Philosophy

== Core branches ==
{{See also|Outline of philosophy#Branches of philosophy|Outline of philosophy#Philosophical schools of thought}}

Philosophical questions can be grouped into several branches. These groupings allow philosophers to focus on a set of similar topics and interact with other thinkers who are interested in the same questions. Epistemology, ethics, logic, and metaphysics are sometimes listed as the main branches.<ref>{{multiref |1={{harvnb|Brenner|1993|p=[https://books.google.com/books?id=DFoFDgAAQBAJ&pg=PT16 16]}} |2={{harvnb|Palmquist|2010|p=[https://books.google.com/books?id=NOKjGp7NHtUC&pg=PA800 800]}} |3={{harvnb|Jenicek|2018|p=[https://books.google.com/books?id=kWC1DwAAQBAJ&pg=PA31 31]}} }}</ref> There are many other subfields besides them and the different divisions are neither exhaustive nor mutually exclusive. For example, political philosophy, ethics, and [[aesthetics]] are sometimes linked under the general heading of [[value theory]] as they investigate [[normative]] or evaluative aspects.{{sfn|Schroeder|2021|loc=Lead Section: "In its broadest sense, 'value theory' is a catch-all label used to encompass all branches of moral philosophy, social and political philosophy, aesthetics, and sometimes feminist philosophy and the philosophy of religion – whatever areas of philosophy are deemed to encompass some 'evaluative' aspect."}} Furthermore, philosophical inquiry sometimes overlaps with other disciplines in the natural and social sciences, religion, and mathematics.<ref>{{multiref |1={{harvnb|Kenny|2018|p=[https://books.google.com/books?id=fn9xDwAAQBAJ&pg=PR20 20]}} |2={{harvnb|Lazerowitz|Ambrose|2012|pp=[https://books.google.com/books?id=LupI-JzfRZAC&pg=PA9 9]}} }}</ref>

=== Epistemology ===
{{Main|Epistemology}}
Epistemology is the branch of philosophy that studies knowledge. It is also known as ''theory of knowledge'' and aims to understand what knowledge is, how it arises, what its limits are, and what value it has. It further examines the nature of [[truth]], [[belief]], [[Justification (epistemology)|justification]], and [[Reason|rationality]].<ref>{{multiref |1={{harvnb|Martinich|Stroll|2023|loc=Lead Section, The Nature of Epistemology}} |2={{harvnb|Steup|Neta|2020|loc=Lead Section}} |3={{harvnb|Truncellito|loc=Lead Section}} |4={{harvnb|Greco|2021|loc=Article Summary}} }}</ref> Some of the questions addressed by epistemologists include "By what method(s) can one acquire knowledge?"; "How is truth established?"; and "Can we prove causal relations?"{{sfn|Mulvaney|2009|p=ix}}

Epistemology is primarily interested in [[declarative knowledge]] or knowledge of facts, like knowing that Princess Diana died in 1997. But it also investigates [[practical knowledge]], such as knowing how to ride a bicycle, and [[knowledge by acquaintance]], for example, knowing a celebrity personally.<ref>{{multiref |1={{harvnb|Steup|Neta|2020|loc=Lead Section, 2. What Is Knowledge?}} |2={{harvnb|Truncellito|loc=Lead Section, 1. Kinds of Knowledge}} |3={{harvnb|Colman|2009a|loc=[https://www.oxfordreference.com/display/10.1093/oi/authority.20110803095705926;jsessionid=A19D30BFCF6E02A0F21A87B805F10DEE Declarative Knowledge]}} }}</ref>

One area in epistemology is the ''[[analysis of knowledge]]''. It assumes that declarative knowledge is a combination of different parts and attempts to identify what those parts are. An influential theory in this area claims that knowledge has three components: it is a ''belief'' that is ''justified'' and ''true''. This theory is controversial and the difficulties associated with it are known as the [[Gettier problem]].<ref>{{multiref |1={{harvnb|Martinich|Stroll|2023|loc=The Nature of Knowledge}} |2={{harvnb|Truncellito|loc=Lead Section, 2. The Nature of Propositional Knowledge}} }}</ref> Alternative views state that knowledge requires additional components, like the absence of luck; different components, like the manifestation of [[Epistemic virtue|cognitive virtues]] instead of justification; or they deny that knowledge can be analyzed in terms of other phenomena.<ref>{{multiref |1={{harvnb|Ichikawa|Steup|2018|loc=[https://plato.stanford.edu/entries/knowledge-analysis/#GettProb § 3. The Gettier Problem, § 11. Knowledge First]}} |2={{harvnb|Truncellito|loc=§ 2d. The Gettier Problem}} }}</ref>

