Forthcoming (August 2011) Future Science edited by Max Brockman, Vintage Press, New York. Here are just a few recent headlines from major newspapers: “HOLY MACKEREL AND OTHER GUILT-FREE FISH” (New York Times), “GUILT-FREE SUSHI” (Christian Science Monitor), “CoD AND CHIPS? MAKE IT POLLOCK IN GUILT-FREE GUIDE TO SEAFOOD” (The Times of London), and “A GOOD APPETITE; SEAFOOD, EASY AND GUILT-FREE” (New York Times). It is perhaps unsurprising that a set of tools has emerged to assuage this guilt and, in the case of seafood, reform the appetite.” These tools aim to divert demand from one type of seafood toward another. Wallet cards, iPhone apps, and eco-labels tell consumers which fish ought to be and ought not to be eaten. Shoppers in Europe have been given rulers, so that they can measure fish and avoid buying juveniles. Guilt abounds in many situations where conservation is an issue, not just in the response to overfishing. Harried by guilt, one mother reuses her daughter’s bathwater for her own bath. Los Angeles shoppers refuse to buy blueberries imported from Chile, because of the fuel consumed in shipping them. Another woman feels guilty about the natural habitat lost to cocoa cultivation and refuses to buy chocolate, prompting her husband to say that she took the joy out of his Almond Joy.® Just as the devout purchased guilt-alleviating papal indulgences in the Middle Ages, guilt-ridden consumers today buy carbon offsets, LED light bulbs, and hybrid cars and can be guided to something approaching sanctimony by books like The Virtuous Consumer, The Rough Guide to Shopping with a Conscience, and The Eco Chick Guide to Life: How to Be Fabulously Green. The problem is that environmental guilt, while it may well lead to conspicuous ecomarkets, does not seem to elicit conspicuous results. One supermarket chain introduced signs at the fish counter to show the most and least sustainable seafood: Sales of the green-tagged SJ. Jacquet, et al., “Conserving wild fish in a