The Player of Games by Iain M Banks
This is characteristic Iain M Banks, from the Culture series. Gurgeh seeks relief from an ultra-secure life in the Culture by leaving it to play a game against the small and aggressive Empire of Azad: the Game of Life. This is the author’s vehicle, on this occasion, for a study in philosophy, science and psychology, supremely well expressed, with humour. One of my favourite books ever.