Co-Evolution of Problem and Solution Spaces in Creative Design An Essay by Nigel Cross & Kees Dorst www.researchgate.net Between the two spaces What the prototype tells youSolution to evaluation and back againIn terms which must be alteredPrimitive design
The Design of Design (Cambridge Engineering Series) A Book by Gordon Clegg www.amazon.com What the problem is
What the problem is Sometimes the problem is to discover what the problem is. The heart of systems engineeringComplete and consistent requirements problemsdesignux