Another area in epistemology asks how people acquire knowledge. Often-discussed sources of knowledge are [[perception]], [[introspection]], [[memory]], [[inference]], and [[testimony]].<ref>{{multiref |1={{harvnb|Steup|Neta|2020|loc=5. Sources of Knowledge and Justification}} |2={{harvnb|Truncellito|loc=Lead Section, 4a. Sources of Knowledge}} }}</ref> According to [[empiricists]], all knowledge is based on some form of experience. Rationalists reject this view and hold that some forms of knowledge, like [[innate knowledge]], are not acquired through experience.<ref>{{multiref |1={{harvnb|Hetherington|loc=[https://iep.utm.edu/knowledg/#SH3c § 3c. Knowing Purely by Thinking]}} |2={{harvnb|Blackburn|2008|loc=[https://www.oxfordreference.com/display/10.1093/oi/authority.20110803095750220;jsessionid=BA317C21431AFF040A4F793D75E18752 Empiricism]}} |3={{harvnb|Blackburn|2008|loc=[https://www.oxfordreference.com/display/10.1093/oi/authority.20110803100405393;jsessionid=8337F6C845B873723233E9AEDB1025BC Rationalism]}} }}</ref> The [[regress problem]] is a common issue in relation to the sources of knowledge and the justification they offer. It is based on the idea that beliefs require some kind of reason or evidence to be justified. The problem is that the source of justification may itself be in need of another source of justification. This leads to an [[infinite regress]] or [[circular reasoning]]. [[Foundationalist]]s avoid this conclusion by arguing that some sources can provide justification without requiring justification themselves.<ref>{{multiref |1={{harvnb|Steup|Neta|2020|loc=4. The Structure of Knowledge and Justification}} |2={{harvnb|Truncellito|loc=3. The Nature of Justification}} }}</ref> Another solution is presented by [[coherentist]]s, who state that a belief is justified if it coheres with other beliefs of the person.{{sfn|Olsson|2021|loc=Lead Section, § 1. Coherentism Versus Foundationalism}}

Many discussions in epistemology touch on the topic of [[philosophical skepticism]], which raises doubts about some or all claims to knowledge. These doubts are often based on the idea that knowledge requires absolute certainty and that humans are unable to acquire it.<ref>{{multiref |1={{harvnb|Steup|Neta|2020|loc=6. The Limits of Cognitive Success}} |2={{harvnb|Truncellito|loc=4. The Extent of Human Knowledge}} |3={{harvnb|Johnstone|1991|p=[https://books.google.com/books?id=IBbQtkyrLE4C&pg=PA52 52]}} }}</ref>

=== Ethics ===
{{Main|Ethics}}
[[File:JohnStuartMill.jpg|thumb|alt=Drawing of John Stuart Mill|"The utilitarian doctrine is, that happiness is desirable, and the only thing desirable, as an end; all other things being only desirable as means to that end." — [[John Stuart Mill]], ''[[Utilitarianism (book)|Utilitarianism]]'' (1863){{sfn|Mill|1863|p=[https://en.wikisource.org/wiki/Utilitarianism/Chapter_4 51]}}]]

Ethics, also known as moral philosophy, studies what constitutes right [[Action (philosophy)|conduct]]. It is also concerned with the moral [[values (philosophy)|evaluation]] of character traits and institutions. It explores what the standards of [[morality]] are and how to live a good life.<ref>{{multiref |1={{harvnb|Audi|2006|pp=325–326}} |2={{harvnb|Nagel|2006|pp=379–380}} |3={{harvnb|Lambert|2023|p=[https://books.google.com/books?id=gNytEAAAQBAJ&pg=PT26 26]}} }}</ref> Philosophical ethics addresses such basic questions as "Are moral obligations relative?"; "Which has priority: well-being or obligation?"; and "What gives life meaning?"{{sfn|Mulvaney|2009|pp=vii–xi}}

