[russellperry]

"What if objects exist as encapsulations, and the communicate via messages? What if code re-use has nothing to do with inheritance, but uses composition, delegation, even old-fashioned helper objects or any technique the programmer deems fit? The ontology does not go away, but it is decoupled from the implementation. Here's how."

This is standard OOP 101 advice. 'Prefer encapsulation to inheritance' has been axiomatic in OO literature for over a decade. GOF and all the GOF-derived texts emphasize this.

OOP <> Inheritance

Inheritance is only one tool in the OOP toolbox, and probably one of the least important. OOP itself is only one conceptual tool in the programmer's toolbox, alongside procedural and functional tools. Learn them all, learn their strengths and weaknesses, and learn how to apply the right tool to the right problem.