Consumption 12 ■ Keynes& C function 9 3 a Fisher intertemporal choice 765 a Life-cycle hypothesis a Permanent hypothesis a Random-walk hypothesis Pull of instant gratificationConsumption ◼ Keynes & C function ◼ Fisher & intertemporal choice ◼ Life-cycle hypothesis ◼ Permanent hypothesis ◼ Random-walk hypothesis ◼ Pull of instant gratification