Add - Subtract - Change
The basic add-subtract-change idea-creation technique is easy
to use. It is particularly good for use in redesigning things,
but it can be used for any type of problem. You just start with
the existing "solution" or current state of affairs
and ask what you can add, subtract or change. In answering this
you will stumble upon all sorts of ideas.
We will use a bicycle to demonstrate how to use this technique.
To come up with a new product, for example, we would look at
an existing bicycle and ask:
1. What could we add?
Maybe a radio could be built into the handle bars (or at least
the controls could be there, with the rest located elsewhere).
Perhaps a map holder could be attached to the handle bars.
I'm sure this has been done by a few people who travel long distances
on their bicycles.
We might add a pet-carrier up front, so you can bring your
cat along for the ride (okay, I'll stop looking at the handle
bars as I write this).
Maybe a bike could have a built-in retractable lock. I like
the idea of it fitting inside the tubular frame somewhere.
2. What could we subtract?
We might take away some of the gears, or all of them. I've
always thought that for casual users, three speeds are more than
Subtract some of the weight? Lighter is better for most bicycle
Lower the price? This may seem a bit off-topic, but then the
whole idea of this technique is to stimulate new ideas, so go
where your mind takes you.
3. What could we change?
We could make the tires reflective for safety (the sidewalls).
We could put a hole in the seat for men's comfort, or find
a new type of padding that does a better job of protecting us
Could we make the gears shift automatically?
We might used something other than spokes for holding the
Notes and Tips on This Problem Solving Technique
As you can see, looking for things to add can require a bit
of imagination. It sometimes helps to break that part into components.
In the example of a bicycle we might first consider what we can
add to the handlebars, and then move on to the wheels or other
On the other hand, looking for things to subtract can be very
systematic. You just have to look at everything item by item
and ask what would happen if it was removed or lessened in some
way. It can become a process of looking for changes, as when
we consider removing handlebars and are then left with the question
of how the bicycle would be steered (shifting one's body?).
The last question -- What could we change? -- is where you
get to be very systematic and imaginative. Item by item
you look at every aspect of the existing solution to imagine
ways in which you could alter it, replace it, or redesign it.
Put the three questions together and you have a powerful way
to quickly and creatively solve problems and generate new ideas.