Book excerpt: While almost everyone has heard of human rights, few will have reflected in depth on what human rights are, where they originate from and what they mean. A Philosophical Introduction to Human Rights – accessibly written without being superficial – addresses these questions and provides a multifaceted introduction to legal philosophy. The point of departure is the famous 1948 Universal Declaration of Human Rights, which provides a frame for engagement with western legal philosophy. Thomas Mertens sketches the philosophical and historical background of the Declaration, discusses the ten most important human rights with the help of key philosophers, and ends by reflecting on the relationship between rights and duties. The basso continuo of the book is a particular world view derived from Immanuel Kant. 'Unsocial sociability' is what characterises humans, i.e. the tension between man's individual and social nature. Some human rights emphasize the first, others the second aspect. The tension between these two aspects plays a fundamental role in how human rights are interpreted and applied.