Generalization is surely more than coverage? At least to me generalization is unveiling a principle or unifying lens that yields extended coverage, the principle being the meat. The coverage is the result of the unifying lens that makes previously different pieces look like cases of the "same" thing.

So it's kind of bottom-up/"data" driven as opposed to abstraction being more "engineered into" the system.

That is, to me abstraction is building things such that they look the same. Generalization is discovering things are almost the same if tweaked a little to look the same under a certain lens.

Does that make any sense? In this view I guess the generalizing lens can be become the basis for an abstraction. I would assume the loop is closed between the two somehow but I can't quite see it.