VOICE OVER: How would you go about fixing this wobbly bridge?
How about changing this grid pattern, to make it symmetrical?
GABRIELLE ADAMS: When people solve problems, typically they think
well what can add that will make it better?
PARTICIPANT: Wait, also left to right...
PARTICIPANT: I see there's a couple of green boxes I need to change...
PARTICIPANT: Oh, I could have got, this is not... I should have taken.
GABRIELLE:We tend not to ask ourselves what can we take away from it, what can we subtract
what can we remove that might still make something better?
PARTICIPANT: (Laughs)
PARTICIPANT: Oh dear.
VO: Leidy Klotz is an engineer who’s fascinated by the psychology of design.
He started to notice that people’s first instinct is often to add.
LEIDY: One real epiphany was playing Legos actually with my son Ezra,
who was about 2.5 at the time and we were building a Lego bridge, basically.
And so the two columns on the bridge, one was longer than the other one. And so, to make the bridge level,
I turned around to grab a block to add to the shorter column.
And by the time I turned around, Ezra had just removed a block from the longer column.
VO: Leidy realised that, in many cases, removing an element actually leads to a better design.
LEIDY: One example that we love is the balance bikes, the pedalless miniature bikes that allow two year olds to ride.
And if you've seen a little two year old going on these things,
I mean, it just makes you disappointed that you didn't have it when you were a kid.
But the breakthrough was just taking away the pedals.
VO: It took decades for someone to think of removing the pedals, rather than adding stabilisers.
And yet through history, people have championed different kinds of minimalism.
LEIDY: People are familiar with Marie Kondo right, tidying your home, but you know, going back you think Leonardo da Vinci,
his famous definition of perfection is when there's nothing left to take away.
And my personal favorite is Lao Tzu which is,
I'm paraphrasing here but, to gain knowledge, add things every day, to gain wisdom,
subtract things every day.
And what's interesting about this is all throughout history, there have been these reminders,
but the fact that we need a reminder is some of the best evidence that our brains don’t think of it on their own.
VO: Leidy's been working with a team of behavioural scientists to try and figure out why our brains default to adding
and what, if anything, can be done to change this.
GABRIELLE: So in our first study, we showed people a Lego structure that looked like this,
and the instructions were to improve the structure so that it could hold a brick above a small figurine.
VO: Most of the participants added bricks for support,
that is unless the experimenters reminded people that they could add or remove bricks.
GABRIELLE: Half of participants were told that each piece that you add costs 10 Cents
and the other half of participants were told that each piece that you add costs 10 Cents, but removing pieces is free.
So when we reminded participants that removing pieces is free, participants
were much more likely to remove pieces from the structure than when we didn't remind them.
VO: Without reminders, only 41% of people took away the extra brick.
But when cued, 61% went with the cheaper solution.
Could it just be that taking things away doesn’t occur to people?
Gabrielle wanted to know what other factors affected this behaviour,
for example, what if people tried the task while distracted by something else?
GABRIELLE: We gave them a 10 by 10 grid.
PARTICIPANT: During the task you'll be given a set of patterns. Change each pattern
so it's perfectly symmetrical from left to right and from top to bottom.
GABRIELLE: Subtracting would require fewer clicks than adding,
and the instructions were to use as few clicks as possible.
VO: But there was another task that participants were asked to do at the same time.
PARTICIPANT: God. Right, press 'F' everytime you see a five.
PARTICIPANT: (exhales) Okay... VOICE OFF SCREEN: (laughs)
PARTICIPANT: So many fives.
PARTICIPANT: Oh there's another five, ok, there's another five, I've not even... got a time to start the task...
...two fives, oh lots of fives...
...um, finally I think I've got it, ok done.
GABRIELLE: What we find is that that when they are under what we call cognitive load,
so when they are distracted, when their attention is taken up by another task,
that's when it tends not to occur to people that they could solve the task
by removing those extra squares.
PARTICIPANT: Oh, I could have got, this is not, I should have taken. Oh dear. Let me retreat.
VO: When people have more time or attention or cognitive resources,
they’re more likely to find the more efficient solution.
But adding things was still the default response across a range of examples and conditions studied.
GABRIELLE: So, this is a novel heuristic. Heuristics are basically mental shortcuts
that people take when they process any kind of information. And so by identifying one way
in which that information processing is biased, that it's biased toward additive solutions and
not thinking of subtractive ones, I really think that we're, we're onto something kind of new here.
VO: Gabrielle and the team think that this previously unrecognised bias in thinking could have big implications.
GABRIELLE: when we overlook subtraction, that's when we get things like overburdened schedules, busy people,
increasing red tape in institutions, and we're missing out on opportunities, opportunities to make our lives more fulfilling,
institutions more effective and more efficient,
and even to make the planet better, more livable, more green, more sustainable.