lence to a cap-and-trade proposal. My discussion has much in common with Kotlikoff (2010), Chalmley, Kotlikoff and Polemarchakis (2012), Admati and Hellwig (2012). It also builds on Cochrane (2010, 2011). The larger points in this essay build on Cochrane (2013b). 3 Electronic copy available at: EFTA0