Editing Epistemology (section)

== Major schools of thought ==
=== Skepticism and fallibilism ===
{{main|Skepticism|Falliblism|Epistemic relativism}}
[[Philosophical skepticism]] questions the human ability to attain knowledge by challenging the foundations upon which knowledge claims rest. Some skeptics limit their criticism to specific domains of knowledge. For example, [[Religious skepticism|religious skeptics]] say that it is impossible to know about the existence of deities or the truth of other religious doctrines. Similarly, moral skeptics challenge the existence of moral knowledge and metaphysical skeptics say that humans cannot know ultimate reality.<ref>{{multiref | {{harvnb|Cohen|1998|loc=§ Article Summary}} | {{harvnb|Hookway|2005|p=838}} | {{harvnb|Moser|2011|p=[https://books.google.com/books?id=1ETRCwAAQBAJ&pg=PA200 200]}} }}</ref> External world skepticism questions knowledge of external facts,<ref>{{multiref | {{harvnb|Greco|2011|p=[https://books.google.com/books?id=1ETRCwAAQBAJ&pg=PA108 108]}} | {{harvnb|McKinsey|2018|loc=Lead section}} }}</ref> whereas [[Problem of other minds|skepticism about other minds]] doubts knowledge of the mental states of others.<ref>{{multiref | {{harvnb|Gomes|Reed|2018|pp=700–702}} | {{harvnb|Avramides|2023|loc=Lead Section, § 1. The (Traditional) Epistemological Problem}} }}</ref>

Global skepticism is the broadest form of skepticism, asserting that there is no knowledge in any domain.<ref>{{multiref | {{harvnb|Hookway|2005|p=838}} | {{harvnb|Bergmann|2021|p=57}} | {{harvnb|Moreland|Craig|2003|p=[https://books.google.com/books?id=mPEN_EDiZuQC&pg=PA95 95]}} }}</ref> In [[ancient philosophy]], this view was embraced by [[Academic skepticism|academic skeptics]], whereas [[Pyrrhonian skeptics]] recommended the [[Epoche|suspension of belief]] to attain [[Ataraxia|tranquility]].<ref>{{multiref | {{harvnb|Hazlett|2014|p=[https://books.google.com/books?id=4INnAgAAQBAJ&pg=PA18 18]}} | {{harvnb|Levine|1999|p=[https://books.google.com/books?id=umYHtjvOhwIC&pg=PA11 11]}} }}</ref> Few epistemologists have explicitly defended global skepticism. The influence of this position stems from attempts by other philosophers to show that their theory overcomes the challenge of skepticism. For example, [[René Descartes]] used [[Cartesian doubt|methodological doubt]] to find facts that cannot be doubted.<ref>{{multiref | {{harvnb|Hookway|2005|p=838}} | {{harvnb|Comesaña|Klein|2024|loc=Lead section}} }}</ref>

One consideration in favor of global skepticism is the [[dream argument]]. It starts from the observation that, while people are dreaming, they are usually unaware of this. This inability to distinguish between dream and regular experience is used to argue that there is no certain knowledge since a person can never be sure that they are not dreaming.<ref>{{multiref | {{harvnb|Windt|2021|loc=§ 1.1 Cartesian Dream Skepticism}} | {{harvnb|Klein|1998|loc=§ 8. The Epistemic Principles and Scepticism}} | {{harvnb|Hetherington, "''Knowledge''"|ref=Hetherington, "''Knowledge''"|loc=§ 4. Sceptical Doubts About Knowing}} }}</ref>{{efn|The [[brain in a vat]] is a similar [[thought experiment]] assuming that a person does not have a body but is merely a brain receiving electrical stimuli indistinguishable from the stimuli a brain in a body would receive. This argument also leads to the conclusion of global skepticism based on the claim that it is not possible to distinguish stimuli representing the actual world from simulated stimuli.<ref>{{multiref | {{harvnb|Hookway|2005|p=838}} | {{harvnb|Steup|Neta|2024|loc=§ 6.1 General Skepticism and Selective Skepticism}} }}</ref>}} Some critics assert that global skepticism is [[self-refuting idea|self-refuting]] because denying the existence of knowledge is itself a knowledge claim. Another objection says that the abstract reasoning leading to skepticism is not convincing enough to overrule common sense.<ref>{{multiref | {{harvnb|Steup|Neta|2024|loc=§ 6.2 Responses to the Closure Argument}} | {{harvnb|Reed|2015|p=[https://books.google.com/books?id=geSrCQAAQBAJ&pg=PA75 75]}} }}</ref>

