Comments on Wittgenstein's Philosophical Investigations should be respectful and not defensive: they should follow his own guidelines whenever possible, but critically, not in blind admiration. And they should include explicitly discussions of critics of his philosophy and their impact. Their natural starting point is the generally agreed on: the book says something new about rules. He first deemed the rules (of logic) meaningless, even though they are understood and should be obeyed; in his Philosophical Investigations he changed: he says there, following some rules is right, and this makes them (not meaningless, TLP, §85, but) empirical (PI, §84)!