The definition of philosophy is a philosophical question in its own right. There are two rudimentary schools in philosophical work. One takes the role of philosophy to be purely the study of the a priori (literally, "before experience") and philosophers who work in this vein are involved in the analysis of various concepts and of our language. The other role philosophy has taken to have is to decipher 'the meaning of life' and philosophers who work in this vein have taken themselves to understand our experience, prescribe ethical behavior,etc. Philosophers, especially those in that first tradition, feel that philosophy studies the kind of knowledge that is not given to us in experience. Philosophy studies such concepts as existence, goodness, knowledge,particulars, universals, content, and beauty. It asks questions such as "What is goodness?", "Is knowledge even possible?", "What is the nature of perception", "What is the relationship between beliefs and language?", "What is mathematics?", etc.
"Philo-" comes from the Greek word philein, meaning to love, and "-sophy" comes from the Greek sophia, or wisdom. Originally the scope of philosophy was all intellectual endeavor. It has long since come to mean the study of an especially abstract, nonexperimental intellectual endeavor. In fact, philosophy is itself a notoriously difficult word to define; the question "What is philosophy?" is itself, famously, a vexing philosophical question. It is often observed that philosophers are unique in the extent to which they disagree about what their field "is".
Popularly, the word "philosophy" is often used to mean any form of wisdom, or any person's perspective on life (as in "philosophy of life") or basic principles behind or method of achieving something (as in "my philosophy about driving on highways"). That is different from the academic meaning, and it is the academic meaning which is used here.
For further considerations about the very notion of philosophy, please see definition of philosophy.
Philosophers divide the long history of Western philosophy into ancient philosophy, medieval philosophy, modern philosophy, and contemporary philosophy. Ancient philosophy was dominated by the trio of Socrates, Plato, and Aristotle. In medieval philosophy, topics in metaphysics and philosophy of religion held sway, and the most important names included Duns Scotus, Peter Abelard and Aquinas. Modern philosophy generally means philosophy from 1600 until about 1900, and which includes many distinguished early modern philosophers, such as René Descartes, Thomas Hobbes, John Locke, David Hume, Immanuel Kant, and G.W.F Hegel. Ninteenth-century philosophy is often treated as its own period, as it was dominated by post-Kantian German and idealist philosophers like Georg Wilhelm Friedrich Hegel, Karl Marx, and F. H. Bradley; two other important thinkers were John Stuart Mill and Friedrich Nietzsche.
In the twentieth century, philosophers in Europe and the United States took diverging paths. The so-called analytic philosophers, including Bertrand Russell, G. E. Moore, and Ludwig Wittgenstein, were centered in Oxford and Cambridge, and were joined by logical empiricists emigrating from Austria and Germany (e.g., Rudolph Carnap) and their students and others in the United States (e.g., W. V. Quine) and other English-speaking countries.
John Dewey was an American philosopher and founder of the school of philosophy known as pragmatism. He had an enormous influence on American education - indeed, he is sometimes referred to as the ?father of American education?--but that is mostly by people who agree with his ideas.
On the continent of Europe (especially Germany and France), the phenomenologist Germans Edmund Husserl and Martin Heidegger led the way, followed soon by Jean-Paul Sartre and other existentialists; this led via other "isms" to postmodernism, which dominates schools of Critical Theory as well as philosophy departments in France and Germany.
As with any field of academic study, philosophy has a number of subdisciplines. Philosophy in fact seems to have a huge number of subdisciplines, in no small part due to the fact that there tends to be a "philosophy of" nearly everything else that is studied. The beginner is invited particularly to pay attention to logic, metaphysics, philosophy of mind, philosophy of language, epistemology, philosophy of science, ethics, and political philosophy as--arguably, of course--the "central disciplines" of philosophy.
- Aesthetics: the study of basic philosophical questions about art and beauty.
- Epistemology: the study of knowledge, its nature, possibility, and justification.
- Ethics: the study of what makes actions right or wrong, and of how theories of right action can be applied to special moral problems. Subdisciplines include meta-ethics, value theory, theory of conduct, and applied ethics.
