"Nigel Warburton: Most of us, most of the time are most interested in other human beings. If you start including all kinds of animals, how do you work out what to do?
"Peter Singer: It does complicate things. Just as, if you're a white European in the eighteenth century, it complicated things to have to consider the interests of Africans. That interferes with your profitable trade in slaves. But even though it's more complicated, it's still something we ought to do. Now it is true that the calculations can't be done with any precision at all, but in some situations we can make rough comparisons and sometimes it's pretty clear that we're inflicting more suffering than is justified by the benefit that we're getting out of it. One of those situations is factory farming.
"In factory farming, we confine animals in conditions that for their entire lives make them miserable. They can't satisfy their basic needs, neither physically in terms of moving around, exercising, having comfortable bedding, nor socially and psychologically in terms of mixing with the right kind of social groups suited for their species. Laying hens might be suffering for their entire lives. Breeding sows might be in stalls too narrow for them even to turn around, let alone walk, for most of their lives.
"We have to ask: what do we get out of this? Well, we produce food a little more cheaply. But we are not starving, and we can afford to pay a little more for our food. I don't think there's much doubt that that's not something that can be justified if we give equal consideration to the sufferings of the hens and the pigs."