The main branches of ethics are [[meta-ethics]], [[normative ethics]], and [[applied ethics]].<ref>{{multiref |1={{harvnb|Dittmer|loc=1. Applied Ethics as Distinct from Normative Ethics and Metaethics}} |2={{harvnb|Jeanes|2019|p=[https://books.google.com/books?id=BNUBEAAAQBAJ&pg=PT66 66]}} |3={{harvnb|Nagel|2006|pp=379–380}} }}</ref> Meta-ethics asks abstract questions about the nature and sources of morality. It analyzes the meaning of ethical concepts, like ''right action'' and ''[[obligation]]''. It also investigates whether ethical theories can be [[Moral relativism|true in an absolute sense]] and how to acquire knowledge of them.<ref>{{multiref |1={{harvnb|Dittmer|loc=1. Applied Ethics as Distinct from Normative Ethics and Metaethics}} |2={{harvnb|Jeanes|2019|p=[https://books.google.com/books?id=BNUBEAAAQBAJ&pg=PT66 66]}} |3={{harvnb|Nagel|2006|pp=390–391}} |4={{harvnb|Sayre-McCord|2023|loc=Lead Section}} }}</ref> Normative ethics encompasses general theories of how to distinguish between right and wrong conduct. It helps guide moral decisions by examining what moral obligations and rights people have. Applied ethics studies the consequences of the general theories developed by normative ethics in specific situations, for example, in the workplace or for medical treatments.<ref>{{multiref |1={{harvnb|Dittmer|loc=1. Applied Ethics as Distinct from Normative Ethics and Metaethics}} |2={{harvnb|Barsky|2009|p=[https://books.google.com/books?id=jqIzhD2lzj0C&pg=PA3 3]}} |3={{harvnb|Jeanes|2019|p=[https://books.google.com/books?id=BNUBEAAAQBAJ&pg=PT66 66]}} |4={{harvnb|Nagel|2006|pp=379–380, 390–391}} }}</ref>

Within contemporary normative ethics, consequentialism, [[deontology]], and [[virtue ethics]] are influential schools of thought.<ref>{{multiref |1={{harvnb|Dittmer|loc=1. Applied Ethics as Distinct from Normative Ethics and Metaethics}} |2={{harvnb|Nagel|2006|pp=382, 386–388}} }}</ref> ''Consequentialists'' judge actions based on their consequences. One such view is [[utilitarianism]], which argues that actions should increase overall happiness while minimizing suffering. ''Deontologists'' judge actions based on whether they follow moral duties, such as abstaining from lying or killing. According to them, what matters is that actions are in tune with those duties and not what consequences they have. ''Virtue theorists'' judge actions based on how the moral character of the agent is expressed. According to this view, actions should conform to what an ideally virtuous agent would do by manifesting virtues like [[generosity]] and [[honesty]].<ref>{{multiref |1={{harvnb|Dittmer|loc=1. Applied Ethics as Distinct from Normative Ethics and Metaethics}} |2={{harvnb|Nagel|2006|pp=382, 386–388}} |3={{harvnb|Hursthouse|Pettigrove|2022|loc=1.2 Practical Wisdom}} }}</ref>

=== Logic ===
{{Main|Logic}}

Logic is the study of [[Logical reasoning|correct reasoning]]. It aims to understand how to distinguish good from bad [[argument]]s.<ref>{{multiref |1={{harvnb|Hintikka|2019}} |2={{harvnb|Haack|1978|loc=Philosophy of Logics}} }}</ref> It is usually divided into formal and [[informal logic]]. Formal logic uses [[formal language|artificial languages]] with a precise symbolic representation to investigate arguments. In its search for exact criteria, it examines the structure of arguments to determine whether they are correct or incorrect. Informal logic uses non-formal criteria and standards to assess the correctness of arguments. It relies on additional factors such as content and context.<ref>{{multiref |1={{harvnb|Blair|Johnson|2000|pp=94–96}} |2={{harvnb|Walton|1996}} |3={{harvnb|Tully|2005|p=532}} |4={{harvnb|Johnson|1999|pp=265–267}} |5={{harvnb|Groarke|2021}} }}</ref>

