DORIS LESSING'S NEW book, The Grandmothers, contains four short novels, each of which could have been developed into a full-length book. Lessing is a skilled practitioner of the art of brevity, as her many short stories demonstrate. In these novellas, she sketches characters and situations with wonderful energy and economy, deftly providing just what is required to understand the complex relationships at the heart of each tale. The effect is bracing: the speed and ease of the narratives make the emotional revelations all the more precise and shocking. There is a thematic connection which makes sense of the stories' CO-publication, since the impact of one tale influences the reading of the rest. Put at its simplest, they are about the moments of vision that determine the course of a life.

The title story concerns that perennially fascinating cause célèbre, a mature woman's interest in an adolescent boy. In novels such as The Summer Before the Dark and the more recent Love, Again, Lessing has written with great insight about the sexuality of older women. For reasons which gradually become obvious,