An important function of art is (and always has been) to bear witness.

The 18th century seems to have been a time in which the idea of animal rights was beginning to take root in some minds. The artist Jean-Baptiste Oudry’s imagery may strike us as neutral that way–neither dismissing nor advocating that animals have their own lives and legitimate perspectives.

But that the debate of animal rights was very much in the air at the time was made clear in a shocking set of prints by artist William Hogarth, The Four Stages of Cruelty from 1750-51. What a vast difference in mentalities between these two contemporaneous artists!

While Oudry was painting for his courtly patrons, Hogarth was making prints for popular distribution–visually to assert that cruelty to animals is on the same ethical continuum as cruelty to one’s own species.

Of course words can help to bear witness too, as Matthew Scully did in his recent book, Dominion, where he gains access to the hellish world of factory farms, whaling, and commercial safaris. But such books can be easily avoided. What ethicist Peter Singer points out, so rightly, is the need for artists to expose what is otherwise hidden: the 100 billion animals who suffer unspeakably in the US every year because of factory farming.

We need the vision of artists, including photographers (similar to the Depression’s Dorothea Lange) to expose the horror deliberately hidden from sight.