Philosophy is a field of study that includes diverse subfields such as aesthetics, epistemology, ethics, logic, and metaphysics, in which people ask questions such as whether God exists, whether knowledge is possible, and what makes actions right or wrong. The fundamental method of philosophy is the use of reasoning to evaluate arguments concerning these questions. However, the exact scope and methodology of philosophy is not rigid. What counts as philosophy is itself debated, and it varies across philosophical traditions.
The term philosophy comes from the Greek word "Φιλοσοφία" (philo-sophia), which means "love of wisdom". The term is notoriously difficult to define (see definition of philosophy) because of the diverse range of ideas that have been labeled as a philosophy. The Penguin Dictionary of Philosophy defines it as the study of "the most fundamental and general concepts and principles involved in thought, action, and reality". The Penguin Encyclopedia says that philosophy differs from science in that philosophy's questions cannot be answered empirically, and from religion in that philosophy allows no place for faith or revelation. However, these points are called into question by the Oxford Dictionary of Philosophy, which states: "the late 20th-century... prefers to see philosophical reflection as continuous with the best practice of any field of intellectual enquiry." Indeed, many of the speculations of early philosophers in the field of natural philosophy eventually formed the basis for modern scientific explanations on a variety of subjects.
Branches of philosophy
There is no universal agreement about which subjects are the main branches of philosophy. In The Story of Philosophy, Will Durant lists logic, epistemology, ethics, aesthetics, and metaphysics, but there are many places where these subjects overlap, and many philosophical ideas that cannot be neatly put into one of these categories.
Each branch has its own particular questions. Logic asks: How do we distinguish arguments from premises to conclusions as valid or invalid? Epistemology asks: Is knowledge possible? How do we know what we know? Ethics asks: Is there a difference between morally right and wrong actions, values, or institutions? Which actions are right and which are wrong? Are values absolute or relative? How is it best to live? Is there a normative value on which all other values depend? Are values 'in' the world (like tables and chairs) and if not, how should we understand their ontological status? Aesthetics asks: What is beauty? And metaphysics asks: What is reality? What exists? Do things exist independently of perception?
Outside these five broad categories are other areas of philosophical inquiry. Politics (seen by Aristotle as an extension of ethics), physics (in the sense of the nature of matter and energy), and religion are all fields considered by philosophers.
History of philosophy
The history of Western philosophy is traditionally divided into three eras: Ancient philosophy, Medieval philosophy, and Modern philosophy. Some philosophers have argued that human civilization has passed into a new, "post-modern" period. Others believe that there is a distinction between the Modern philosophy and Contemporary philosophy, but there is great disagreement about the content of this difference. Eastern philosophy was, for most of its history, independent of Western philosophy.
Ancient Greek and Roman philosophy
Ancient Greek philosophy is typically divided into the pre-Socratic Period, the Socratic period, and the post-Aristotelian period. The pre-Socratic period was characterized by metaphysical speculation, often preserved in the form of grand, sweeping statements, such as "All is fire", or "All changes". Important pre-Socratic philosophers include Thales, Anaximander, Anaximenes, Democritus, Parmenides, and Heraclitus. The Socratic period is named in honor of the most recognizable figure in Western philosophy, Socrates, who, along with his pupil Plato, revolutionized philosophy through the use of the Socratic method, which developed the very general philosophical methods of definition, analysis, and synthesis. While Socrates wrote nothing himself, his influence as a "skeptic" survives through Plato's works. Plato's writings are often considered basic texts in philosophy as they defined the fundamental issues of philosophy for future generations. These issues and others were taken up by Aristotle, who studied at Plato's school, the Academy, and who often disagreed with the writings of Plato. The post-Aristotelian period ushered in such philosophers as Euclid, Epicurus, Pyrrho, and Sextus Empiricus. A woman philosopher of the Ancient period is Hipparchia the Cynic, who flourished around 300 B.C.
