He concludes (I'm taking an excerpt, read the whole thing by clicking on the links):
my own view is that veganism is a kind of harmless and in many ways sweet eccentricity (who can get mad about people who love animals?), but it crosses the line into a moral error insofar as people think it is morally obligatory or morally superior to non-vegan lifestyles.But, he is a liberal, at Chicago via UT. He is used to some abuse.
I expect stating this plainly will open me up to lots of abuse, but since vegans do not, as far as I can see, have any arguments that can appeal to shared background attitudes, they probably have no choice. As A.J. Ayer noticed long ago, "It is because argument fails us when we come to deal with pure questions of value, as distinct from questions of fact, that we finally resort to mere abuse."
The overall point, those who do not have arguments that can appeal to shared background attitudes, have only abuse to argue with. Combined with the triumph of value ethics, every disagreement becomes a proof of moral failing in those one disagrees with, rather than a disagreement.
Interesting to consider.