When actresses like Hathaway (and, to a lesser degree, actors like Gyllenhaal) decide to bare all, they inevitably justify the choice by saying it was integral to the character. Of course nudity is integral to the character; so is buying groceries and paying the bills, yet directors don’t feel compelled to show that stuff. There’s nothing remarkable about a character taking off her clothes to have sex—that’s how most of us do it. Conversely, a person’s refusal to undress during sex gives us a world of information about who he is (three words: Eliot Spitzer’s socks).