Peter Singer writes:
In earlier times, when original sin was taken more seriously than it generally is today, the suffering of animals posed a particularly difficult problem for thoughtful Christians. The 17th-century French philosopher René Descartes solved it by the drastic expedient of denying that animals can suffer. Animals, he maintained, are merely ingenious mechanisms, and we should not take their cries and struggles as a sign of pain, any more than we take the sound of an alarm clock as a sign that it has consciousness.
People who live with a dog or a cat are not likely to find that persuasive. Last month, at Biola University, a Christian college in southern California, I debated the existence of God with the conservative commentator Dinesh D'Souza. In recent months, D'Souza has made a point of debating prominent atheists, but he, too, struggled to find a convincing answer to the problem I outlined above.
He first said that, because humans can live forever in heaven, the suffering of this world is less important than it would be if our life in this world were the only life we had. That still fails to explain why an all-powerful and all-good god would permit it. Relatively insignificant as this suffering may be from the perspective of eternity, the world would be better without it, or at least without most of it.
(hat tip: Robin Varghese)