The last chapter of "The Death and Life of Great American Cities" by Jane Jacobs offers a very thorough and pertinent description of what the author calls "habits of thoughts" for complex problem solving. In the context of this book about urban environment, Jacobs starts by describing "the kind of problem a city is", explaining that cities pose the same kind of problems than life sciences and that the "tactics to understanding both are similar". She then provides the reader with 3 propositions (I removed every reference to cities on purpose):
1) To think about processes: (...) objects can have radically different effects, depending upon the circumstances and contexts in which they exist (...) once one thinks about city process, it follows that one must think of catalysts of these processes, and this too is of the essence (...) these processes can be understood by anybody (...) 2) To work inductively, reasoning from particulars to the general, rather than the reverse: (...) inductive reasoning is just as important for identifying, understanding and constructively using the forces and processes that are relevant (...) too complex to be routine (...) always made up of interactions among unique combinations of particulars and there is no substitute for knowing the particulars
3) To seek for "unaverage" city clues involving very small quantities, which reveal the way larger and more "average" quantities are operating: (...) statistics almost tell nothing about how the quantities are working in systems or organized complexity. (...) To learn how things are working, we need pinpoint clues (...) The "unaverage" can be physical, economic, cultural, social (...) "unaverage" quantities are also important as analytical means - they are often the early announcers of the way various large quantities are behaving or failing to behave, in combination with each other.
Why do I blog this? thinking about qualitative aspects of research, this description resonates with diverse methodologies I use; it's definitely close to user experience analysis, as well as critical foresight methods.