The appealing pitch of Gray’s book is that sober life is not just good for you, it’s actually better fun, too. Sobriety has had a bad rap, being equated since time immemorial with seriousness and dull, muted colours. In fact, sober life offers you the whole rainbow: rather than spending all day sleeping off your hangover, you can leap out of bed at seven and go for a 10-mile run, join your friends for a jolly brunch, before spending the afternoon “deep diving into Aladdin’s Cave vintage shops for bargains”. You can still date, and dance and have sex. You can go to parties and weddings. You can do anything a drunk person can do – with the added bonus that you are unlikely to make an idiot of yourself while you’re at it.