The medieval period of philosophy came with the collapse of Roman civilization and the dawn of Christianity, Islam, and rabbinic Judaism. The medieval period brought Christian scholastic philosophy, with writers such as Augustine of Hippo, Boethius, Anselm, Robert Grosseteste, Albertus Magnus, Roger Bacon, Bonaventure, Thomas Aquinas, John Duns Scotus, William of Ockham, Nicholas of Cusa, and Francisco Suárez. A female Christian philosopher of the period was a student of Abelard named Heloise. The philosophers in the scholastic Christian tradition and philosophers in the other major Abrahamic religions, such as the Jewish philosophers Saadia Gaon and Maimonides, and the Muslim philosophers Avicenna, Al-Ghazali, and Averroes, were intercommunicative. These religious traditions took on questions about the relation of man to God. The philosophy of this period is characterized by analysis of the nature and properties of God; the metaphysics involving substance, essences and accidents (that is, qualities that are respectively essential to substances possessing them or merely happening to be possessed by them), form, and divisibility; and logic and the philosophy of language.
Many of these philosophers took as their starting point the theories of Plato or Aristotle. Others, however, such as Tertullian, rejected Greek philosophy as antithetical to revelation and faith.
Modern Western philosophy
Modern philosophy is generally considered to begin with the work of René Descartes, but his work was greatly influenced by the questioning of his correspondent, Princess Elizabeth of Bohemia, who posed the mind-body problem to Descartes.
Medieval philosophy had been concerned primarily with argument from authority, and the analysis of ancient texts using Aristotelian logic. The Renaissance saw an outpouring of new ideas that questioned authority. Roger Bacon (1214-1294?) was one of the first writers to advocate putting authority to the test of experiment and reason. Niccolò Machiavelli (1469-1527) challenged conventional ideas about morality. Francis Bacon (1561-1626) wrote in favor of the methods of science in philosophical discovery.
Analytic and Continental
The late modern period in philosophy, beginning in the late nineteenth century and lasting to the 1950s, was marked by a developing schism between the "Continental" tradition and the "Analytic" tradition associated with English-speaking countries.
The two traditions appear radically different, yet they have a common root. Both reject the Cartesian and empiricist traditions that had dominated philosophy since the early modern period, and both also reject the "obsession with psychological explanation" that pervaded the logic and method of idealist philosophy.
What underlies the Analytic tradition is the view (originally defended by Ockham) that philosophical error arises from misunderstandings generated by language. We imagine that to every word (e.g. baldness, existence) there corresponds something in reality. According to analytic philosophers, the true meaning of ordinary sentences is "concealed by their grammatical form", and we must translate them into their true form (understood as their logical form) in order to clarify them. The difficulty, so far unresolved, is to determine what the correct logical form must be. Some philosophers (beginning with Frege and Bertrand Russell) have argued that first order logic shows us the true logical form of ordinary sentences.
"Continental" philosophy, in the hands of the phenomenologists such as Edmund Husserl and Maurice Merleau-Ponty, took a different turn in its preoccupation with consciousness. A fundamental assumption of this school is that mental phenomena must have intentionality: they have objects external to, and independent of, the mind itself. Thus an important theme of phenomenology is an attack on the subject-object dualism of Cartesianism.
Yet this intentionality is an assumption shared by analytic philosophers. A similar idea (though developed from a somewhat different starting point) is the view known as externalism, defended recently by philosophers such as John McDowell and Gareth Evans. Externalism posits that proper names (Socrates, George Bush) refer directly to their bearers, and that their meaning is not mediated by any "sense" or subjective meaning. Thus the thought "Socrates is wise" has Socrates himself as a component. It follows that here can be no question of our being radically mistaken as to the nature or existence of an external world; such a mistake would literally make no sense. If the question of whether the Eiffel Tower or London existed were intelligible, we would have to admit the possibility that those names have no meaning, and thus that the question was not intelligible in the first place. This is strikingly similar to themes considered by "Continental" writers such as Heidegger, who argued that the "scandal of philosophy" is not that the proof of the existence of an external world has yet to be given, "but that such proofs are expected and attempted again and again". To have faith in the reality of the "external world" presupposes a subject which is worldless. But we are embedded in the world.
