The Hemlock Quarterly, an unassuming little newsletter that until recently was the chief perquisite of membership in the Hemlock Society, may have been the only radical publication in the United States whose subscriber rolls were dominated by affluent white women with gray hair. I’ve met many of these women, and I can attest that they were the sort of community-minded grandmothers who never littered, never stole anyone’s parking place, and always returned their library books on time. With the help of the Quarterly, these model citizens laid down a store of knowledge that would enable them, if they so…