What a great book! It's fun to imagine teaching a course based on this and Stephen Mulhall's book, along with The Lives of Animals and some other readings too, probably. It's also fun to see how each author responds to the others and, in some cases, to the discomfort of being a non-vegetarian in such company (I would be uncomfortable too). I want to try to write at least something about each part of the book, starting with the introduction by Cary Wolfe.
Wolfe provides a fine introduction that brings Derrida into the mix as well. I didn't find this all that helpful, but then I don't understand Derrida very well. (Generally he seems to want to say: "That's not quite right. There's something you're missing out, but I can't really tell you what it is." And this might well be true, but reading his way of trying to gesture at what is being missed never helps me very much, possibly because I don't spend enough time on it.)
What struck me most was this bit: "when Diamond affirms Costello's assertion that "I know what it's like to be a corpse," Derrida's response would be, "No, you don't. Only the other does, ..." (p. 23). I don't know how to read this except as saying that, according to Derrida, one cannot know what it is like to be a corpse. And that sounds too metaphysical for my taste. If anyone knows what it is like to be a corpse it isn't from time served as a corpse or from reading richly detailed descriptions of the experience of being dead. So it would (seem to me to) be reasonable to ask Costello or Diamond "How on earth do you know that?" or "What can you possibly mean?" And I wouldn't be surprised if they had interesting answers to those questions. But to say (relatively) simply, "No, you don't," appears to take what they mean as both straightforward in meaning and false. It might be the latter, but I don't see how it could be the former.
I might now accuse myself of making exactly the same mistake with Derrida or Wolfe, but it's less obvious (to me) that they couldn't be mistaken here. Also, Wolfe is suggesting a reading of Costello, according to which Costello is less worth reading than I had thought. This makes Wolfe less worth reading, too, since what he offers is a commentary on her text. Costello, on the other hand, gives us a commentary on death and animals, which are still interesting subjects even if Costello gets them wrong.