Being really neither about the future nor consistently about sex, Future Sex is a disappointment. Its pitch is a big idea on an urgent theme – a kind of state of the insemination address, or The Way We Frig Now. But what Emily Witt delivers is an accidental exemplar of another modern malaise: the essay collection ransacked from various outlets and contorted into a fictive autobiographical and intellectual arc.

The conceit is this: Witt finds herself, at thirty, a member of the growing class of the single. In theory, she enjoys a life of endless erotic choice. In practice, this is not what she would have chosen at all: ‘if in my early thirties the future would