Logic examines a variety of arguments. [[Deductive arguments]] are mainly studied by formal logic. An argument is deductively [[Validity (logic)|valid]] if the truth of its [[premise]]s ensures the truth of its conclusion. Deductively valid arguments follow a [[rule of inference]], like ''[[modus ponens]]'', which has the following [[logical form]]: "''p''; if ''p'' then ''q''; therefore ''q''". An example is the argument "today is Sunday; if today is Sunday then I don't have to go to work today; therefore I don't have to go to work today".<ref>{{multiref |1={{harvnb|Velleman|2006|pp=8, 103}} |2={{harvnb|Johnson-Laird|2009|pp=[https://wires.onlinelibrary.wiley.com/doi/abs/10.1002/wcs.20 8–10]}} |3={{harvnb|Dowden|2020|pp=334–336, 432}} }}</ref>

The premises of non-deductive arguments also support their conclusion, although this support does not guarantee that the conclusion is true.<ref>{{multiref |1={{harvnb|Dowden|2020|pp=432, 470}} |2={{harvnb|Anshakov|Gergely|2010|p=[https://books.google.com/books?id=OuyQgE_gf2QC&pg=PA128 128]}} }}</ref> One form is [[inductive reasoning]]. It starts from a set of individual cases and uses generalization to arrive at a universal law governing all cases. An example is the inference that "all ravens are black" based on observations of many individual black ravens.<ref>{{multiref |1={{harvnb|Vickers|2022}} |2={{harvnb|Nunes|2011|pp=[https://books.google.com/books?id=xZuSxo4JxoAC 2066–2069]|loc=Logical Reasoning and Learning}} |3={{harvnb|Dowden|2020|pp=432–449, 470}} }}</ref> Another form is [[abductive reasoning]]. It starts from an observation and concludes that the best explanation of this observation must be true. This happens, for example, when a doctor diagnoses a disease based on the observed symptoms.<ref>{{multiref |1={{harvnb|Douven|2022}} |2={{harvnb|Koslowski|2017|pp=366–368|loc=Abductive Reasoning and Explanation}} |3={{harvnb|Nunes|2011|pp=[https://books.google.com/books?id=xZuSxo4JxoAC 2066–2069]|loc=Logical Reasoning and Learning}} }}</ref>

Logic also investigates incorrect forms of reasoning. They are called ''[[fallacies]]'' and are divided into [[Formal fallacy|formal]] and [[informal fallacies]] based on whether the source of the error lies only in the form of the argument or also in its content and context.<ref>{{multiref |1={{harvnb|Hansen|2020}} |2={{harvnb|Dowden|2023}} |3={{harvnb|Dowden|2020|p=290}} |4={{harvnb|Vleet|2011|p=[https://books.google.com/books?id=UCFYUGRG5dcC&pg=PR9 ix]}} }}</ref>

=== Metaphysics ===
{{Main|Metaphysics}}
[[File:Aristotle, Metaphysics, Incunabulum.jpg|upright=0.9|thumb|left|alt=Incunabulum showing the beginning of Aristotle's ''Metaphysics''|The beginning of [[Metaphysics (Aristotle)|Aristotle's ''Metaphysics'']] in an [[incunabulum]] decorated with hand-painted miniatures.]]

