Many people have tried to figure out how creativity works from looking at creative products.  It is clear that when you explore things that are clearly seen as creative, they often break a number of core constraints that have characterized a field in the past.  The impressionist painters moved beyond a focus on images to explore light and to capture moments in time.  Newton switched from thinking about acceleration as a property of objects to a property of the forces acting on them.  Cloud computing emerged from a desire to have documents available to everyone in an organization regardless of the computer they were working from. 

From these demonstrations, it is tempting to conclude that creativity is all about removing constraints from the problem.  Indeed, this point was made explicitly by Alex Osborn when he formulated rules for what he called brainstorming in the 1950s.  He told people to ignore as many constraints on the problem as possible when formulating new ideas.

This seems like great advice. 

The problem is that it doesn't work.

Research by Tom Ward, Steve Smith, Ron Finke and their colleagues points out that most thinking involves taking a path of least resistance.  One way to see this in your own life is to examine how often your actions involve doing what you have done in the past.  You typically take the same route home from work, each similar things at familiar restaurants, and sit in the same seat in the conference room at group meetings.  These habits reflect that you are retrieving your past actions from memory and then engaging them again.

Retrieving things from memory happens automatically, whether you are pulling out past actions or elements of your prior knowledge.  The situation you are in calls things to mind that you experienced in the past which share similarities with that situation.  Those memories influence what you are thinking about--even when you are trying to be creative.

For example, Tom Ward has done a number of studies where he asks adults to draw animals that don't exist or beings from alien planets.  He asks people to be as creative as possible.  Despite those instructions, people base their fictitious animals on animals they know about.  Even when drawing alien beings, their creatures are generally symmetric like Earth animals and have typical sense organs like eyes, noses, and mouths.  Indeed, the more intelligent the creatures are supposed to be, the more they tend to resemble humans.

That is, people are following a path of least resistance.  They are retrieving information from memory and then altering that information to reach a creative outcome.

It turns out that the fewer constraints you place on the creative solution to your problem, the more freedom you have to use your memory to help you solve it.  Throwing out constraints can actually make you less creative.

Instead, you want to place constraints on the solution to your problem.  Those constraints will make most of the memories that you retrieve impossible to apply to the situation.  If you tell people to draw intelligent alien creatures that cannot have eyes, noses, or mouths, then they cannot apply what they remember.  As a result, they have to seek new ways for the creatures to eat, sense, and communicate.

Placing constraints on the solution to a problem does make it less likely that people will come up with a solution at all.  It may be hard for them to satisfy all of the constraints.  However, those solutions they do come up with are judged to be more novel than the ones people generate with no constraints.

If constraints make people more creative, then how come many creative solutions appear to break through constraints?  The trick to using constraints to make you more creative is to select constraints that keep you from suggesting the same kinds of solutions that have been recommended in the past.

To return to the idea of cloud computing, you start with a key constraint:  a document should be editable by any member of a group.  To solve that problem, you have to understand why that was a problem.  Prior to the cloud, document files were typically stored on a particular person's desktop computer.  By instituting the constraint that documents be broadly accessible, the existing method that everyone stored their documents on their own computer had to be changed.

Ultimately, holding on to some constraints will force you to relax others in ways that lead to novel and interesting solutions to problems.