I’m referring to the stunning passage in California, by nearly a 2-to-1 majority, of an animal rights ballot initiative that will ban factory farms from keeping calves, pregnant hogs or egg-laying hens in tiny pens or cages in which they can’t stretch out or turn around. It was an element of a broad push in Europe and America alike to grant increasing legal protections to animals.

The idea popularized by Princeton scholar Peter Singer — that we have ethical obligations that transcend our species — is one whose time appears to have come.

Professor Singer wrote a landmark article in 1973 for The New York Review of Books and later expanded it into a 1975 book, “Animal Liberation.” That book helped yank academic philosophy back from a dreary foray into linguistics and pushed it to confront such fascinating questions of applied ethics as: What are our moral obligations to pigs?

What we’re seeing now is an interesting moral moment: a grass-roots effort by members of one species to promote the welfare of others. Legislation is playing a role, with Europe scheduled to phase out bare wire cages for egg production by 2012, but consumer consciences are paramount. It’s because of consumers that companies like Burger King and Hardee’s are beginning to buy pork and eggs from producers that give space to their animals.

Jeremy Bentham, the philosopher who 200 years ago also advocated for women’s rights, gay rights and prison reform,  responded to Kant’s lack of interest in animals by saying: “The question is not, Can they reason? nor, Can they talk? but, Can they suffer?”