Metaphysics is the study of the most general features of [[reality]], such as existence, [[Object (philosophy)|objects]] and their [[Property (philosophy)|properties]], [[Mereology|wholes and their parts]], [[space]] and [[time]], [[Event (philosophy)|events]], and [[Causality|causation]].<ref>{{multiref |1={{harvnb|van Inwagen|Sullivan|Bernstein|2023}} |2={{harvnb|Craig|1998}} |3={{harvnb|Audi|2006|loc=§ Metaphysics}} }}</ref> There are disagreements about the precise definition of the term and its meaning has changed throughout the ages.{{sfn|van Inwagen|Sullivan|Bernstein|2023|loc=Lead Section}} Metaphysicians attempt to answer basic questions including "[[Why is there something rather than nothing?]]"; "Of what does reality ultimately consist?"; and "Are humans free?"{{sfn|Mulvaney|2009|pp=ix–x}}

Metaphysics is sometimes divided into general metaphysics and specific or special metaphysics. General metaphysics investigates being as such. It examines the features that all entities have in common. Specific metaphysics is interested in different kinds of being, the features they have, and how they differ from one another.<ref>{{multiref |1={{harvnb|van Inwagen|Sullivan|Bernstein|2023}} |2={{harvnb|Craig|1998}} |3={{harvnb|Gracia|1999|p=[https://books.google.com/books?id=PrUkAQAAMAAJ& 149]}} }}</ref>

An important area in metaphysics is [[ontology]]. Some theorists identify it with general metaphysics. Ontology investigates concepts like [[being]], [[Becoming (philosophy)|becoming]], and reality. It studies the [[categories of being]] and asks what exists on the most fundamental level.<ref>{{multiref |1={{harvnb|Haaparanta|Koskinen|2012|p=[https://books.google.com/books?id=yz8sko5zVyUC&pg=PA454 454]}} |2={{harvnb|Fiet|2022|p=[https://books.google.com/books?id=nK1jEAAAQBAJ&pg=PA133 133]}} |3={{harvnb|Audi|2006|loc=§ Metaphysics}} |4={{harvnb|van Inwagen|Sullivan|Bernstein|2023|loc=1. The Word 'Metaphysics' and the Concept of Metaphysics}} }}</ref> Another subfield of metaphysics is [[philosophical cosmology]]. It is interested in the essence of the world as a whole. It asks questions including whether the universe has a beginning and an end and whether it was created by something else.<ref>{{multiref |1={{harvnb|Audi|2006|loc=§ Metaphysics}} |2={{harvnb|Coughlin|2012|p=[https://books.google.com/books?id=QPFoAgAAQBAJ&pg=PA15 15]}} }}</ref>

A key topic in metaphysics concerns the question of whether reality only consists of physical things like matter and energy. Alternative suggestions are that mental entities (such as [[soul]]s and [[experience]]s) and [[Abstract and concrete|abstract entities]] (such as numbers) exist apart from physical things. Another topic in metaphysics concerns the problem of [[Identity (philosophy)|identity]]. One question is how much an entity can change while still remaining the same entity.{{sfn|Audi|2006|loc=§ Metaphysics}} According to one view, entities have [[essence|essential]] and [[Accident (philosophy)|accidental features]]. They can change their accidental features but they cease to be the same entity if they lose an essential feature.<ref>{{multiref |1={{harvnb|Robertson Ishii|Atkins|2023|loc=[https://plato.stanford.edu/entries/essential-accidental/ Lead Section]}} |2={{harvnb|Espín|Nickoloff|2007|p=[https://books.google.com/books?id=k85JKr1OXcQC&pg=PA8 8]}} }}</ref> A central distinction in metaphysics is between [[particular]]s and [[universals]]. Universals, like the color red, can exist at different locations at the same time. This is not the case for particulars including individual persons or specific objects.<ref>{{multiref |1={{harvnb|Lowe|2005|p=683}} |2={{harvnb|Kuhlmann|2010|loc=Ontologie: 4.2.1 Einzeldinge und Universalien}} }}</ref> Other metaphysical questions are whether the past [[Determinism|fully determines]] the present and what implications this would have for the existence of [[free will]].<ref>{{multiref |1={{harvnb|Kane|2009|pp=[https://books.google.com/books?id=i7PG-Vk824UC&pg=PA22 22–23]}} |2={{harvnb|Kane|2013|p=[https://books.google.com/books?id=LRV-Tzcry8EC&pg=RA3-PT258 258]}} }}</ref>

