See, that's one area where the digital would distinctly lag behind the traditional, old paper world; the metaphor would collapse here. It's sad if it was true that Apple out of all companies would hinder progress in this regard, or make it impossible for their competitors. There's nothing more natural, while reading a paper book and highlighting passages in it, than to highlight text spanning several paragraphs, or parts of paragraphs. For Apple, to make this natural mode of studying and marking up digital texts on their devices, very difficult or impossible, defies reason.
