Why Our Brains Miss Opportunities to Improve Through Subtraction

Klotz, whose research explores the overlaps between engineering and behavioral science, teamed with three colleagues from the Batten School of Leadership and Public Policy on the interdisciplinary research that shows just how additive we are by nature. Batten public policy and psychology faculty, assistant professor Gabrielle Adams and associate professor Benjamin Converse, and former Batten postdoctoral researcher Andrew Hales, collaborated with Klotz on a series of observational studies and experiments to study the phenomenon.

When considering two broad possibilities for why people systematically default to addition — either they generate ideas for both possibilities and disproportionately discard subtractive solutions or they overlook subtractive ideas altogether — the researchers focused on the latter.

“Additive ideas come to mind quickly and easily, but subtractive ideas require more cognitive effort,” Converse said. “Because people are often moving fast and working with the first ideas that come to mind, they end up accepting additive solutions without considering subtraction at all.”

The researchers think there may be a self-reinforcing effect.

“The more often people rely on additive strategies, the more cognitively accessible they become,” Adams said. “Over time, the habit of looking for additive ideas may get stronger and stronger, and in the long run, we end up missing out on many opportunities to improve the world by subtraction.”

Klotz has a book that takes a wider view of the topic, “Subtract: The Untapped Science of Less,” coming out a week after the Nature paper. Although the timing is coincidence, both the paper and book are products of the interdisciplinary and collaborative research environment at UVA, he said.

“It’s an incredibly interesting finding, and I think our research has tremendous implications across contexts, but especially in engineering to improve how we design technology to benefit humanity,” Klotz said.

Selected additional coverage of the researchers findings:

• The Academic Times, “People default to additive strategies when problem-solving, even if subtracting is more efficient”
• Ars Technica, “When asked to fix something, we don’t even think of removing parts”
• Behavioral Scientist, “Subtract: Why Getting to Less Can Mean Thinking More”
• CBC Radio, “When solving life's problems, people tend to add even when it's easier to subtract: study”
• Dagens Nyheter, “That's why it's so hard to be a minimalist”
• Daily Mail, “Less is more! People tend to add extra elements when asked to improve objects, ideas and situations - but removing them is actually more effective, study finds”
• Inverse, “You need to start using this psychology-based productivity hack”
• Science News, “People add by default even when subtraction makes more sense”
• Scientific American, “Our Brain Typically Overlooks This Brilliant Problem-Solving Strategy”