Apparently in this framework:

        1. Each constructor must "keep the game" by
		var self = prv.self = prv.self || {};
        6. Namespace collision with the name prv.self    

        2. Protected properties assigned via:
		prv.life_left = birth.LIFE_SPAN_LIMIT;

        3. Private members are just local to constructor function and hidden from ~descendants.
        4. Supplying named prv object at Class instantiation ~defeats the purpose of protected namespace.
        5. Diamond inheritance is non-commutative.