It's from the Tao Te Ching:

"Heaven and earth are ruthless, and treat the myriad creatures as straw dogs; the sage is ruthless, and treats the people as straw dogs."

One might accuse this of falling afoul of the appeal to nature, but that would assume a fact not in evidence, to wit, that Annoyance's motivations resemble that of a typical LW poster (to the extent that such a beast exists).