Evils of the Naturalistic Fallacy

I saw a link today to this article, concerning the prospect of engineering predation out of the ecology in the interest of eliminating suffering (see also the Hedonistic Imperative), and was reminded of this particularly marvelous quotation from Terry Pratchett (Vetinari speaking):

“I have told this to few people, gentlemen, and I suspect never will again, but one day when I was a young boy on holiday in Uberwald I was walking along the bank of a stream when I saw a mother otter with her cubs. A very endearing sight, I’m sure you will agree, and even as I watched, the mother otter dived into the water and came up with a plump salmon, which she subdued and dragged on to a half-submerged log.

“As she ate it, while of course it was still alive, the body split and I remember to this day the sweet pinkness of its roes as they spilled out, much to the delight of the baby otters who scrambled over themselves to feed on the delicacy. One of nature’s wonders, gentlemen: mother and children dining upon mother and children.

“And that’s when I first learned about evil. It is built into the very nature of the universe. Every world spins in pain. If there is any kind of supreme being, I told myself, it is up to all of us to become his moral superior.”

This, of course, is peculiarly applicable to the Eldraeverse in explaining both their identification of entropy and evil, and in quite why so many people and organizations in the Empire are quite so comfortable “playing God”. Someone has to, they might very well say, on the grounds that if anyone does hold that post already, the prevalence of this sort of thing in the universe demonstrates clearly – even before we bring up minor issues like the inescapable cosmic force of decay, belike – that the present incumbent is incompetent, insane, or quite simply monstrous.