Cavell notes that both Costello and Diamond are horrified not only by what is done to animals but also by the widespread indifference of the humanity that eats them. He invites us to think of two different visions of the world. Quite so, but it also comes down to innumerable minutiae, whose effect may differ from attentive person to attentive person (p. 148)I take it that the indifferent are the inattentive, who elsewhere are called blind. But I take it also that one can be attentive without becoming vegan (Costello isn't, for instance) or even completely vegetarian (one might eat only humanely raised and slaughtered animals, perhaps). And there could be degrees of attentiveness, rather than just two categories of people: the attentive and the inattentive. Perhaps this would explain some people's going further than others towards pure veganism, though I doubt it could be the whole story.
In response to McDowell's suggestion that we talk of "putative reality" rather than "reality" (since we might not share Costello's reaction to it), Hacking writes:
Perhaps we should speak not of the difficulty of reality but of the difficulty of experienced reality, of reality as experienced. This allows Elizabeth Costello her horror at the meat industry, the reality as she experiences it. It excludes the madman in his cabin because delusions are not reality as experienced, even if they are as painful to the deluded man as any experience he has ever had. (p. 153)The point is that "putative reality" might be a delusion, and Costello does not seem to be deluded, even if we don't react as she does. This seems like a good idea, although there could be trouble ahead if we start trying to distinguish between reality as experienced and reality as it is in itself. Can't we understand why the reality might cause her to react that way even if we do not react that way ourselves?
On Hughes's poem about the photograph, Hacking points out that the men died at Gallipoli, which is still remembered as a tragedy, in a war that has an important part in British, Australian, and Canadian mythology. (For a right-of-center view of what it meant, see Larkin's poem MCMXIV. For a left-of-center view see The Pogues singing about Gallipoli.) It could be that some sense of this mythology is necessary to appreciate the full force of Hughes' poem.
Finally, Hacking questions why Diamond should count instances of goodness or beauty as difficulties of reality, and the question is worth asking. But it's only such instances that throw us that Diamond is talking about, as I read her. Most goodness and beauty is not like this. I would think that difficulties of reality are wherever you find them--whatever you find hard to live with or make sense of (as long as you are not deluded) might count as such a difficulty. Diamond says that in at least one case of goodness "what is capable of astonishing one is its incomprehensibility" (quoted on pp. 166-167). Hacking says that, "Her point is that we cannot comprehend it by 'taking it apart.'" (p. 167). He wants to say that we can simply wonder at such goodness, without (also) wondering at our inability to comprehend it. But I'm not so sure. I'm not sure whether there is any real disagreement between Diamond and Hacking on this point, but I'm also not sure that Hacking has got it quite right either (nor that I have, of course). To call something wonderful is very close to calling it incomprehensible. So wondering at something's incomprehensibility is like wondering at its wonderfulness. It's almost the same thing, only squared or intensified. But if Hacking exclaims "Wonderful!" at some act of generosity and Diamond gasps "Incomprehensible!" do they really have the same appreciation of it? Hacking seems to have in mind a reaction that is not a difficulty of reality, that does not upset the normal flow of one's life, whereas Diamond seems to have something potentially transformative in mind. I don't know.