Other philosophical traditions
Many societies have considered philosophical questions and built philosophical traditions based upon each other's works. Eastern and Middle Eastern philosophical traditions have influenced Western philosophers. Russian, Jewish, Islamic and recently Latin American philosophical traditions have contributed to, or been influenced by, Western philosophy, yet each has retained a distinctive identity.
The differences between traditions are often based on their favored historical philosophers, and varying stress on ideas, procedural styles, or written language. The subject matter and dialogues of each can be studied using methods derived from the others, and there are significant commonalities and exchanges between them.
The origins of Hindu philosophy are to be traced in Vedic speculations (circa 1500 BCE) about the universe and Rta - universal order. Other major texts with philosophical implications include the Upanishads and the Bhagavad Gita, from circa 1000 BCE to 500 BCE. At about the same time, the shramana schools, including Jainism and Buddhism, developed.
In Persia, Zarathustra's teachings, which were a new basis for the Iranian branch of Indo-Iranian philosophy, appeared around 900 BCE.
In nineteenth century South India, there developed Ayyavazhi which applies a common formula of creationism on Human beings and the Universe. This philosophy is based on the teachings of Ayya Vaikundar.
Other philosophical traditions, such as African, are rarely considered by foreign academia. Since emphasis is mainly placed on western philosophy as a reference point, the study, preservation and dissemination of valuable, but relatively unknown, non-Western philosophical works face many obstacles.
Metaphysics and epistemology
Rationalism and empiricism
René Descartes, who is often called the father of modern philosophy, proposed that philosophy should begin with a radical skepticism about the possibility of obtaining reliable knowledge. In 1641, in Meditations on First Philosophy, he used this method of doubt in an attempt to establish what knowledge is most certain. He chose as the foundation of his philosophy the famous statement Cogito ergo sum ("I think, therefore I am"). He then attempted to rebuild a system of knowledge based on this single supposedly indubitable fact. His approach became known as rationalism; it attracted such philosophers as Baruch Spinoza, Gottfried Leibniz, and Christian Wolff.
In response to the popularity of rationalism, John Locke wrote An Essay Concerning Human Understanding in 1689, developing a form of naturalism and empiricism on roughly scientific principles. Hume's work A Treatise of Human Nature (1739-40) combined empiricism with a spirit of skepticism. Other philosophers who made major contributions to empiricism include Thomas Hobbes and George Berkeley (Bishop Berkeley).
During this era, religious ideas played a mixed role in the struggles that preoccupied secular philosophy. Bishop Berkeley's famous idealist refutation of Isaac Newton is a case of an Enlightenment philosopher who drew substantially from religious ideas. Other influential religious thinkers of the time include Blaise Pascal, Joseph Butler, and Jonathan Edwards. Other major writers, such as Jean-Jacques Rousseau and Edmund Burke, took a slightly different path. The restricted interests of many of the philosophers of the time foreshadow the separation and specialization of different areas of philosophy that would occur in the twentieth century.
Kantian philosophy and the rise of idealism
Immanuel Kant wrote his Critique of Pure Reason (1781/1787) in an attempt to reconcile the conflicting approaches of rationalism and empiricism and establish a new groundwork for studying metaphysics. Kant's intention with this work was to look at what we know and then consider what must be true about the way we know it. One major theme was that there are fundamental features of reality that escape our direct knowledge because of the natural limits of the human faculties. Kant's method was modeled on Euclid, though he eventually acknowledged that pure reason was insufficient to discover all truth. Kant's work was continued in the work of Johann Gottlieb Fichte, Friedrich Schelling, and Arthur Schopenhauer.
Kant's philosophy, known as transcendental idealism, would later be made more abstract and more general, in the movement known as German idealism, a type of absolute idealism. German idealism rose to popularity with G. W. F. Hegel's publication in 1807 of Phenomenology of Spirit. In that work, Hegel asserts that the aim of philosophy is to spot the contradictions apparent in human experience (which arise, for instance, out of the recognition of the self as both an active, subjective witness and a passive object in the world) and to get rid of these contradictions by making them compatible. Hegel wrote that every thesis creates its own antithesis, and that out of the two arises a synthesis a process known as the "Hegelian dialectic". Philosophers in the Hegelian tradition include Ludwig Andreas Feuerbach and Karl Marx.
