‘Do as I say, not as I do’ applies to philosophy as much as any other discipline. The search for the Good Life (what the Ancient Greeks termed eudaimonia) does not presuppose a good life, or a particularly ordered one. David Hume, the Scottish Enlightenment thinker whose presence haunts Jennie Erdal’s first novel, spent a lifetime trying to find an accommodation between philosophy and ‘the common life’. But it didn’t stop him, like Descartes, suffering a nervous breakdown as a young man. Hume’s response to the ‘disease of the learned’, as depression was sometimes known in the eighteenth century, was to play backgammon and take long daily hikes that stilled his whirring mind. The consolations of philosophy went only so far. 

Three centuries later that remains true and, in The Missing Shade of Blue, Erdal delights in exposing the limits of reasoning. For Harry Sanderson, a drink-sodden relic of Edinburgh University’s philosophy faculty, the day job offers little