First published in 1710, George Berkeley's A Treatise Concerning the Principles of Human Knowledge is a seminal contribution to Empiricist philosophy. Making the bold assertion that the physical world consists only of ideas and thus does not exist outside the mind, this work establishes Berkeley as the founder of the immaterialist school of thought. A major influence on such later philosophers as David Hume and Immanuel Kant, Berkeley's ideas have played a role in such diverse fields as mathematics and metaphysics and continue to spark debate today.

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.

Published in 1748, An Enquiry Concerning Human Understanding is Scottish empiricist philosopher David Hume's distillation of his mature philosophy. Addressing themes including the limits of human understanding, the compatibility of free will with determinism, weaknesses in the foundations of religion, and the appeal of skepticism, An Enquiry Concerning Human Understanding is Hume's attempt to revise and clarify the ideas of his earlier A Treatise of Human Nature.

This Leibniz collection contains some of the philosopher’s most important works and ideas, spans three decades and illuminates the fascinating intellectual journey undertaken by him in his quest for truth. A prodigious polymath, Leibniz was a mathematician, philosopher, physicist and statesman and engaged with a sweeping range of ideas and disciplines, striving throughout his life to be at the cutting edge of scientific thinking. These Principal Essays are arranged in chronological order.

Kant's Prolegomena, although a small book, is without doubt the most important of his writings, writes the translator, Paul Carus. Prolegomena means, literally, prefatory or introductory remarks, and it furnishes us with a key to his main work, The Critique of Pure Reason; in fact, it is an extract containing all the salient ideas of Kant's system. It approaches the subject in the simplest and most direct way and is therefore best adapted as an introduction into his philosophy.

The front cover of the second edition of Language, Truth and Logic carried this statement in capital letters: ‘THE CLASSIC TEXT WHICH FOUNDED LOGICAL POSITIVISM - AND MODERN BRITISH PHILOSOPHY.’ It was a bold statement, but the book, first published in 1936 when A. J. Ayer was just 25 and a lecturer on philosophy at Christ Church, Oxford, drew unstinting praise from leading figures in the field, including Bertrand Russell.

Conjectures and Refutations is one of Karl Popper’s most wide-ranging and popular works, notable not only for its acute insights into the way scientific knowledge grows, but also for applying those insights to politics and to history. It provides one of the clearest and most accessible statements of the fundamental idea that guided his work: not only our knowledge but our aims and our standards grow through an unending process of trial and error.

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

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.

A dialogue between Socrates and Meno probes the subject of ethics. Can goodness be taught? If it can, then we should be able to find teachers capable of instructing others about what is good and bad, right and wrong, or just and unjust.

Socrates is in prison, sentenced to die when the sun sets. In this final conversation, he asks what will become of him once he drinks the poison prescribed for his execution. Socrates and his friends examine several arguments designed to prove that the soul is immortal. This quest leads him to the broader topic of the nature of mind and its connection not only to human existence but also to the cosmos itself. What could be a better way to pass the time between now and the sunset?

Phaedrus lures Socrates outside the walls of Athens, where he seldom goes, by promising to share a new work by his friend and mentor, Lysias, a famous writer of speeches. This dialogue provides a powerful example of the dialectical writing that Plato uses to manifest ideas that are essential to human existence and to living a good life. Phaedrus shows how oral and written forms of language relate to each other and to philosophy.

Rene Descartes is often described as the first modern philosopher, but much of the content of his Meditations on First Philosophy can be found in the medieval period that had already existed for more than a thousand years. Does God exist? If so, what is his nature? Is the human soul immortal? How does it differ from the body? What role do sense experience and pure reason play in knowing?

This recording contains four important and related works by Heidegger: 'What Is Philosophy', 'What Is Metaphysics', 'On the Essence of Truth' and 'The Question of Being'.

Immanuel Kant’s Critique of Pure Reason can lay claim to being the most important single work of modern philosophy, a work whose methodology, if not necessarily always its conclusions, has had a profound influence on almost all subsequent philosophical discourse. In this work Kant addresses, in a groundbreaking elucidation of the nature of reason, the age-old question of philosophy: “How do we know what we know?” and the limits of what it is that we can know with certainty.

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.

The Problems of Philosophy discusses Bertrand Russell's views on philosophy and the problems that arise in the field. Russell's views focus on knowledge rather than the metaphysical realm of philosophy. The Problems with Philosophy revolves around the central question that Russell asks in his opening line of Chapter 1 - Is there any knowledge in the world which is so certain that no reasonable man could doubt it?