The late nineteenth century brought about the rise of a new philosophy in the New World. Charles Peirce and William James are considered to be the co-founders of loosely allied schools of pragmatism, which introduced what would later be called instrumentalism, the idea that what is important for a good theory is how useful it is, not how well it represents reality. Thinkers in this tradition included John Dewey, George Santayana, and C. I. Lewis. Though not widely recognized under the term "pragmatist", philosophers like Henri Bergson and G. E. Moore shared many of the same foundational assumptions with the pragmatists. Pragmatism has recently been taken in new directions by Richard Rorty and Hilary Putnam.
The prominence of logic
With the publication of Bertrand Russell and Alfred North Whitehead's Principia Mathematica in 1910-1913, mathematical logic attracted the interest of many philosophers. With this increased interest in mathematical logic came the rise in popularity for the view known as logical positivism and related theories, all of which shared a commitment to the reliability of empirical tests. Philosophers such as Rudolf Carnap and Hans Reichenbach considered only confirmable or falsifiable claims to be genuine philosophy; anything that could not be deduced from testable claims was considered mere superstition or dogma.
Phenomenology and hermeneutics
At the same time that logic was coming to prominence in America and Britain, a separate movement occurred in continental Europe. Under the influence of Franz Brentano, Edmund Husserl developed a new method to study human problems in his Logical Investigations (1901) and Ideas (1913). The method, known as phenomenology, was used to examine the details of human experience and consciousness in order to observe the most basic facts of human existence; the examination included not just observations of the way the world appears but observations of one's own thoughts, and when and how they occur. This method was developed further in the work of Martin Heidegger and Maurice Merleau-Ponty.
Heidegger expanded the study of phenomenology to elaborate a philosophical hermeneutics. Hermeneutics is a method of interpreting texts by drawing out the meaning of the text in the context it was written in. Heidegger stressed two new elements of philosophical hermeneutics: that the reader brings out the meaning of the text in the present, and that the tools of hermeneutics can be used to interpret more than just texts (e.g. "social text"). Elaborations of philosophical hermeneutics later came from Hans-Georg Gadamer and Paul Ricoeur.
In the mid-twentieth century, existentialism, a popular philosophy that had its roots in the 19th century works of Søren Kierkegaard and Friedrich Nietzsche, developed in Europe, particularly in France and Germany. Kierkegaard, a Danish philosopher generally considered the "Father of Existentialism", argued that "truth is subjectivity", meaning that what is most important to an existing being are questions dealing with an individual's inner relationship to existence. Objective truths (e.g. mathematical truths) are important, but detached or observational modes of thought can never truly comprehend human experience. Nietzsche argued that human existence is the "will to power", a desire for excellence or greatness. Great individuals invent their own values and create the very terms under which they excel. Kierkegaard's knight of faith and Nietzsche's Übermensch are examples of those who define the nature of their own existence.
Drawing on these ideas, existentialism rejects the notion of a human essence, instead trying to draw out the ability of each person to live authentically, which is to say that each person is able to define and determine his or her own life. The most prominent exponent of existentialism is Jean-Paul Sartre, particularly his expression of existentialism in Being and Nothingness (1943). Other influential existentialists include Albert Camus, Simone de Beauvoir, and Karl Jaspers.
The Analytic tradition
The mid-twentieth century, for America and Britain, was not as united behind a major philosophical idea as it had been in the past, but a general philosophical method can be abstracted from the philosophy that was going on at the time. In 1921, Ludwig Wittgenstein published his Tractatus Logico-Philosophicus, which gave a rigidly logical account of linguistic and philosophical issues. Years later he would reverse a number of his positions set out in the Tractatus, as revealed by the content of his second major work, Philosophical Investigations. Investigations encouraged the development of "ordinary language philosophy", which was developed by Gilbert Ryle and a few others. The "ordinary language philosophy" thinkers shared a common outlook with many older philosophers (Jeremy Bentham, Ralph Waldo Emerson, and John Stuart Mill), and it was the philosophical inquiry that characterized English-language philosophy for the second half of the twentieth century.
