If the festive season's enforced togetherness is proving a torment, curl up in a corner with this manifesto for the shy, sensitive loner.
Drawing on new research, Cain argues a heartfelt case for the value of a thoughtful, self-contained and contemplative personality in a world that worships the "extrovert ideal". In fact, her world is mainly the modern US. Her - rather noisy - defence of introvert outsiders depends on a parochial view of cultural norms. All the same, refugees from the tyranny of party-time jollity will love this eulogy of the quiet ones.