The gist of it:

We tend to overthink and overcomplicate things

Far too often, we convince ourselves that things need to be difficult and that if we aren’t in some sort of mental or physical turmoil, then we are doing something wrong or not trying hard enough. As a result, we can sometimes actively seek out the path of most resistance and intentionally make things more complicated than they need to be

Subtract to solve is a concept of removing or subtracting something to simplify a situation, or solve a problem.

How to use it:

We often assume the bigger or more complicated a problem is, the more time or effort is required to solve it.

When faced with the problem of balancing the Lego structure above, your first instinct might be to add a block to the shorter column. Considering the solution would require more time and effort (finding an additional block), removing the block on the longer column might turn out to be a better solution.

The next time you look at a problem, ask yourself these questions:

What would this look like if it were easy?

What if I could only subtract to solve this?

e.g. If you think something will take 2 days to solve, ask yourself:
What if I only had 2 hours to solve this? What would the solution look like?

The constraint forces us to come up with simple creative solutions that focuses on reducing complexity rather than adding to it.

Deep Dive

When researchers at the University of Virginia asked 1,585 study participants to solve puzzles or problems where they could either add or subtract elements, the majority chose addition, even in cases when subtraction made more sense.

In fact, unless instructed otherwise, most people never consider that less could be more. 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.

In our lives, we all have a tendency to add when thinking about solutions - I have too much stuff, I need more storage. There’s space in our living room, let’s get more furniture. I just got this new skirt, let me get a new top and shoes to go with it.

This might explain our collective behaviour as a species, like our tendency to clutter our homes or create systems bloated with bureaucracy and red tape.

For many generations, the standard way to learn how to ride a bicycle was to add training wheels. But in recent years, many parents have opted to train the kids with balance bikes, pedal-less two-wheelers that enable children to develop the coordination and balance needed for bicycling; a skill that would not be as easily acquired with an extra set of wheels.

In some European cities, urban planners have found that getting rid of traffic lights and road signs actually makes streets safer; an idea that runs counter to conventional traffic design.

So think about this the next time you encounter a problem:
What can you remove? What can you subtract? What can you minimise?

Reframing the urge to add ingredients helps reduce the complexity of the problem at hand, leading to simpler, more creative solutions.

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