The implied outlook for "ordinary language philosophy" is that problems in one area of philosophy can be solved independently of problems in other areas of philosophy. Philosophy is thus not a unified whole but a set of unrelated problems. Great thinkers whose work indicates an acceptance of this general outlook include Albert Einstein, Sigmund Freud, P. F. Strawson, Donald Davidson, Hilary Putnam, John Rawls, Noam Chomsky, and the continental thinker Mikhail Bakhtin.
Since then, a plurality of new movements have passed through English-language philosophy. Drawing on the metaphilosophical observation made by Wittgenstein in his second major work, Philosophical Investigations (1953), in which he notes that a good approach to philosophy must itself be based on a careful examination of the meaning of language, a new group of philosophers have adopted a methodological skepticism. This is seen most prominently in the work of W. V. O. Quine and Wilfrid Sellars (but with ideas going back to Auguste Comte and Whitehead). The group's concerns converge on the ideas of naturalism, holism (in opposition to most of what is considered analytic philosophy), instrumentalism, and the denial of Platonic universals. A number of other perspectives have branched out from Wittgenstein's legacy, however.
Ethics and political philosophy
Human nature and political legitimacy
From ancient times, and well beyond them, the roots of justification for political authority were inescapably tied to outlooks on human nature. Plato declared that the ideal society would be run by an oligarchy of philosopher-kings, since those best at philosophy are best able to realize the good. Even Plato, however, required philosophers to make their way in the world for many years before beginning their rule at the age of fifty. For Aristotle, humans are social animals, and communities are set up in order to pursue good for the collective. Aristotle reasoned that, since the state was the highest form of community, it has the purpose of pursuing the highest good. Aristotle understood political power to be the result of natural inequalities in skill and virtue. Because of these differences, he favored an aristocracy of the able and virtuous.
Two millennia later, Thomas Hobbes contested many elements of this view. For Hobbes, human nature is essentially anti-social: people are essentially egoistic, and this egoism makes life difficult in the natural state of things. Moreover, Hobbes argued, though people may have natural inequalities, these are trivial, since no particular talents or virtues that a person may have will make them safe from harm inflicted by others. For these reasons, Hobbes concluded that the state arises from common agreement to raise the community out of the state of nature. This can only be done by the establishment of a sovereign, which (or who) is vested with complete control over the community, and is able to inspire awe and terror in its subjects.
Many in the Enlightenment were unsatisfied with existing doctrines in political philosophy, which seemed to marginalize or neglect the possibility of a democratic state. One attempt to overturn these doctrines was that of Jean-Jacques Rousseau, who responded to Hobbes by claiming that a human is by nature a kind of "noble savage", and that society and social contracts corrupt this nature. In his Second Treatise on Government John Locke agreed with Hobbes that the nation-state was an efficient tool for raising humanity out of a deplorable state, but argued that the sovereign may become an abominable institution compared to the relatively benign unmodulated state of nature.
Following the doctrine of the fact-value distinction, due in part to the influence of David Hume, appeals to human nature for political justification were weakened. Nevertheless, many political philosophers, especially moral realists, still make use of some essential human nature as a basis for their arguments.
Consequentialism, deontology, and the aretaic turn
Jeremy Bentham and John Stuart Mill are famous for propagating utilitarianism, which is the idea that the fundamental moral rule is to strive toward the "greatest happiness for the greatest number". However, in promoting this idea they also necessarily promoted the broader doctrine of consequentialism: that is to say, the idea that the morally right thing to do in any situation is determined by the consequences of the actions under consideration.
In contrast to consequentialism, Immanuel Kant argued that moral principles were simply products of reason. Kant believed that the incorporation of consequences into moral deliberation was a deep mistake, since it would deny the necessity of practical maxims to the working of the will. According to Kant, reason requires that we conform our actions to the categorical imperative, which is an absolute duty. An important 20th-century deontologist, W.D. Ross, argued for weaker forms of duties called prima facie duties.
