This month’s letter is from 1984 and sees Lewis asking the cartoonist Roz Chast whether she will allow him to use her ‘Parallel Universes’ cartoon as the frontispiece for On the Plurality of Worlds. Chast said ‘no’ since she was about to use it as the cover for her own book, Parallel Universes — which is a shame, because it would have been perfect! The cartoon is copyright Roz Chast; many thanks to her for allowing us to post it here.