As intriguing today as when it was first published, Hume's An Enquiry Concerning Human Understanding is a fascinating exploration into the nature of human knowledge. Using billiard balls, candles, and other colorful examples, Hume conveys the core of his empiricism - that true knowledge can be gained only through sensory experience.

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.

Born out of the political turmoil of the English Civil War, Leviathan stands out as one of the most in influential political and philosophical texts of the 17th century. It argues for the restoration of the monarchy in light of the republic and calls for a commonwealth ruled by an authoritative, autocratic figure with absolute sovereignty. This would put an end to all controversy, war, and fear and establish peace via social contract.

Rousseau's Social Contract remains, after a quarter of a millennium, one of the most controversial texts in the history of political philosophy, variously seen as a model for participatory democracy, a blueprint for totalitarianism, and several points in between. In addition to Rousseau’s magnum opus, this production includes an introduction by George Douglas Howard Cole, an English political theorist, economist, writer and historian. Also included are three discourses that Rousseau composed apart from The Social Contract.

Benedict de Spinoza's Ethics, first published in 1677, constitutes a major systematic critique of the traditional and religious foundations of philosophical thought. In it, Spinoza follows a logical step-by-step format consisting of definitions, axioms, propositions, proofs, and corollaries to create a comprehensive inquiry into the truth about God, nature, and humans' place within the universe. From these broad metaphysical themes, Spinoza derives what he considered to be the highest principles of religion and society and lays out an ethical system in which reason is the supreme value.

Aristotle's most complicated and academic work. This is a challenging work for even those who admire his other seven books. Incomparable analysis in language and thought, with a clear, succinct prose touch.

Two years before he died, St. Thomas Aquinas, probably the greatest teacher the Church has ever known, was asked by his assistant Brother Reginald to write a simple summary of the faith of the Catholic Church for those who lacked the time or the stamina to tackle his massive Summa Theologica. In response, the great saint quickly set down in language that non-scholars can understand his peerless insights into the major topics of theology: the Trinity, Divine Providence, the Incarnation of Christ, the Last Judgment, and much more.

The Fable of the Bees—a satirical poem, prose discussion, three essays and six dialogues completed in 1729—exposes human vices but defends them as a necessity within a wealthy society. Mandeville’s bees thrive until they start living by honesty and virtue… then they are impoverished. Mandeville did not play by the rules: he satirized the sins of society but also ridiculed the widespread hypocrisy of deploring these sins whilst reaping their benefits. He and his work were attacked for the rest of the century.

The Prince is a treatise that systematically charts the best strategies for successful governing. It unapologetically places realism above idealism, showing would-be kings how to get what they want while appearing to be generous and honourable, and advocates that the means — cruelty, duplicity and horror —justify the ends of secure monarchical rule. But it can also be read as the work of a secret republican subtly undermining the despotism of the ruling Medici family.

After more than 2,300 years, the Greek philosopher Aristotle still remains one of the most influential thinkers who has ever lived. There was hardly any field of human knowledge in existence during his day in which he did not make a major contribution. Additionally, he probed areas which were never before examined. Indeed, one could make the claim that no individual person has ever known as much about this world as Aristotle. His analyses of zoology and logic paved the way for modern forensic techniques, and for which every scientist down to this day owes him a debt of gratitude.