Historically, the term refers to the philosophical thinking of Western civilization, beginning with Greek philosophy in ancient Greece. The word philosophy itself originated in Greece: philosophia (φιλοσοφια), literally, "the love of wisdom" (philein = "to love" + sophia = wisdom, in the sense of knowledge and the courage to act accordingly). The ancient Greek word for wisdom was probably related to ideas about universal knowledge claims in mathematics, astronomy, natural philosophy, music, and many other subjects as indicated by Plato's and Aristotle's works, along with many other ancient and medieval philosophers.
Western philosophy has had a strong influence on, and has been greatly influenced by, Western religion, science, and politics, and the philosophies of the Abrahamic religions (Jewish philosophy, Christian philosophy, Islamic philosophy). Indeed, the central concepts of these fields can be thought of as elements or branches of Western philosophy. To some of the ancient Greeks, these fields were often one and the same. Thus, philosophy is an expansive and ambiguous concept. Today, however, what generally distinguishes philosophy from other Western disciplines is the notion that philosophy is a more fundamental, classical, and universal form of thought than the other disciplines which sprouted from it.
The introduction of the terms "philosopher" and "philosophy" has been ascribed to the Greek thinker Pythagoras (see Diogenes Laertius: "De vita et moribus philosophorum", I, 12; Cicero: "Tusculanae disputationes", V, 8-9). The ascription is based on a passage in a lost work of Herakleides Pontikos, a disciple of Aristotle. It is considered to be part of the widespread legends of Pythagoras of this time. The term "philosophy" was made famous by Plato's and Aristotle's large volume of written works that survived for over two thousand years.
"Philosopher" replaced the word "sophist" (from sophoi), which was used to describe "wise men," teachers of rhetoric, who were important in Athenian democracy. Some of the most famous sophists were what we would now call philosophers, but Plato's dialogues often used the two terms to contrast those who are devoted to seeking wisdom (philosophers) from those who arrogantly and falsely claim to have it (sophists). Socrates (at least, as portrayed by Plato) frequently characterized the sophists as incompetents or charlatans, who hid their ignorance behind word play and flattery, and so convinced others of what was baseless or untrue. Moreover, the sophists were paid for their explorations. To this day, "sophist" is often used as a derogatory term for one who merely persuades rather than reasons.
The scope of philosophy in the ancient understanding, and the writings of (at least some of) the ancient philosophers, was all intellectual endeavors. This included the problems of philosophy as they are understood today; but it also included many other disciplines, such as pure mathematics and natural sciences such as physics, astronomy, and biology. (Aristotle, for example, wrote on all of these topics; and as late as the 17th century, these fields were still referred to as branches of "natural philosophy"). Over time, academic specialization and the rapid technical advance of the special sciences led to the development of distinct disciplines for these sciences, and their separation from philosophy: mathematics became a specialized science in the ancient world, and "natural philosophy" developed into the disciplines of the natural sciences over the course of the scientific revolution. Today, philosophical questions are usually explicitly distinguished from the questions of the special sciences, and characterized by the fact that (unlike those of the sciences) they are the sort of questions which are foundational and abstract in nature, and which are not amenable to being answered by experimental means.
Western philosophical subdisciplines
Western philosophers have often divided into several major branches based on the questions typically addressed by people working in different parts of the field. In the ancient world, the most influential division of the subject was the Stoics' division of philosophy into Logic, Ethics, and Physics (conceived as the study of the nature of the world, and including both natural science and metaphysics). In contemporary philosophy, specialties within the field are more commonly divided into metaphysics, epistemology, ethics and aesthetics (which together comprise axiology). Logic is sometimes included as another main branch of philosophy, sometimes as a separate science which philosophers often happen to work on, and sometimes just as a characteristically philosophical method applying to all branches of philosophy.
Within these broad branches there are now numerous sub-disciplines of philosophy. At the broadest level there is the division between Analytic and Continental Philosophy. For Continental Philosophy subdividing philosophy between "experts" is problematic for the very nature of the unifying task of philosophy itself, however, for most of Analytic Philosophy further divisions simplify the task for philosophers in each area.
The interest in particular sub-disciplines waxes and wanes over time; sometimes sub-disciplines become particularly hot topics and can occupy so much space in the literature that they almost seem like major branches in their own right. (Over the past 40 years or so philosophy of mind — which is, strictly speaking, mainly a sub-discipline of metaphysics — has taken on this position within Analytic philosophy, and has attracted so much attention that some suggest philosophy of mind as the paradigm for what contemporary Analytic philosophers do.)
Some of the many sub-disciplines within philosophy include:
- Axiology: the branch of philosophical enquiry that explores:
- Aesthetics: the study of basic philosophical questions about art and beauty. Sometimes philosophy of art is used to describe only questions about art, while "aesthetics" is the more general term. Likewise "aesthetics" sometimes applies more broadly than to merely the "philosophy of beauty": to include the sublime, humour, or fright - to any of the responses we might expect works of art or entertainment to elicit.
- 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 philosophers up until recent times have written; the interpretation of such philosophers; who influenced whom, and so forth. The history of philosophy can be approached either exegetically (in which case the main question is the interpretive question of what past philosophers mean and how the structure of their thought holds together) or critically (in which case the main question is the logical question of whether what past philosophers said was true or false, and what the philosophical consequences of their views are).
