Yielding/obstinate is really hard to explain. I'll come up with a question that makes it clear, if indirectly, though. It's about focus on means vs. ends somehow though, not money or hobbies or whatever. I'm also not sure if the concept of "more yielding/obstinate" is relevant, just like asking whether a lark or an owl is more of a bird is not relevant. It's about prototypicality, not degrees of membership.