Comment by groundzeros2015

I responded to that. It’s nonsense which doesn’t work:

> And the reason why the canonical bird as a subclass of animal doesn’t work, is it’s extremely difficult to divide the world into strict categories (are you Aristotle)

What behavior are you going to out in vehicle? Here are a few potential subclasses you’ll need to consider:

- hang glider

- wheelies

- train

- skis

- lawn mower

- windsurfing board