Here is another piece of my exchange with Professor Block. It, too, has been edited some.
I can’t resist this one. If we humans violate animal rights by killing them, don’t they violate each other’s rights by doing the same thing? Is the wolf a murderer when it kills the deer?
The wolf “is a murderer” when he kills the deer to the same extent that the disturbed 6-year-old “is a murderer” when he kills one of his classmates. (Unfortunately, murders of the latter type do happen.) The analogy hinges on the suggestion that the perpetrator (and, we might add, the victim) lacks the cognitive abilities and moral sense of fully developed human beings.
With this analogy set up, let us be careful not to misunderstand what the wolf’s attack on the deer implies. The fact that Child A–because of his limited cognitive and moral development–has no misgivings about hitting, kicking, or even killing the innocent Child B obviously does not mean that you and I are justified in wantonly mistreating Child B. By the same token, the fact that the wolf (again because of cognitive and moral limitations) has no misgivings about killing deer does not mean that you and I are justified in killing deer. The reason is simple: the fact that cognitively/morally underdeveloped beings unflinchingly engage in cruel acts does not exonerate cognitively/morally developed beings who engage in those acts.
Another point might also speak to your concerns: Some people feel that if deer and other animals actually have rights, then vegans should support hunting wolves (and other carnivores/omnivores) as a way of basically giving these animals the death penalty for killing prey. This is a mistake. Wolves, like murderous children, do not understand the significance of their actions; thus, even if we believe in the morality of retribution, it is totally disproportionate to “punish” wolves with death (or, frankly, with anything serious). In contrast, morally and cognitively developed human adults who kill deer, sheep, cows, etc. may indeed make themselves liable to a serious legal response in a just system. (To be clear: as an opponent of the death penalty who is skeptical of retributive justice, I most certainly do not advocate the death penalty for those who kill animals.)
As always, looking forward to getting your thoughts.