The leviathan is the vast unity of the State. But how are unity, peace, and security to be attained? Hobbes’ answer is sovereignty, but the resurgence of interest today in Leviathan is due less to its answers than its methods: Hobbes sees politics as a science capable of the same axiomatic approach as geometry.

John Locke and his works - particularly An Essay Concerning Human Understanding - are regularly and rightly presented as foundations for the Age of Enlightenment. His primary epistemological message - that the mind at birth is a blank sheet waiting to be filled by the experiences of the senses - complemented his primary political message: that human beings are free and equal and have the right to envision, create and direct the governments that rule them and the societies within which they live.

Often considered the foundation of political liberalism, John Locke's Two Treatises of Government was first published anonymously in 1689, in the wake of England's Glorious Revolution. In The First Treatise of Government, Locke refutes the idea of divine monarchy, while The Second Treatise of Government articulates Locke's philosophy of government, which he based upon his theories of natural rights and the social contract.

The title Politics literally means ‘the things concerning the city’. Here, Aristotle considers the important role that politics plays in the life of the community and its contribution to harmonious and virtuous existence. It is divided into eight books and was a cornerstone in political philosophy for centuries despite certain features - including attitudes towards slaves and women - clearly placing its conclusions and advice within the confines of Athenian society of the fourth century BCE.

Plutarch (c. AD 46-AD 120) was born to a prominent family in the small Greek town of Chaeronea, about 20 miles east of Delphi in the region known as Boeotia. His best known work is the Parallel Lives, a series of biographies of famous Greeks and Romans, arranged in pairs to illuminate their common moral virtues and vices. The surviving lives contain 23 pairs, each with one Greek life and one Roman life as well as four unpaired single lives.

John Stuart Mill (1808-1873) was a torchbearer for liberal thought in the 19th century, including liberty of the individual and freedom of speech, and he championed women's suffrage in Parliament. A remarkable man - he learned Greek aged three and at eight had read Herodotus, Xenophon and Plato - he campaigned all his life for a just society. These two essays are his key works.

Published in 1762, it had a profound impact on the approach to the education and upbringing of a child, through infancy, childhood, adolescence and into adulthood. This was partly fuelled by the format – for Rousseau presents before us the boy Emile, taking him through the various stages of life, and as Emile becomes a young man, introducing a female counterpart, Sophie. This device personalises what would otherwise be a more formal philosophical presentation.

Perhaps one of the most revolutionary works of philosophy ever presented, The Phenomenology of Spirit is Hegel's 1807 work that is in numerous ways extraordinary. A myriad of topics are discussed, and explained in such a harmoniously complex way that the method has been termed Hegelian dialectic. Ultimately, the work as a whole is a remarkable study of the mind's growth from its direct awareness to scientific philosophy, proving to be a difficult yet highly influential and enduring work.

The foundation for all modern economic thought and political economy, The Wealth of Nations is the magnum opus of Scottish economist Adam Smith, who introduces the world to the very idea of economics and capitalism in the modern sense of the words.

Elements of The Philosophy of Right, a key work in the output of Georg Wilhelm Hegel (1770-1831), appeared in 1820 - and was arguably his last major publication. His intention was to state his views on the philosophy of law, political and social theory and ethics. Appearing as it did in a crucial time for the Prussian state - still affected by the Napoleonic wars and their aftermath - it was viewed differently by those on both the left and the right of the political spectrum.

On War was first published in 1832, at a time when muskets and cavalry were a dominating presence on the battlefield. Yet in the 21st century it remains a much-read and studied treatise on the subject – perhaps the most important European classic of its kind – and this despite the author’s demise before he could finish what was an extended review of the whole subject of military strategy. Why is that?

Published four years after Rousseau's death, Confessions is a remarkably frank and honest self-portrait, described by Rousseau as "the history of my soul". From his idyllic youth in the Swiss mountains, to his career as a composer in Paris and his abandonment of his children, Rousseau lays bare his entire life with preternatural honesty.

In a career spanning 60 years, Sir Karl Popper has made some of the most important contributions to the 20th century discussion of science and rationality. The Myth of the Framework is a collection of some of Popper's most important material on this subject.

The Theory of Moral Sentiments (1759) was the first major text by Adam Smith who, seven years later, was to publish what was to become one of the major economic classics, The Wealth of Nations (1776). However, Smith regarded The Theory of Moral Sentiments as his most important work because in it he identified the profound human instinct to act not necessarily in self-interest but through, as he phrased it, a ‘mutual sympathy of sentiments’.

Aristotle’s Nicomachean Ethics and Eudemian Ethics represent, in many ways, the Western classical springboard for the systematic study and implementation of ethics, the optimum behaviour of the individual. (By contrast, Aristotle’s Politics concerns the optimum blueprint for the city-state.) It is in the hands of each individual, he argues in these books on personal ethics, to develop a character which bases a life on virtue, with positive but moderate habits.

John Locke and his works - particularly An Essay Concerning Human Understanding - are regularly and rightly presented as foundations for the Age of Enlightenment. His primary epistemological message - that the mind at birth is a blank sheet waiting to be filled by the experiences of the senses - complemented his primary political message: that human beings are free and equal and have the right to envision, create and direct the governments that rule them and the societies within which they live.

