that for many Christians this is a well-entrenched piece of knowledge.)
It was easier to answer ‘two’ than to stop and think about every word in the question. It was set up that the answer was going to be two. You have a question that starts talking about arks, and animals and the bible. Everyone knows that two of each kind of animal went on. We don’t expect an error in the question, so we miss it. We create cognitive fluency.
However, what Schwartz and Song found was that they could get people to question the statement just a little more by writing the question in an ugly, difficult to read font. What happened then was that there was a low level of processing fluency, and this, as predicted, led to more people detecting the misleading nature of the question and identifying that the correct answer was ‘zero’—Noah took the animals on the ark, not Moses.
Participants were less likely to rely on their spontaneous association when the font was difficult to read, resulting in improved performance on the question. So if you want to make people pay attention and break the ‘cognitive fluency’ flow, it helps to make your audience work a little harder.
Perhaps this is the reason why I love advertising that is just a little bit wrong, doesn't quite make sense or requires just a little bit of work from the consumer. McDonald’s ‘I’m lovin’ it’ line, grammatically incorrect, is a wonderful example of disfluency, as is, perhaps, the #likeagirl Super Bowl campaign—a phrase so often used negatively is turned on its head, inviting people to reconsider its purpose.
Changing behaviour using cognitive fluency is fast becoming a significant weapon in the marketer’s behaviour-change armoury. Either make it Teflon-easy for the consumer, or really give them something to think about.
Adam Ferrier is global chief strategy officer and consumer psychologist at Cummins&Partners. See all of his 'Unobvious Observations". He is also the author of The Advertising Effect: How to Change Behaviour (Oxford, 2014).
- Song, H., & Schwarz, N. (2008). Fluency and the detection of misleading questions: Low processing fluency attenuates the Moses illusion. Social Cognition, 26, 791–799.
- For more on cognitive fluency, read Drunk Tank Pink by Adam Alter