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.

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.

Published in 1961, the year of Frantz Fanon's death, The Wretched of the Earth is both a powerful analysis of the psychological effects of colonization and a rallying cry for violent uprising and independence. The book rejects colonial assumptions that the people of colonized countries need to be guided by their European colonizers because they are somehow less evolved or civilized. Fanon argues that violence is justified to purge colonialism not just from the countries themselves, but from the very souls of their inhabitants.

Throughout the twentieth century, The Protestant Ethic and the Spirit of Capitalism was regarded as an important sociological and economic text, continuing into the twenty-first century, when extreme capitalism has continued to come under fire. Weber's work provided a history, from where the profit motive could be ethically justified. Max Weber combined his interests in sociology, political economy and history to give perspective to his analysis. Concentrating principally on the experience of the West, he returned to the time when religion, its concepts and practice, dominated society.

Friedman did not just demonstrate that monetary policy plays a vital role in broader economic stability. He also argued that economists got their monetary policy wrong in the 1950s and 1960s by misunderstanding the relationship between inflation and unemployment. In Friedman's view, previous generations of economists had no justification for believing that governments could permanently decrease unemployment by allowing inflation - and vice versa.

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.

Issues of human rights and freedoms always inflame passions, and John Rawls's A Theory of Justice will do the same. Published in 1971, it links the idea of social justice to a basic sense of fairness that recognizes human rights and freedoms. Controversially, though, it also accepts differences in the distribution of goods and services - as long as they benefit the worst off in society.

According to Aristotle, the ultimate human good is eudaimonia, an ancient Greek word that can be translated as happiness, or flourishing. Eudaimonia comes from a life of virtuous (or good) action. Virtues such as justice, restraint, and practical wisdom cannot simply be taught - they must be developed over time by cultivating virtuous habits. The making of virtuous choices can be developed by using practical wisdom and by recognizing the desirable middle ground between extremes of human behavior.

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.

When American sociologist C. Wright Mills's The Sociological Imagination was first published in 1959, it provoked much hostile reaction. This was understandable: the book was a hard-hitting attack on how sociology was practiced - and on a number of leading sociologists. Mills was a fierce critic of both modern capitalism and Soviet-style authoritarianism, and argued that the sociology profession failed to look at how people's problems are connected to the structures of the society in which they live.

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.

Frantz Fanon's Black Skin, White Masks offers a radical analysis of the psychological effects of colonization on the colonized. Born in 1925 on the island of Martinique - at the time a French colony - Fanon witnessed firsthand the abuses of white colonizers and the system's effects on his country. His revulsion was only confirmed later in life when he worked as a psychiatrist in Algeria, another French colony. Fanon's work played a pivotal role in the civil rights movements of the 1960s and was later taken up by scholars of postcolonialist 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.

Why do we want to justify our decisions, even if they appear to be irrational? The answer lies in cognitive dissonance, the mental discomfort we experience when we hold two contradictory beliefs at the same time. In A Theory of Cognitive Dissonance, first published in 1957, American social psychologist Leon Festinger investigates the problem. Festinger puts forward the idea that we have developed mechanisms to try to deal with the stress brought on by cognitive dissonance.