The words of its writers are part of the texture of Dublin, an invisible counterpart to the bricks and pavement we see around us. Beyond the ever-present footsteps of James Joyce's characters, Leopold Bloom or Stephen Dedalus, around the city centre, an ordinary-looking residential street overlooking Dublin Bay, for instance, presents the house where Nobel Laureate Seamus Heaney lived for many years; a few blocks away is the house where another Nobel...