EB RECHTIN

 
(When) asking skilled architects ...what they do when confronted with highly complex problems... (they) would most likely answer, "Just use Common Sense." (A) better expression than 'common sense' is 'contextual sense'-a knowledge of what is reasonable within a given content. Practicing architects through eduction, experience and examples accumulate a considerable body of contextual sense by the time they're entrusted with solving a system-level problem...
- Eb Rechtin - Systems Architecting Creating & Building Complex Stems, Prentice Hall, 1991