- Logic: the study of the standards of correct argumentation. The characteristic method of this study is the development of formal logic to symbolize and evaluate arguments; the characteristic topic is propositional logic, the logic of simple indicative statements. (Classical logic focused on the narrower subset of categorical reasoning by syllogism.) The more advanced topics in logic are generally extensions of formal logic to symbolize the logical relationships involved in particular aspects of the language -- such as modal logic, which deals with modal qualifiers like "possibly" and "necessarily", or temporal logic, which deals with the logical relationships established by the tense of a sentence.
- Meta-philosophy: the study of philosophical method and the nature and purpose of philosophy. The term "philosophy of philosophy" is sometimes used more or less as a synonym.
- Metaphysics (which includes ontology): the study of the most basic categories of things, such as existence, objects, properties, causality, and so forth. Metaphysics often is taken to include questions now studied by other philosophical subdisciplines, such as the mind-body problem and free will and determinism.
- Philosophy of education: the study of the purpose and most basic methods of education or learning.
- Philosophy of mathematics: the study of philosophical questions raised by mathematics, such as the nature of numbers, and what the nature and origins of our mathematical knowledge are.
- Philosophy of mind: the philosophical 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; the question what the "immediate objects" of perception are has been especially important.
- 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 or otherwise 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, the administration of justice and paternalism.
- Value theory: the study of the concept value. Also called theory of value. Sometimes this is taken to be equivalent to axiology (a term not in as much currency in the English-speaking world as it once was), and sometimes is taken to be, instead of a foundational field, an overarching field including ethics, aesthetics, and political philosophy, i.e., the philosophical subdisciplines that crucially depend on questions of value.
Philosophy contrasted with other disciplines
Originally the term "philosophy" was applied to all intellectual endeavours. Aristotle studied what would now be called biology, meteorology, physics, and cosmology, alongside his metaphysics and ethics. Even in the eighteenth century physics and chemistry were still classified as "natural philosophy", that is, the philosophical study of nature. Today these latter subjects are popularly referred to as sciences, and as separate from philosophy. But the distinction is not clear; some philosophers still contend that science retains an unbroken --and unbreakable -- link to philosophy.
More recently, psychology, economics, sociology, and linguistics were once the domain of philosophers insofar as they were studied at all, but now have only a weaker connection with the field. In the late twentieth century cognitive science and artificial intelligence could be seen as being forged in part out of "philosophy of mind."
Philosophy is done primarily through reflection. It does not tend to rely on experiment. However, in some ways philosophy is close to science in its character and method; some Analytic philosophers have suggested that the method of philosophical analysis allows philosophers to emulate the methods of natural science; Quine holds that philosist in any more than clarifying the arguments and claims of other sciences. This suggests that philosophy might be the study of meaning and reasoning generally; but some still would claim either that this is not a science, or that if it is it ought not to be pursued by philosophers.
All these views have something in common: whatever philosophy essentially is or is concerned with, it tends on the whole to proceed more "abstractly" than most (or most other) natural sciences. It does not depend as much on experience and experiment, and does not contribute as directly to technology. It clearly would be a mistake to identify philosophy with any one natural science; whether it can be identified with science very broadly construed is still an open question.
Philosophy of science
This is an active discipline pursued by both trained philosophers and scientists. Philosophers often refer to, and interpret, experimental work of various kinds (as in philosophy of physics and philosophy of psychology). But this is not surprising: such branches of philosophy aim at philosophical understanding of experimental work. It is not the philosophers in their capacity as philosophers, who perform the experiments and formulate the scientific theories under study. Philosophy of science should not be confused with science it studies any more than biology should be confused with plants and animals.
Theology and religious studies
Like philosophy, most religious studies are not experimental. Parts of theology, including questions about the existence and nature of gods, clearly overlap with philosophy of religion. Aristotle considered theology a branch of metaphysics, the central field of philosophy, and most philosophers prior to the twentieth century have devoted significant effort to theological questions. So the two are not unrelated. But other part of religious studies, such as the comparison of different world religions, can be easily distinguished from philosophy in just the way that any other social science can be distinguished from philosophy. These are closer to history and sociology, and involve specific observations of particular phenomena, here particular religious practices.
The Empiricist tradition in modern philosophy often held that religious questions are beyond the scope of human knowledge, and many have claimed that religious language is literally meaningless: there are not even questions to be answered. Some philosophers have felt that these difficulties in evidence were irrelevant, and have argued for, against, or just about religious beliefs on moral or other grounds. Nonetheless, in the main stream of twentieth century philosophy there are very few philosophers who give serious consideration to religious questions.
Mathematics uses very specific, rigorous methods of proof that philosophers sometimes (only rarely) try to emulate. Most philosophy is written in ordinary prose, and while it strives to be precise it does not usually attain anything like mathematical clarity. As a result, mathematicians hardly ever disagree about results, while philosophers of course do disagree about their results, as well as their methods.
The philosophy of mathematics is a branch of philosophy of science; but in many ways mathematics has a special relationship to philosophy. This is because the study of logic is a central branch of philosophy, and mathematics is a paradigm example of logic. In the late nineteenth and twentieth centuries logic made great advances, and mathematics has been proven to be reducible to logic (at least, to first-order logic with some set theory). The use of formal, mathematical logic in philosophy now resembles the use of math in science, although it is not as frequent.
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- Glyn Hughes' Squashed Philosophers - condensed and abridged versions of the books which defined the way The West thinks now.
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