More recent works have emphasized the role of character in ethics, a movement known as the aretaic turn. One strain of this movement followed the work of Bernard Williams. Williams noted that rigid forms of both consequentialism and deontology demanded that people behave impartially. This, Williams argued, requires that people abandon their personal projects, and hence their personal integrity, in order to be considered moral.
G.E.M. Anscombe, in an influential paper, "Modern Moral Philosophy" (1958), revived virtue ethics, inspired by Aristotle's ethics, as an alternative to what was seen as the entrenched positions of Kantianism and consequentialism. Virtue ethics has since gained some adherence and has been defended by such philosophers as Philippa Foot, Alasdair MacIntyre and Rosalind Hursthouse.
Though often seen as a wholly abstract field, philosophy is not without practical applications. The most obvious applications are those in ethics – applied ethics in particular – and in political philosophy. The political philosophies of Confucius, Kautilya, Sun Zi, Immanuel Kant, John Locke, Thomas Hobbes, Niccolò Machiavelli, Jean-Jacques Rousseau, Karl Marx, John Stuart Mill, Mahatma Gandhi, Robert Nozick, and John Rawls have shaped and been used to justify the existence of governments and their actions.
In the field of the philosophy of education, progressive education as championed by John Dewey has had a profound impact on educational practices in the United States in the twentieth century. Carl von Clausewitz's political philosophy of war has had a profound effect on statecraft, international politics and military strategy in the 20th century, especially in the years around World War II.
Other important applications can be found in epistemology, which aid in understanding the notions of what knowledge, evidence, and justified belief are. The philosophy of science discusses the underpinnings of the scientific method. Aesthetics can help to interpret discussions of art. Ontology, even within the artificial intelligence definition, has had important consequences for logic and computer science.
In general, the various "philosophies of..." such as the philosophy of law, can provide workers in their respective fields with a deeper understanding of the theoretical or conceptual underpinnings of their fields.
Often, philosophy is seen as an investigation into an area not understood well enough to be its own branch of knowledge. What were once philosophical pursuits have evolved into the modern day fields of psychology, sociology, linguistics, and economics (among others).
The idea of philosophy as general concepts or principles of knowledge breaks down in fields of endeavor which require a certain type or level of personal performance. For instance, no principles of knowledge can tell a person how to write dramatic works comparable in quality to Shakespeare's or symphonies comparable to Beethoven's or to hit baseballs like Babe Ruth or sing songs like Elvis Presley. Yet, there is a certain state of mind conducive to peak performance in such fields. Sports psychology does bring knowledge to bear upon such endeavors. William McGaughey's book, "Rhythm and Self-Consciousness", approaches rhythm as a philosophical concept, discussing both its conscious pursuit and its limitations.
Philosophers on Philosophy
What is philosophy? Some noted philosophers have answered that question.
- "That philosophy only is the true one which reproduces most faithfully the statements of nature, and is written down, as it were, from nature's dictation, so that it is nothing but a copy and a reflection of nature, and adds nothing of its own, but is merely a repetition and echo." Francis Bacon, The Enlargement of Science, 1. 2, ch. 3.
- "To repeat abstractly, universally, and distinctly in concepts the whole inner nature of the world, and thus to deposit it as a reflected image in permanent concepts always ready for the faculty of reason, this and nothing else is philosophy." Arthur Schopenhauer, The World as Will and Representation, Vol. I, §68.