=== Other major branches ===
{{See also|List of philosophies}}
There are many other subfields of philosophy besides its core branches. Some of the most prominent are aesthetics, philosophy of language, philosophy of mind, philosophy of religion, philosophy of science, and political philosophy.<ref>{{multiref |1={{harvnb|Stambaugh|1987|loc=[https://www.encyclopedia.com/environment/encyclopedias-almanacs-transcripts-and-maps/philosophy-overview Philosophy: An Overview]}} |2={{harvnb|Phillips|2010|p=16}} |3={{harvnb|Ramos|2004|p=[https://books.google.com/books?id=y2XkGpGBzbsC&pg=PA4 4]}} |4={{harvnb|Shand|2004|pp=[https://books.google.com/books?id=uoCh8mpbZO4C&pg=PA9 9–10]}} }}</ref>

[[Aesthetics]] in the philosophical sense is the field that studies the nature and appreciation of [[beauty]] and other aesthetic properties, like [[the sublime]].<ref>{{multiref |1={{harvnb|Smith|Brown|Duncan|2019|p=[https://books.google.com/books?id=QkmqDwAAQBAJ&pg=PT174 174]}} |2={{harvnb|McQuillan|2015|pp=[https://books.google.com/books?id=NObaDwAAQBAJ&pg=PA122 122–123]}} |3={{harvnb|Janaway|2005|p=9|loc=Aesthetics, History Of}} }}</ref> Although it is often treated together with the [[Aesthetics#Aesthetics and the philosophy of art|philosophy of art]], aesthetics is a broader category that encompasses other aspects of experience, such as natural beauty.<ref>{{multiref |1={{harvnb|Nanay|2019|p=4}} |2={{harvnb|McQuillan|2015|pp=[https://books.google.com/books?id=NObaDwAAQBAJ&pg=PA122 122–123]}} }}</ref> In a more general sense, aesthetics is "critical reflection on art, culture, and [[nature]]".<ref>{{multiref |1={{harvnb|Kelly|1998|p=ix}} |2={{harvnb|Riedel|1999}} }}</ref> A key question in aesthetics is whether beauty is an objective feature of entities or a subjective aspect of experience.<ref>{{multiref |1={{harvnb|McQuillan|2015|pp=[https://books.google.com/books?id=NObaDwAAQBAJ&pg=PA122 122–123]}} |2={{harvnb|Sartwell|2022|loc=[https://plato.stanford.edu/entries/beauty/ Lead Section, 1. Objectivity and Subjectivity]}} }}</ref> Aesthetic philosophers also investigate the nature of aesthetic experiences and [[aesthetic judgment|judgments]]. Further topics include the essence of [[works of art]] and the processes involved in creating them.<ref>{{multiref |1={{harvnb|Smith|Brown|Duncan|2019|p=[https://books.google.com/books?id=QkmqDwAAQBAJ&pg=PT174 174]}} |2={{harvnb|McQuillan|2015|pp=[https://books.google.com/books?id=NObaDwAAQBAJ&pg=PA122 122–123]}} }}</ref>

The [[philosophy of language]] studies the nature and function of [[language]]. It examines the concepts of [[Meaning (philosophy)|meaning]], [[reference]], and truth. It aims to answer questions such as how words are related to things and how language affects human [[thought]] and understanding. It is closely related to the disciplines of logic and linguistics.<ref>{{multiref |1={{harvnb|Audi|2006|loc=§ Philosophy of Language}} |2={{harvnb|Russell|Fara|2013|pp=[https://books.google.com/books?id=czr880lvAPIC&pg=PR2 ii, 1–2]}} |3={{harvnb|Blackburn|2022|loc=Lead Section}} }}</ref> The philosophy of language rose to particular prominence in the early 20th century in [[analytic philosophy]] due to the works of [[Frege]] and Russell. One of its central topics is to understand how sentences get their meaning. There are two broad theoretical camps: those emphasizing the formal [[truth conditions]] of sentences{{efn|The truth conditions of a sentence are the circumstances or states of affairs under which the sentence would be true.{{sfn|Birner|2012|p=[https://books.google.com/books?id=9pQ3KPKY1hkC&pg=PT33 33]}}}} and those investigating circumstances that determine when it is suitable to use a sentence, the latter of which is associated with [[speech act theory]].<ref>{{multiref |1={{harvnb|Wolf|2023|loc=§§ 1.a-b, 3–4}} |2={{harvnb|Ifantidou|2014|p=[https://books.google.com/books?id=4bKKAwAAQBAJ&pg=PT12 12]}} }}</ref>