Socrates is in prison, sentenced to die when the sun sets. In this final conversation, he asks what will become of him once he drinks the poison prescribed for his execution. Socrates and his friends examine several arguments designed to prove that the soul is immortal. This quest leads him to the broader topic of the nature of mind and its connection not only to human existence but also to the cosmos itself. What could be a better way to pass the time between now and the sunset?

This simplistic and ingenious allegory from one of the fathers of Western philosophy casts light on society’s naiveté and ignorance.

Considered by many to be Hannah Arendt's greatest work, published as she neared the end of her life, The Life of the Mind investigates thought itself, as it exists in contemplative life. In a shift from her previous writings, most of which focus on the world outside the mind, this work was planned as three volumes that would explore the activities of the mind considered by Arendt to be fundamental. What emerged is a rich, challenging analysis of human mental activity, considered in terms of thinking, willing, and judging.

"The central miracle asserted by Christians is the Incarnation. They say that God became Man. Every other miracle prepares the way for this, or results from this." This is the key statement of Miracles, in which C. S. Lewis shows that a Christian must not only accept but rejoice in miracles as a testimony of the unique personal involvement of God in his creation.

Two contrasting reflections by Aristotle which cover very particular ground. In 'On the Soul', Aristotle presents his view of the 'life essence' which, he argues, is possessed by living things whether plants, animals or humans. Not a 'soul' in the generally accepted Western use of the term, this 'soul', he says, is a life force that is indivisible from the organism that possesses it.

There is a cause, or a reason, behind everything that happens. This is the fundamental view behind the classical proposition the Principle of Sufficient Reason, which, in 1813, Schopenhauer chose as his subject for further examination in his doctoral dissertation On the Fourfold Root of the Principle of Sufficient Reason....

Already a classic, this landmark study of early Western thought now appears in a new edition with expanded coverage of the Middle Ages. Author Anthony Gottlieb looks afresh at the writings of the great thinkers, questions much of conventional wisdom, and explains his findings with unbridled brilliance and clarity. From the pre-Socratic philosophers through the celebrated days of Socrates, Plato, and Aristotle, up to Renaissance visionaries like Erasmus and Bacon, philosophy emerges here as a phenomenon unconfined by any one discipline.

The Summa Theologica, by Thomas Aquinas, is a fundamental text in Catholic doctrine, a compendium of theology that has been studied and debated since its first publication in the 13th century. Furthermore, it has been widely regarded as one of the classics of Western philosophy, not least because, perhaps for the first time in such a systematic manner, it set out to consider the views of non-Christian figures such as Aristotle, Boethius, Muslim writers including Averroes (Ibn Rushd) and Avicenna (Ibn Sina) and the Sephardic Jewish scholar Maimonides.

The Varieties of Religious Experience is considered to be the classic work in the field. To quote Wikipedia, "James was most interested in understanding personal religious experience. The importance of James to the psychology of religion - and to psychology more generally - is difficult to overstate. He discussed many essential issues that remain of vital concern today. What makes James writing so special is that he could take a very complex subject and, without watering it down, make it understandable to 'the rest of us.'"

One of the most influential philosophers and theologians in the history of Western thought, St Thomas Aquinas established the foundations for much of modern philosophy of religion, and is famous for his arguments for the existence of God. In this cogent and multifaceted introduction to the great saint's work, Edward Feser argues that you cannot fully understand Aquinas' philosophy without his theology, and vice-versa. He covers Aquinas' thoughts on the soul, natural law, metaphysics, and more.

Despite the recent ferocious public debate about belief, the concept most central to the discussion "God" frequently remains vaguely and obscurely described. Are those engaged in these arguments even talking about the same thing? In a wide-ranging response to this confusion, esteemed scholar David Bentley Hart pursues a clarification of how the word "God” functions in the world’s great theistic faiths.

In The Dream of Enlightenment, Anthony Gottlieb expertly navigates a second great explosion of thought, taking us to northern Europe in the wake of its wars of religion and the rise of Galilean science. In a relatively short period - from the early 1640s to the eve of the French Revolution - Descartes, Hobbes, Spinoza, Locke, Leibniz, and Hume all made their mark. The Dream of Enlightenment tells their story and that of the birth of modern philosophy.

Meditations is former U.S. President Bill Clinton's favorite book. This audio consists of a series of personal writings by Marcus Aurelius, Roman Emperor 161-180 AD, setting forth his ideas on Stoic philosophy.