- Crystal, David, The Penguin Encyclopedia, Penguin Books, 2004, ISBN 0140515437
- Curley, Edwin, A Spinoza Reader, Princeton, 1994, ISBN 0691000670
- Descartes, René, Discourse on Method and Meditations on First Philosophy Fourth Edition, Hacket Publishing Company, 1998, ISBN 0872204219
- Dolan, John P., The Essential Erasmus, Meridian, 1964, ISBN 0452009723
- Durant, Will, The Story of Philosophy, Pocket, 1991, ISBN 0671739166
- Durant, Will and Durant, Ariel, Rousseau and Revolution: A History of Civilization in France, England, and Germany from 1756, and in the Remainder of Europe from 1715, to 1789 (Story of Civilization, 10), MJF Books, 1997, ISBN 1567310214
- Heidegger, Martin, Basic Writings : Second Edition, Revised and Expanded, HarperSanFrancisco. 1993, ISBN 0060637633
- Hobbes, Thomas, Leviathan, Penguin Classics, 1985
- Husserl, Edmund and Welton, Donn, The Essential Husserl: Basic Writings in Transcendental Phenomenology, Indiana University Press, 1999, ISBN 0253212731
- Kant, Immanuel, Critique of Pure Reason, Prometheus Books, 1990, ISBN 0879755962
- Kierkegaard, Søren, Fear and Trembling, Penguin Classics, 1986, ISBN 0140444491
- Kierkegaard, Søren, Concluding Unscientific Postscript, Princeton University Press, 1992, ISBN 0691020817
- Kung Fu Tze (Confucius), D. C. Lau (Translator), The Analects, Penguin Classics, 1998, ISBN 0140443487
- Lao Tze (Laozi), Stephen Hodge (Translator), Tao Te Ching, Barrons Educational Series, 2002, ISBN 0764121685
- Leibniz, G. W., Philosophical Essays, Hackett Publishing Company, 1989, ISBN 0872200639
- Mauter, Thomas (editor), The Penguin Dictionary of Philosophy, Penguin Books, 1998, ISBN 0140512500
- McGaughey, William, "Rhythm and Self-Consciousness: New Ideals for an Electronic Civilization", Thistlerose Publications, 2001. ISBN 0960563040.
- Nietzsche, Friedrich, Thus Spoke Zarathustra, Penguin Books, 1961, ISBN 0140441182
- Popper, Karl R., The Logic of Scientific Discovery, Routledge, 2002, ISBN 0415278449
- Sigmund, Paul E., The Selected Political Writings of John Locke, Norton, 2005, ISBN 0393964515
- Blumenau, Ralph. Philosophy and Living. ISBN 0907845339
- Craig, Edward. Philosophy: A Very Short Introduction. ISBN 0192854216
- Gaarder, Jostein. Sophie's World. ISBN 0425152251
- Higgins, Kathleen M. and Solomon, Robert C. A Short History of Philosophy. ISBN 0195101960
- Russell, Bertrand. The Problems of Philosophy. ISBN 019511552X
- Sober, E. (2001). Core Questions in Philosophy: A Text with Readings. Upper Saddle River, Prentice Hall. ISBN 0131898698
- Solomon, Robert C. Big Questions: A Short Introduction to Philosophy. ISBN 053416708X
- Warburton, Nigel. Philosophy: The Basics. ISBN 0415146941
- What Philosophy Is.
- Philosophy Now.
- The Philosophy Manuscripts.
- Syllabus for General Philosophy I, an introductory philosophy course currently offered by the Academe of Philosophical Studies at the University of No Where. Check back often for lectures, essays, articles, and other updates.
- Copleston, Frederick. Philosophy in Russia: From Herzen to Lenin and Berdyaev. ISBN 0268015694
- Critchley, Simon. Continental Philosophy: A Very Short Introduction. ISBN 0192853597
- Hamilton, Sue. Indian Philosophy: a Very Short Introduction. ISBN 0192853740
- Imbo, Samuel Oluoch. An Introduction to African Philosophy. ISBN 0847688410
- Kupperman, Joel J. Classic Asian Philosophy: A Guide to the Essential Texts. ISBN 0195133358
- Leaman, Oliver. A Brief Introduction to Islamic Philosophy. ISBN 0745619606
- Lee, Joe and Powell, Jim. Eastern Philosophy For Beginners. ISBN 0863162827
- Nagel, Thomas. What Does It All Mean? A Very Short Introduction to Philosophy. ISBN 0195052927
- Scruton, Roger. A Short History of Modern Philosophy. ISBN 0415267633
- Smart, Ninian. World Philosophies. ISBN 0415228522
- Tarnas, Richard. The Passion of the Western Mind: Understanding the Ideas That Have Shaped Our World View. ISBN 0345368096
- The Branches of Philosophy
- A Glossary of Terms
- Philosophic Classics: From Plato to Derrida (4th Edition) by Forrest E. Baird
- Classics of Philosophy (Vols. 1 & 2, 2nd edition) by Louis P. Pojman
- Classics of Philosophy: The 20th Century (Vol. 3) by Louis P. Pojman
- The English Philosophers from Bacon to Mill by Edwin Arthur Burtt
- European Philosophers from Descartes to Nietzsche by Monroe Beardsley
- Contemporary Analytic Philosophy: Core Readings by James Baillie
- Existentialism: Basic Writings (Second Edition) by Charles Guignon, Derk Pereboom
- The Phenomenology Reader by Dermot Moran, Timothy Mooney
- Medieval Islamic Philosophical Writings edited by Muhammad Ali Khalidi
- A Source Book in Indian Philosophy by Sarvepalli Radhakrishnan, Charles A. Moore
- A Source Book in Chinese Philosophy by Wing-tsit Chan
- Kim, J. and Ernest Sosa, Ed. (1999). Metaphysics: An Anthology. Blackwell Philosophy Anthologies. Oxford, Blackwell Publishers Ltd.