The [[philosophy of mind]] studies the nature of mental phenomena and how they are related to the physical world.<ref>{{multiref |1={{harvnb|Lowe|2000|pp=[https://books.google.com/books?id=mH12kYm1RKAC&pg=PA1 1–2]}} |2={{harvnb|Crumley|2006|pp=[https://books.google.com/books?id=Yf4eAAAAQBAJ&pg=PA2 2–3]}} }}</ref> It aims to understand different types of [[conscious]] and [[Unconscious mind|unconscious]] [[mental states]], like [[belief]]s, [[desire]]s, [[intention]]s, [[feeling]]s, [[sense|sensations]], and free will.<ref>{{multiref |1={{harvnb|Audi|2006|loc=§ Philosophy of Mind}} |2={{harvnb|Heidemann|2014|p=[https://books.google.com/books?id=6pTJAwAAQBAJ&pg=PT140 140]}} }}</ref> An influential intuition in the philosophy of mind is that there is a distinction between the inner experience of objects and their existence in the external world. The [[mind-body problem]] is the problem of explaining how these two types of thing—mind and matter—are related. The main traditional responses are [[materialism]], which assumes that matter is more fundamental; [[idealism]], which assumes that mind is more fundamental; and [[Mind–body dualism|dualism]], which assumes that mind and matter are distinct types of entities. In contemporary philosophy, another common view is [[Functionalism (philosophy of mind)|functionalism]], which understands mental states in terms of the functional or causal roles they play.<ref>{{multiref |1={{harvnb|Heil|2013|pp=1–3, 9, 12–13}} |2={{harvnb|Weir|2023|pp=[https://books.google.com/books?id=jUXAEAAAQBAJ&pg=PT10 10–11]}} |3={{harvnb|Shiraev|2010|pp=[https://books.google.com/books?id=r4xBJXxnnx8C&pg=PA83 83–84]}} |4={{harvnb|Polger|loc=Lead Section}} }}</ref> The mind-body problem is closely related to the [[hard problem of consciousness]], which asks how the physical brain can produce [[Qualia|qualitatively subjective experiences.]]<ref>{{multiref |1={{harvnb|Heil|2013|pp=1–3, 12–13}} |2={{harvnb|Weisberg|loc=Lead Section, 1. Stating the Problem}} }}</ref>

The [[philosophy of religion]] investigates the basic concepts, assumptions, and arguments associated with [[religion]]. It critically reflects on what religion is, how to define the [[divine]], and whether one or more gods exist. It also includes the discussion of [[worldview]]s that reject religious doctrines.<ref>{{multiref |1={{harvnb|Taliaferro|2023|loc=Lead Section, § 5.2}} |2={{harvnb|Burns|2017|pp=[https://books.google.com/books?id=YWU9DwAAQBAJ i, 1–3]}} |3={{harvnb|Audi|2006|loc=§ Philosophy of Religion}} |4={{harvnb|Meister|loc=Lead Section}} }}</ref> Further questions addressed by the philosophy of religion are: "How are we to interpret religious language, if not literally?";{{sfn|Taliaferro|2023|loc=§ 1}} "Is divine omniscience compatible with free will?";{{sfn|Taliaferro|2023|loc=§ 5.1.1}} and, "Are the great variety of world religions in some way compatible in spite of their apparently contradictory theological claims?"{{sfn|Taliaferro|2023|loc=§ 6}} It includes topics from nearly all branches of philosophy.<ref>{{multiref |1={{harvnb|Taliaferro|2023|loc=Introduction}} |2={{harvnb|Audi|2006|loc=§ Philosophy of Religion}} }}</ref> It differs from [[theology]] since theological debates typically take place within one religious tradition, whereas debates in the philosophy of religion transcend any particular set of theological assumptions.<ref>{{multiref |1={{harvnb|Bayne|2018|pp=1–2}} |2={{harvnb|Louth|Thielicke|2014}} }}</ref>

