🏆 Subtract Your Way to Success

The science of "less is more"

Oct 24, 2021

When we tackle challenging problems, we use mental shortcuts to speed up our decision-making process. But shortcuts come with risks: They can make us miss perfect solutions that lie along other routes.

One common mental shortcut may be blinding us to 50% of the possible solutions we could find in the world. When we face a problem, our initial instinct is to think about what we can add to the scenario in order to make progress: What tools can we introduce? What can we buy to make life easier? What ingredients should we add to this recipe?

But the best solution isn’t always about what you can add. It’s often about what you can subtract.

➖ The power of subtraction

In a paper published earlier this year, a group of researchers led by Gabrielle Adams at the University of Virginia tested people’s problem-solving skills. They gave people a set of problems and analyzed their solutions to see how much they involved adding a feature versus subtracting a feature.

I’ve recreated one of their simplest tasks below. Here’s the question: What’s the easiest way to make this grid perfectly symmetrical in top-to-bottom and left-to-right directions by switching some tile colors between white and blue?

A task from Adams et al. (2021). How do you make the grid perfectly symmetrical by changing the colors of individual tiles?

The correct solution is to remove the blue from the four tiles in the top left corner. But the researchers found that only 49% of people in their experiment used this solution.

The task isn’t particularly difficult, but people were following an automatic instinct to add rather than subtract blue tiles. When the researchers offered people more thinking time by presenting a couple of practice grids with similar problems, they boosted the correct solution rate for the puzzle to 63%.

So it’s not that people can’t comprehend subtractive solutions or that they realize a subtractive solution and then dismiss it. It’s rather that their minds default to additive problem-solving rather than subtractive problem-solving as soon as they begin thinking.

Consistent with this idea, people were less likely to come up with subtractive solutions if they had to do multiple things at once (i.e. they had a “high cognitive load”). That’s because when people are under pressure—whether it’s time pressure or multitasking pressure—they’re more likely to rely on instinctual but suboptimal mental shortcuts.

The subtraction problem doesn’t just apply to visual puzzles. The researchers repeated their tests using more realistic scenarios too.

In one experiment, they showed people the structure of a mini golf course and asked them for ideas on how to improve it. Only 28% of people submitted a subtractive idea such as “remove the sand trap”. When the researchers explicitly reminded people that they could either “add or subtract” features from the course, a larger 43% of people came up with at least one subtractive idea. Once again, people were capable of coming up with subtractive solutions if they were given a little nudge, but their initial instincts consistently let them down.

In a final set of observations, Adams et al. examined archival data to see whether additive solutions would also dominate a naturalistic setting outside the world of labs and experiments. They found a scenario in which an incoming university president had asked stakeholders to submit suggestions for how to improve the university. So they analyzed that list of 1201 suggestions, looking at the ratio of additive to subtractive ideas.

A measly 11% of suggestions were subtractive (e.g. “eliminate legacy admissions”). The other 89% of ideas were focused on what could be added to the university (e.g. “more study abroad grants”).

Overall, across more than 10 experiments and observational analyses, the researchers found a consistent proclivity toward additive rather than subtractive problem-solving strategies.

Our instinct for additive thinking might explain why so many of our institutions are bogged down by rules and regulations. Rather than removing mediocre or outdated rules, we prefer to add new rules to regulate the old rules. Our desire to solve problems by doing more rather than less might even explain some of the excess in our overthinking minds and overcrowded schedules.

It’s possible that the best solutions to major global problems like environmental sustainability, political corruption, and law enforcement are subtraction strategies involving less activity and less intervention. But if decision makers are too eager to adopt additive strategies, subtractive strategies will have a harder time rising to the top of the agenda.

As Adams et al. note in their paper, the reason we often need to remind people that “less is more” is because they so frequently overlook it.

⭐️ Takeaway tips

Start subtracting: Take a moment to think about some of the superfluities and clutter in your life. What could you remove to streamline a little? You could unsubscribe from services you no longer use, cancel any unnecessary meetings for next week, or donate some clothes to a charity.
Reconsider a problem: Have you ever missed a useful subtraction strategy in your work? Could any of your current tasks benefit from a subtractive mindset? It’s likely that you’ve used an additive solution at some point when a subtractive solution would have been better. Finding examples from your own life will make you more aware of how mental shortcuts can occasionally be hindrances rather than advantages.
Don’t try too hard: Actions can make a problem much worse. Sometimes, the best thing to subtract from a situation is your attention. We spend half our lives ruminating over things we could have done differently or things we should do in the future, but so much of this energy is wasted on events beyond our control. Give yourself a break and stop planning for a day.