I'll cheerfully refute it: lower animals do have the capacity to feel pain (so we shouldn't be cruel) but not, it appears, the capacity to hypothesize about the future - that is, pigs don't suffer anxiety over the probability of ending up getting slaughtered for bacon when they're sufficiently bulky.
this is a major qualitative difference between us and other animals (that we know about).
Since we really have no way to know for sure how much thinking about the future a pig does while confined on a grim industrial farm or exactly how much anxiety that pig experiences nervously worrying about the future, maybe we could give them the benefit of the doubt?
Well, if you concede the cruelty point, then you are pretty much in agreement with the animal liberation school; I'm unclear what's being refuted. The point is not that eating other animals is wrong--some believe so (not me), but it's a tough argument to swallow. Only that we have no right to make them suffer.
I think people often confuse the two because if you buy into the animal liberation argument, then the first thing to go is all the beef, pork, poultry, eggs and dairy that come from factory farming, i.e. everything. So functionally you wind up vegetarian, if not vegan. Now that we're seeing more places like Polyface Farms, Neeman Ranch, etc. open up, hopefully that situation will change in the future.
this is a major qualitative difference between us and other animals (that we know about).