A problem boundary is the imaginary line between what a problem is, must be, should be, or could be, and what it isn't, mustn't be, shouldn't be, or couldn't be. This approach works by creating awareness of the different components of the boundary and then seeing how far they can be loosened. Here are some ways of making a boundary more visible.
NOT-ing the problem statement Take each significant term in a problem statement and define it more clearly by saying what it is not, for example:
How to develop (not replace, alter, reduce,…)
the motorway (not other roads, airlines, ships, ... )
network (not piecemeal)
to allow for (not compel)
the gradual (neither imperceptible nor rapid)
replacement (not augmentation)
of rail (not air, ships, …)
transport (not pleasure use, prestige use)
Boundary conditions not mentioned in the problem statement may often be found by looking elsewhere e.g. budgets, policy statements, market analyses, etc., and by 'asking around'. Sometimes you may need to 'read between the lines'. Once a boundary feature has been identified dearly, then it is usually relatively simple to ask yourself and/or others involved:
'Would it make the problem any easier to solve if this part of the boundary could be altered in some way?'
'If so, under what circumstances could it be altered or ignored?'
It may be easier to get temporary leeway around a boundary by discreetly 'bending' it and making sure nothing goes wrong, than by trying to get formal permission to alter it. Many are familiar with the saying ‘Remember it is easier to ask for forgiveness than for permission.'