Porgy and Bess opens with this lullaby, in which Clara’s child is lulled to sleep with promises of ease and security. In the context of the opera, we know that none of this is true: the craps game is about to begin, Clara will die, and the baby will be passed on to Serena. It will become just another child leading a life of danger and contingency on Catfish Row, staged within Gershwin’s sociological imaginary. But cut off from the larger work, and sung as a stand-alone standard, we can hear something else in “Summertime,” and it’s slightly more comical: eutopian plenitude (cotton and catfish, and generalized wealth) cannot prevent the intrusive, raw desire of a bawling infant (and praise be that, someday, it will be off on its own). Life itself interdicts its own perfection.