There's no doubting that humans love animals. We post their photos all over the internet, we feed them from our tables, and we include them in our holiday cards..."Love Lisa, Mark & Whiskers!"

From harpooning whales to clubbing harp seals to experimenting on chimpanzees, their welfare is even frequently elevated to a cause celebre. In many cases, we treat them as people, so why not recognize them legally as such by granting them "non-human personhood"?

We put that seemingly simple question to James Serpell, a professor of animal ethics and welfare at Penn's School of Veterinary Medicine. In response, he brought up the case of a primate who was kept in reportedly horrific conditions in someone's basement.

"Treating [animals] like someone's property that they can keep in the basement in a cage is not appropriate," he says, adding that we all know that mistreating animals we share so much with genetically is inherently wrong. But, he continues, "when you start to think about the implications of giving animals non-human personhood it does appear to open a legal can of worms that could have very complicated and drastic ramifications throughout society."

Farming, research, even pet ownership would change dramatically, he argues.

Should we prioritize treating animals well, and if so, which ones? Or are we fooling ourselves to think we don't still rely on our domination of other species? 

"We're very torn over these issues," says Serpell.