Fallibilism is another response to skepticism.<ref>{{harvnb|Cohen|1998|loc=§ 1. The Philosophical Problem of Scepticism, § 2. Responses to Scepticism}}</ref> Fallibilists agree with skeptics that absolute certainty is impossible. They reject the assumption that knowledge requires absolute certainty, leading them to the conclusion that fallible knowledge exists.<ref>{{multiref | {{harvnb|Hetherington, "''Fallibilism''"|ref=Hetherington, "''Fallibilism''"|loc=Lead section, § 9. Implications of Fallibilism: Knowing Fallibly?}} | {{harvnb|Rescher|1998|loc=§ Article Summary}} }}</ref> They emphasize the need to keep an open and inquisitive mind, acknowledging that doubt can never be fully excluded, even for well-established knowledge claims like thoroughly tested scientific theories.<ref>{{multiref | {{harvnb|Rescher|1998|loc=§ Article Summary}} | {{harvnb|Hetherington, "''Fallibilism''"|ref=Hetherington, "''Fallibilism''"|loc=§ 9. Implications of Fallibilism: Knowing Fallibly?}} }}</ref>

Epistemic relativism is related to skepticism but differs in that it does not question the existence of knowledge in general. Instead, epistemic relativists only reject the notion of universal epistemic standards or absolute principles that apply equally to everyone. This means that what a person knows depends on subjective criteria or social conventions used to assess epistemic status.<ref>{{multiref | {{harvnb|Carter|2017|p=[https://books.google.com/books?id=RzslDwAAQBAJ&pg=PA292 292]}} | {{harvnb|Luper|2004|pp=271–272}} }}</ref>

=== Empiricism and rationalism ===
{{main|Empiricism|Rationalism}}
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The debate between empiricism and rationalism centers on the origins of human knowledge. Empiricism emphasizes that [[sense experience]] is the primary source of all knowledge. Some empiricists illustrate this view by describing the mind as a [[blank slate]] that only develops ideas about the external world through the sense data received from the sensory organs. According to them, the mind can attain various additional insights by comparing impressions, combining them, generalizing to form more abstract ideas, and deducing new conclusions from them. Empiricists say that all these mental operations depend on sensory material and do not function on their own.<ref>{{multiref | {{harvnb|Lacey|2005|p=242}} | {{harvnb|Markie|Folescu|2023|loc=Lead section, § 1.2 Empiricism}} }}</ref>

Even though rationalists usually accept sense experience as one source of knowledge,{{efn|Some forms of extreme rationalism, found in [[ancient Greek philosophy]], see reason as the sole source of knowledge.<ref>{{harvnb|Lacey|2005a|p=783}}</ref>}} they argue that certain forms of knowledge are directly accessed through [[reason]] without sense experience,<ref name="auto2">{{multiref | {{harvnb|Lacey|2005a|p=783}} | {{harvnb|Markie|Folescu|2023|loc=Lead section, § 1. Introduction}} }}</ref> like knowledge of mathematical and logical truths.<ref>{{harvnb|Tieszen|2005|p=[https://books.google.com/books?id=2fgQ_fuCcKAC&pg=PA175 175]}}</ref> Some forms of rationalism state that the mind possesses [[Innatism|inborn ideas]], accessible without sensory assistance. Others assert that there is an additional cognitive faculty, sometimes called [[rational intuition]], through which people acquire nonempirical knowledge.<ref>{{multiref | {{harvnb|Lacey|2005a|p=783}} | {{harvnb|Markie|Folescu|2023|loc=Lead section, § 1. Introduction}} | {{harvnb|Hales|2009|p=[https://books.google.com/books?id=sINRmT4rZ5wC&pg=PA29 29]}} }}</ref> Some rationalists limit their discussion to the origin of concepts, saying that the mind relies on inborn [[Theory of categories|categories]] to understand the world and organize experience.<ref name="auto2"/>

