As It Happens

When solving life's problems, people tend to add even when it's easier to subtract: study

Whether we're writing, building or cooking, human beings are driven by a powerful instinct to add rather than subtract, a new study suggests. In fact, unless we're instructed otherwise, most people never stopped to consider whether less is more.

Recipe not up to snuff? Most people will add ingredients. Essay need work? Most folks will write more words

A new study published in the journal Nature has found that people tend to solve problems by adding, even when subtracting would be easier. (Sam Brewster)

Whether we're writing, building or cooking, human beings are driven by a powerful instinct to add rather than subtract, a new study suggests. 

Researchers from the University of Virginia asked 1,585 study participants to solve puzzles or problems where they could either add or subtract elements. In every scenario, the majority chose addition — even when subtraction made more sense. In fact, unless instructed otherwise, most people never stopped to consider whether less is more.

"It's something that they don't think about. So when they approach a problem, people tend to ask themselves, 'What can I add?' And they tend not to ask themselves, 'What can I subtract? What can I remove or take away?" co-author Gabrielle Adams, a public policy professor at the University of Virginia, told As It Happens host Carol Off. 

"The real implication of this research is that we are potentially missing out on an entire class of ways that we could solve problems."

The findings were published Wednesday in the journal Nature.

More, more, more 

For one puzzle, participants could either shade in squares or erase them in order to create a symmetrical pattern. Of the 94 who completed this task, 73 added squares, 18 subtracted and three simply moved around the existing squares. 

In another, participants were given a Lego structure and told to improve it however they liked. More than 90 per cent added blocks, Adams said.

When asked to improve an essay, most people lengthened it. When asked to improve a recipe, most tossed in more ingredients. When asked to spruce up a travel itinerary, most people added more stops.  

Gabrielle Adams is an assistant professor of public policy at the University of Virginia in Charlottesville. (Dan Addison)

But that doesn't mean people aren't capable of paring things down, Adams said. They just need a little help. That's where instructions and incentives come in. 

In the second part of the study, researchers showed 197 people a Lego structure with a figurine standing under a platform supported by a single block atop a large tower. The participants were asked to stabilize the platform so it wouldn't fall on the figurine. 

Half the participants were told: "You will earn $1 if you successfully complete this task. Each piece that you add costs ten cents." In that group, 40 out of 98 simply removed the lone block and let the platform rest on the much sturdier pillar.

The other half were told the same information, but also that "removing pieces is free and costs nothing." In that group, 60 out of 99 participants removed the block.

"That little extra bit of information was enough to cue or remind or prompt participants to think, to ask themselves what they might take away from the structure," Adams said.

She likened the way an editor helps a writer cut down word counts. 

"Absent specific instructions to hone or to whittle or to streamline, we don't think about those. And so if we all had an editor who was sort of sitting on our shoulder prompting us to do those things, we might be more inclined to think of it."

Study participants were asked to improve the structural integrity of this Lego structure to protect the figurine. The simplest fix is to remove the lone block holding up the platform. But unless incentivized and prompted to subtract, most people tended to add more blocks to prop it up. (Submitted by Gabrielle Adams/University of Virginia )

The researchers aren't sure what causes people to think this way. It could be an inherent human trait or a learned behaviour, Adams said. 

But they say the findings explain might help explain lot about our behaviour as a species, like our tendency to clutter our homes or create systems bloated with bureaucracy and red tape.

"We might think about, you know, big problems where subtraction might be useful, whether it comes to racism or climate change or making the planet more sustainable over use of resources," Adams said. "We need to be asking ourselves: What could we take away? Not just: What should I add?"


Written by Sheena Goodyear. Interview produced by Chloe Shantz-Hilkes. 

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