Paper or a biodegradable material made from corn starch? This question has replaced the more traditional "Paper or plastic?" at San Francisco supermarkets, and the New York City Council may follow suit. The bill that council speaker Christine C. Quinn is pushing would not go as far as the San Francisco law, which banned plastic bags outright.

But it would impose a new burden on city supermarkets by requiring them to collect, transport, and recycle used bags. The supermarkets will surely pass on the cost of this new requirement to the consumer in the form of higher prices, yet to our knowledge the plastic-bag debate is proceeding in the absence of any serious cost/benefit analysis. The main knock against plastic bags is that they are not biodegradable. But organic alternatives to plastic, while biodegradable in theory, break down very slowly inside airless landfills, where they actually take up more room than plastic materials. Seeing no compelling evidence that the benefits of yet another mandatory recycling program outweigh the costs, our take on this bill is simple: Bag it.