The [[philosophy of science]] examines the fundamental concepts, assumptions, and problems associated with science. It reflects on what science is and how to distinguish it from [[pseudoscience]]. It investigates the methods employed by scientists, how their application can result in knowledge, and on what assumptions they are based. It also studies the purpose and implications of science.<ref>{{multiref |1={{harvnb|Audi|2006|loc=§ Philosophy of Science}} |2={{harvnb|Kitcher|2023}} |3={{harvnb|Losee|2001|pp=[https://books.google.com/books?id=lQN6DwAAQBAJ&pg=PA1 1–3]}} |4={{harvnb|Wei|2020|p=[https://books.google.com/books?id=U2wNEAAAQBAJ&pg=PA127 127]}} |5={{harvnb|Newton-Smith|2000|pp=2–3}}}}</ref> Some of its questions are "What counts as an adequate explanation?";{{sfn|Newton-Smith|2000|pp=7}} "Is a scientific law anything more than a description of a regularity?";{{sfn|Newton-Smith|2000|pp=5}} and "Can some special sciences be explained entirely in the terms of a more general science?"{{sfn|Papineau|2005|pp=855–856}} It is a vast field that is commonly divided into the philosophy of the [[natural sciences]] and the philosophy of the [[social sciences]], with further subdivisions for each of the individual sciences under these headings. How these branches are related to one another is also a question in the philosophy of science. Many of its philosophical issues overlap with the fields of metaphysics or epistemology.<ref>{{multiref |1={{harvnb|Papineau|2005|p=852}} |2={{harvnb|Audi|2006|loc=§ Philosophy of Science}} }}</ref>

[[Political philosophy]] is the philosophical inquiry into the fundamental principles and ideas governing political systems and societies. It examines the basic concepts, assumptions, and arguments in the field of [[politics]]. It investigates the nature and purpose of [[government]] and compares its different forms.<ref>{{multiref |1={{harvnb|Molefe|Allsobrook|2021|pp=[https://books.google.com/books?id=wKQeEAAAQBAJ&pg=PA8 8–9]}} |2={{harvnb|Moseley|loc=Lead Section}} |3={{harvnb|Duignan|2012|pp=[https://books.google.com/books?id=ye-cAAAAQBAJ&pg=PA5 5–6]}} |4={{harvnb|Bowle|Arneson|2023|loc=Lead Section}} |5={{harvnb|McQueen|2010|p=[https://books.google.com/books?id=ho5KEAAAQBAJ&pg=PA162 162]}} }}</ref> It further asks under what circumstances the use of political power is [[Political legitimacy|legitimate]], rather than a form of simple violence.<ref>{{multiref |1={{harvnb|Molefe|Allsobrook|2021|pp=[https://books.google.com/books?id=wKQeEAAAQBAJ&pg=PA8 8–9]}} |2={{harvnb|Howard|2010|p=4}} }}</ref> In this regard, it is concerned with the distribution of political power, social and material goods, and [[legal rights]].{{sfn|Wolff|2006|pp=1–2}} Other topics are [[justice]], [[liberty]], [[Social equality|equality]], [[sovereignty]], and [[nationalism]].{{sfn|Molefe|Allsobrook|2021|pp=[https://books.google.com/books?id=wKQeEAAAQBAJ&pg=PA8 8–9]}} Political philosophy involves a general inquiry into normative matters and differs in this respect from [[political science]], which aims to provide empirical descriptions of actually existing states.<ref>{{multiref |1={{harvnb|Moseley|loc=Lead Section}} |2={{harvnb|Molefe|Allsobrook|2021|pp=[https://books.google.com/books?id=wKQeEAAAQBAJ&pg=PA8 8–9]}} }}</ref> Political philosophy is often treated as a subfield of ethics.{{sfn|Audi|2006|loc=§ Subfields of Ethics}} Influential schools of thought in political philosophy are [[liberalism]], [[conservativism]], socialism, and [[anarchism]].<ref>{{multiref |1={{harvnb|Moseley|loc=Lead Section, § 3. Political Schools of Thought}} |2={{harvnb|McQueen|2010|p=[https://books.google.com/books?id=ho5KEAAAQBAJ&pg=PA162 162]}} }}</ref>