The problem may be in any domain e.g. mathematical, applied sciences, computer programming, etc.<p>Any books (or maybe courses) that built up the mental model that you now use to attack any problem you encounter and design working (maybe elegant) solutions to? Is it at all possible that a book(s) can do that?
Lawvere & Schanuel, <i>Conceptual Mathematics</i><p>It got me thinking about abstraction (and working with concrete representatives) both more abstractly, and with more use of concrete formal representations.<p>(rather than myopically concentrating on solely an abstraction or the reality, consider also the relations between the two levels)