John Locke (1632-1704) was a product of his troubled times: he lived through the English Civil War, the Interregnum, the Restoration, Monmouth’s Rebellion, the Bloody Assizes and the Glorious Revolution. His empirical thinking was very much directed at finding rational solutions to the root causes of those troubles.

Critique of Judgement was published in 1790 and is divided into two parts, the Critique of Aesthetic Judgement and the Critique of Teleological Judgement. Our ‘judgements of taste’, as Kant describes our aesthetic judgements, have both a personal and a universal function: personal, because we have a subjective aesthetic response to the ‘agreeable’, the ‘beautiful’, the ‘sublime’ and the ‘good’; but also there is a ‘universal’ aspect because our aesthetic response has a ’disinterested’ element. This brings under Kant’s spotlight, for example, the concept of beauty and the perception of beauty.

Though it first aroused anger and controversy rather than admiration and acceptance, A Theologico-Political Treatise was a landmark in the analysis of theology (with particular reference to the Bible and its Jewish and Christian interpretations) and its relationship to philosophy and politics. Spinoza’s scholarly analysis, based on careful study, demonstrated that the Bible was composed by many writers over the centuries - and that even the Pentateuch, the first five books, were not the work of Moses, as was generally assumed at the time.

As philosophy professor Taylor Carman explains in his helpful introduction, Edmund Husserl (1859-1938) was the founder of modern phenomenology, one of the most important and influential movements of the 20th century. Ideas, published in 1913 – its full title is Ideas for a Pure Phenomenology and Phenomenological Philosophy – was the key work. It is arguably ‘the most fundamental and comprehensive statement of the fundamental principles of Husserl’s mature philosophy’.

The leviathan is the vast unity of the State. But how are unity, peace, and security to be attained? Hobbes’ answer is sovereignty, but the resurgence of interest today in Leviathan is due less to its answers than its methods: Hobbes sees politics as a science capable of the same axiomatic approach as geometry.

Poetics and Rhetoric are the two major works by Aristotle which, after more than 2,000 years, remain key behavioural handbooks for anyone interested in story, performance, presentation and indeed psychology. The continuing influence of Poetics, for example, is readily discernible even among the scriptwriters of Hollywood!

In 1929, Martin Heidegger (1889-1976) published his remarkable book Kant and the Problem of Metaphysics. The Kantbuch, as Heidegger often called it, is regarded by many as a vital supplement to the unfinished second part of Heidegger’s most influential work, Being and Time, which was published two years earlier in 1927.

Karl Popper's THE POVERTY OF HISTORICISM is one of the most important books on the social sciences to have appeared since the Second World War. It is also the work of one of the most original thinkers of the twentieth century, and a devastating criticism of the idea that there are laws of development in history and that human beings are able to discover them. Popper dedicated the book to all those who fell victim to the fascist and communist belief in Inexorable Laws of Historical Destiny

The four books of the Summa contra Gentiles were written by Thomas Aquinas between 1259-1265, before the considerably larger and more influential, Summa Theologica. The purpose of each work was different. Whereas the Summa Theologica addressed the faithful, especially theology students, the intention of the Summa Contra Gentiles (Systematic Exposition Against Non-Christians) was to speak to a non-aligned and even hostile audience. To that purpose, Aquinas presented arguments ‘refuting specific beliefs or heresies.'

Aristotle's Metaphysics was the first major study of the subject of metaphysics - in other words, an inquiry into 'first philosophy', or 'wisdom'. It differs from Physics which is concerned with the natural world: things which are subject to the laws of nature, things that move and change, are measurable. In Metaphysics, the study falls on 'being qua being' - being insofar as it is being; the causes and principles of being, the causes and principles of substances.

Demosthenes (384-322 BCE) is regarded as one of the greatest orators of Classical times. This view has persisted through the centuries even though his rousing speeches warning of the dangers of Macedonian expansion failed to stem the course of continued military success. Each of the orations in this collection is preceded with an introduction setting the scene, and outlining the context in which they were delivered. This also gives a concise picture of Athens at this difficult point in its history. All the speeches are prefaced by the historical setting.

The Economic Consequences of the Peace (1919) was one of the most important documents to come out of World War I – specifically the period of the Armistice and the subsequent settlement negotiations. And, a century on, it remains of particular relevance to our times – an uncompromising and forthright analysis of how international diplomacy can be suffused by personalities, prejudices, personal ambition and outright, uncontrolled feelings of revenge.

Aristotle considers ‘the principles and causes of change, or movement’ behind both animate and inanimate things. It is philosophy, not science, but over centuries affected the views of those involved in the ‘natural sciences’. The text emerged from the Lyceum, the school founded by Aristotle, and is accepted to be a compilation of texts, some of which - but perhaps not all - is by Aristotle. Regardless of authorship, its importance is unquestioned.

The Critique of Practical Reason was published in 1788, seven years after Immanuel Kant's major work, Critique of Pure Reason. In it, Kant sets out his moral philosophy - and it proved a seminal text in the history of the subject. He argues that the summum bonum (the highest good) of life is that rather than just pursuing happiness, people should inhabit a moral dimension that enables them to deserve the happiness that God can give. Though much shorter than Critique of Pure Reason, this is the sourcebook for Kant’s ethical doctrines.