More than two centuries after its initial publication in 1781, Immanuel Kant's Critique of Pure Reason remains perhaps the most influential text in modern philosophy. Kant himself claimed his work as a revolutionary document and insisted that it changed the discipline of philosophy as thoroughly as Copernicus had changed astronomy 300 years earlier, when he said the Earth revolved around the sun and not the other way round.

On the Genealogy of Morality was written in 1887 when Friedrich Nietzsche was at the height of his powers as a philosopher and master of German prose writing. Here, he criticizes the idea that there is just one conception of moral goodness, dissecting the contemporary practice of morality and looking at it from a historical viewpoint. Rather than following a metaphysical or religious approach, Nietzsche adopts a naturalistic framework, which is grounded in history and natural science, to understand our concepts of good and evil in the Christianized Western world.

In his 1807 work Phenomenology of Spirit, G. W. F. Hegel introduced the world to his philosophical system. His most influential work - and the culmination of the German Idealist movement begun in the late 18th century as a response to the works of Immanuel Kant - the book remains one of the undisputed classics of Western thought.

What might society look like if we were brave enough to emerge fully from the shadow of the Christian God? The German philosopher Friedrich Nietzsche explores this intriguing question in his 1886 work, Beyond Good and Evil. Going further, Nietzsche then asks of his "philosophers of the future" that they take on the challenge of supplying humanity with new ideals to live by.

Geneva-born thinker Jean-Jacques Rousseau's famous work of political philosophy from 1762 is based on a give-and-take theory of the relation between individual freedom and social order: the social contract that gives the work its name. Rousseau thinks about the issue by starting with what is known as the state of nature, a lawless condition where people are free to do what they like, governed only by their own instinctive sense of justice. People are free, but they are also vulnerable to chaos.

How do those in power exercise that power over a state's citizens? French thinker Michel Foucault's 1975 work Discipline and Punish looks to answer this question by investigating the prison system. Foucault does not believe that the modern-day system developed out of reformers' humanitarian concerns. He argues that prison both created and then became part of a bigger system of surveillance that extends throughout society.

"If you want to know what anthropology is, look at what anthropologists do," write the authors of Social and Cultural Anthropology: A Very Short Introduction. This engaging overview of the field combines an accessible account of some of the discipline's guiding principles and methodology with abundant examples and illustrations of anthropologists at work.

Published in 1925, The Gift is one of French sociologist Marcel Mauss's few non-collaborative works. In it, he elevates what might appear to be a simple gift from the status of innocent object to something that has the capacity to motivate people and define social relationships. The Gift analyzes cultures across the world and across time, with the way gifts are given and received working as a guide to understanding the rules and traditions of many different societies.

Western thinking about the Middle and Far East has been distorted by stereotype and inaccuracy. This argument lies at the center of Palestinian-American literary theorist Edward Said's groundbreaking book, Orientalism. Originally published in 1978, it cemented Said's reputation as the father of postcolonial studies.

First published in 1651, Leviathan drove important discussions about where kings get their authority to rule and what those kings must, in turn, do for their people. This is known as the "social contract". Thomas Hobbes wrote the book while exiled from his native England following the English Civil War that unseated King Charles I. In the face of England's radical - if temporary - rejection of its monarchy, Hobbes wanted to explain why it was important to have a strong central government, which in his time meant having a sovereign at its head.

The year is 1919. The horror of the First World War is fresh for the protagonists of Time of the Magicians, each of whom finds himself at a crucial juncture. Benjamin is trying to flee his overbearing father and floundering in his academic career, living hand to mouth as a critic. Wittgenstein, by contrast, has dramatically decided to divest himself of the monumental fortune he stands to inherit, in search of spiritual clarity.

What is the nature of our personal relationship with God? That's the core question of Fear and Trembling. If God asks us to do something we instinctively feel is unethical, must we obey and have faith that he knows best? Examining this question, Danish philosopher Kierkegaard considers the biblical story in which God commands Abraham to sacrifice his only son, Isaac. His unique reading of the story breaks new ground, focusing on our relationship with God at an individual level.

Søren Kierkegaard has long been considered the father of the philosophical movement known as Christian existentialism, which focuses on the living human being. In his major 1849 work, The Sickness unto Death, he takes listeners on a journey from the human self, its spirit, despair and sin, through to faith.

Explaining Postmodernism is intellectual history with a polemical twist, providing fresh insights into the debates underlying the furor over political correctness, multiculturalism, and the future of liberal democracy.

Visionary physicist Geoffrey West is a pioneer in the field of complexity science, the science of emergent systems and networks. The term complexity can be misleading, however, because what makes West's discoveries so beautiful is that he has found an underlying simplicity that unites the seemingly complex and diverse phenomena of living systems, including our bodies, our cities, and our businesses.