Dear Tablet readers of the twenty-second century, I’m writing to you because at this very moment your future is being decided. All the Very Important People of my era are meeting to decide what to do about climate change. But I don’t need to tell you this, because you’re living with the consequences. You’ll know whether we had the vision to change, or remained sightless, whether we were brave or timorous, generous or frightened, giving or taking.I wonder what your world looks like. Do great flocks of geese spell winter in your sky? Do the swallows still keep their springtime promise? I’d love to know if the cuckoos came back; if children, once again, are growing up within earshot of a song thrush. One personal favour – could you go and stand where my fr