What makes the right level of abstraction right? Seems like the units of abstraction have to be amenable to application (analogy), but rightness is fluid. If you have a turing machine, it might make more sense to write a JS compiler first because of the familiarity and perceived difficulty of translating your thoughts, but that's a statistical process of your own head. If you're a fresh mind, you would never create a JS compiler. The aggregated feedback of our social consciousness over time is what sets the 'rightness' of any approach by modulating the difficulty and expressiveness of each concept to each individual.