In Ill-Structured Domains, Cases Are As If Not More Important Than Concepts

In traditional education we are taught a concept, and then the examples that illustrate that concept are treated as disposable. In STEM fields you’ll see engineers evaluating quality of thinking with a dismissive “you’re not thinking from first principles”. 

But n an ill-structured domain, then reasoning from first principles is very difficult. And that experts in ill-structured domains reason by comparison to previous cases, not by reference to first principles.