- The Oxford Handbook of Free Will (2004) edited by Robert Kane
- The Oxford Companion to Philosophy edited by Ted Honderich
- The Cambridge Dictionary of Philosophy by Robert Audi
- The Routledge Encyclopedia of Philosophy (10 vols.) edited by Edward Craig, Luciano Floridi (also available online by subscription); or
- The Concise Routledge Encyclopedia of Philosophy edited by Edward Craig (an abridgement)
- Routledge History of Philosophy (10 vols.) edited by John Marenbon
- History of Philosophy (9 vols.) by Frederick Copleston
- A History of Western Philosophy (5 vols.) by W. T. Jones
- Encyclopaedia of Indian Philosophies (8 vols.), edited by Karl H. Potter et al (first 6 volumes out of print)
- Indian Philosophy (2 vols.) by Sarvepalli Radhakrishnan
- A History of Indian Philosophy (5 vols.) by Surendranath Dasgupta
- History of Chinese Philosophy (2 vols.) by Fung Yu-lan, Derk Bodde
- Encyclopedia of Chinese Philosophy edited by Antonio S. Cua
- Encyclopedia of Eastern Philosophy and Religion by Ingrid Fischer-Schreiber, Franz-Karl Ehrhard, Kurt Friedrichs
- Companion Encyclopedia of Asian Philosophy by Brian Carr, Indira Mahalingam
- A Concise Dictionary of Indian Philosophy: Sanskrit Terms Defined in English by John A. Grimes
- History of Islamic Philosophy edited by Seyyed Hossein Nasr, Oliver Leaman
- History of Jewish Philosophy edited by Daniel H. Frank, Oliver Leaman
- A History of Russian Philosophy: From the Tenth to the Twentieth Centuries by Valerii Aleksandrovich Kuvakin
- Ayer, A. J. et al. Ed. (1994) A Dictionary of Philosophical Quotations. Blackwell Reference Oxford. Oxford, Basil Blackwell Ltd.
- Blackburn, S., Ed. (1996)The Oxford Dictionary of Philosophy. Oxford, Oxford University Press.
- Mauter, T., Ed. The Penguin Dictionary of Philosophy. London, Penguin Books.
- Runes, D., ED. (1942). The Dictionary of Philosophy. New York, The Philosophical Library, Inc.
- Angeles, P. A., Ed. (1992). The Harper Collins Dictionary of Philosophy. New York, Harper Perennial.
- Bunnin, N. et. al.,Ed.(1996) The Blackwell Companion to Philosophy. Blackwell Companions to Philosophy. Oxford, Blackwell Publishers Ltd.
- Popkin, R. H. (1999). The Columbia History of Western Philosophy. New York, Columbia University Press.
- An historical time line.
Areas of philosophy — Philosophy of:
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Eras of Philosophy
- Ancient Philosophy
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- EventWiki for Philosophy - A world wide list of current events, meetings, and discussion groups for Philosophy.
- Friesian Philosophy
- Think Philosophy, a discussion forum