In "The New Yorker" (September 12, 2011), Larissa MacFarquhar has written a profile of Derek Parfit:
"How to Be Good"
"Around the mid-nineties, Parfit started reading Kant. He hadn't read him seriuosly before because he had always found him irritating - his appalling sentences (it was Kant, he felt, who had made really bad writing philosophically acceptable), his grandiloquence, his infuriating inconsistencies and glaring mistakes. He felt that the crucial Kantian idea of autonomy, for instance, was just a blatant cheat: Kant wanted there to be a universally valid moral law, and he wanted every person to have the moral autonomy to determine the law for himself, and he just couldn't have both those things at once.
"I asked a Kantian, "Does this mean that, if I don't give myself Kant's Imperative as a law, I am not subject to it?" "No", I was told, "you have to give yourself a law, and there's only one law". This reply was maddening, like the propaganda of the so-called People's Democracies of the old Soviet bloc, in which voting was compulsory and there was only one candidate. And when I said" "But I haven't given myself Kant's Imperative as a law". I was told "Yes, you have."
The thing that mattered enormously to Kant - moral autonomy, motive - didn't seem that important to Parfit. He thought that individual selves were less significant than other people thought they were, so he wasn't that interested in motive; he thought that moral truths existed independently of human will, so he wasn't going to place much value on autonomy in Kant's sense [....] Parfit's first love in moral philosophy was someone completely unlike Kant - Henry Sidgwick.... [....]
As he read deeper and deeper into Kant, he began to feel that the grandiloquence and inconsistency that had irritated him in the past were the product of an emotional nature so passionately extreme that it was simply incapable of Sidgwick's careful self-criticism. For Kant, something was never just good, it was necessary; there was little "most" or "some" in Kant, only "all" or "none". Parfit recognized that he, too, was an emotional extremist who found it difficult to accept answers that fell between everything and nothing. [....] He came to believe that Kant was the greatest moral philosopher since the ancient Greeks..."
See my previous posts on Derek Parfit's new book "On What Matters" and on reviews of the book.