A Fickle Pendulum assays belief and doubt through three historical figures - St. Thomas the Apostle, Galileo Galilei and Laura (Riding) Jackson - and uses them to pivot into wider thematic worlds. The writing is thoughtful, exploratory and never weighed down by its subject matter, and the language vibrant and rich in metaphor. The reader ineluctably mixes Paul Scully's meditations with his or her own.