- History of philosophy: the study of what dead philosophers have written, its interpretation, and who influenced whom.
- Logic: the study of the standards of correct argumentation.
- Meta-philosophy: the study of philosophical method and the goals of philosophy.
- Metaphysics: the study of the most basic categories of things, such as existence, objects, properties, causality, and so forth.
- Philosophy of biology: the philosophical study of some basic concepts of biology, including the notion of a species.
- Philosophy of education: the study of the purpose and most basic methods of education or learning.
- Philosophy of language: the study of the concepts of meaning and truth.
- Philosophy of mind: the study of the nature of the mind, and its relation to the body and the rest of the world.
- Philosophy of perception: the philosophical study of topics related to perception, especially the question what the "immediate objects" of perception are.
- Philosophy of physics: the philosophical study of some basic concepts of physics, including space, time, and force.
- Philosophy of psychology: the study of some fundamental questions about the methods and concepts of psychology and psychiatry, such as the meaningfulness of Freudian concepts; this is sometimes treated as including philosophy of mind.
- Philosophy of religion: the study of the meaning of the concept of God and of the rationality of belief in the existence of God.
- Philosophy of science: includes not only, as subdisciplines, the "philosophies of" the special sciences (i.e., physics, biology, etc.), but also questions about induction, scientific method, scientific progress, etc.
- Philosophy of social sciences: the philosophical study of some basic concepts, methods, and presuppositions of social sciences such as sociology and economics.
- Political philosophy: the study of basic topics concerning government, including the purpose of the state, political justice, political freedom, the nature of law, and the justification of punishment.
There are quite a few others; feel free to complete the list.
How to get started in philosophy
It is a platitude (at least among people who write introductions to philosophy) that everybody has a philosophy, though they might not all realize it or be able to defend it. If you're already interested in studying philosophy, your reason might be to improve the way you live or think somehow, or you simply wish to get acquainted with one of the most ancient areas of human thought. On the other hand, if you don't see what all the fuss is about, it might help to read the motivation to philosophize, which explains what motivates many people to "do philosophy," and get an introduction to philosophical method, which is important to understanding how philosophers think. It might also help to acquaint yourself with some considerations about just what philosophy is.
Philosophy has applications. The most obvious applications are those in ethics--applied ethics in particular--and in political philosophy. The political philosophies of John Locke, Jean-Jacques Rousseau, Karl Marx, and John Stuart Mill have shaped and been used to justify governments and their actions. Philosophy of education deserves special mention, as well; progressive education as championed by John Dewey has had a profound impact on educational practices in the United States in the twentieth century.
Other important, but less immediate applications can be found in epistemology, which might help one to regulate one's notions of what knowledge, evidence, and justified belief are. Philosophy of science discusses the underpinnings of the scientific method, among other topics sometimes useful to scientists. Aesthetics can help to interpret discussions of art. Even ontology, surely the most abstract and least practical-seeming branch of philosophy, has had important consequences for logic and computer science. In general, the various "philosophies of," such as philosophy of law, can provide workers in their respective fields with a deeper understanding of the theoretical or conceptual underpinnings of their fields.
Moreover, recently, there has been developing a burgeoning profession devoted to applying philosophy to the problems of ordinary life: philosophical counseling.
Eventually, we would like the following lists introduced properly as separate sections of this article (which is an article-in-progress, of course!).
altruism -- anti-realism -- Buddhist philosophy -- coherentism -- Confucianism -- consequentialism -- constructivism -- deconstructionism-- Discordianism -- egoism -- eudaimonism -- foundationalism -- hedonism -- historical materialism -- irrealism -- justified true belief -- nominalism -- Objectivism -- philosophical pessimism -- psychological egoism -- Platonism -- realism -- reliabilism -- Taoism -- Transcendentalism -- utilitarianism -- Populism and Nationalism -- Irrationalism and Aestheticism -- Stoicism -- [etc. continue the list please]
What are our priorities for writing in this area? To help develop a list of the most basic topics in Philosophy, please see Philosophy basic topics.