=== Foundationalism and coherentism ===
{{main|Foundationalism|Coherentism}}
[[File:Foundationalism, coherentism, infinitism2.svg|thumb|upright=1.5|alt=Diagram with sections for foundationalism, coherentism, and infinitism, each depicting the relations between beliefs|Diagram of foundationalism, coherentism, and infinitism with arrows symbolizing support between beliefs. According to foundationalism, some basic beliefs are justified without support from other beliefs. According to coherentism, justification requires that beliefs mutually support each other. According to infinitism, justification requires that beliefs form infinite support chains.<ref>{{harvnb|Bradley|2015|pp=[https://books.google.com/books?id=qKXDCQAAQBAJ&pg=PA170 170–171]}}</ref>]]
Foundationalists and coherentists disagree about the structure of knowledge.<ref>{{multiref | {{harvnb|Audi|1988|pp=407–408}} | {{harvnb|Stairs|2017|pp=155–156}} | {{harvnb|Margolis|2007|p=[https://books.google.com/books?id=BeyuCgAAQBAJ&pg=PA214 214]}} | {{harvnb|Fei|2023|p=[https://books.google.com/books?id=Ot6uEAAAQBAJ&pg=PA79 79]}} }}</ref>{{efn|Both can be understood as responses to the [[regress problem]].<ref>{{harvnb|Bradley|2015|p=[https://books.google.com/books?id=qKXDCQAAQBAJ&pg=PA170 170]}}</ref> In ancient philosophy, the underlying problem was discussed as [[Agrippa's trilemma]]. The trilemma distinguises three ways of providing reasons for a statement: finding a justification that needs no further reason, circular reasoning by repeating a justification stated earlier, or providing an infinite justification chain.<ref>{{harvnb|Klein|2011|pp=[https://books.google.com/books?id=1ETRCwAAQBAJ&pg=PA484 484–485]}}</ref>}} Foundationalism distinguishes between basic and non-basic beliefs. A belief is basic if it is justified directly, meaning that its validity does not depend on the support of other beliefs.{{efn|The theory of classical foundationalism has a stronger requirement by saying that basic beliefs are [[Self-evidence|self-evident]] or indubitable.<ref>{{harvnb|Blaauw|Pritchard|2005|p=64}}</ref>}} A belief is non-basic if it is justified by another belief.<ref name="auto7">{{multiref | {{harvnb|Stairs|2017|pp=155–156}} | {{harvnb|Margolis|2007|p=[https://books.google.com/books?id=BeyuCgAAQBAJ&pg=PA214 214]}} }}</ref> For example, the belief that it rained last night is a non-basic belief if it is inferred from the observation that the street is wet.<ref>{{harvnb|Stairs|2017|p=155}}</ref> According to foundationalism, basic beliefs are the foundation on which all other knowledge is built while non-basic beliefs act as the superstructure resting on this foundation.<ref name="auto7"/>

Coherentists reject the distinction between basic and non-basic beliefs, saying that the justification of any belief depends on other beliefs. They assert that a belief must align with other beliefs to amount to knowledge. This occurs when beliefs are consistent and support each other. According to coherentism, justification is a [[Holism|holistic]] aspect determined by the whole system of beliefs, which resembles an interconnected web.<ref>{{multiref | {{harvnb|Stairs|2017|pp=156–157}} | {{harvnb|O'Brien|2006|p=[https://books.google.com/books?id=TOQcebWMstwC&pg=PA77 77]}} | {{harvnb|Slote|2021|p=[https://books.google.com/books?id=dCASEAAAQBAJ&pg=PA24 24]}} }}</ref>

[[Foundherentism]] is an intermediary position combining elements of both foundationalism and coherentism. It accepts the distinction between basic and non-basic beliefs while asserting that the justification of non-basic beliefs depends on coherence with other beliefs.<ref>{{multiref | {{harvnb|Ruppert|Schlüter|Seide|2016|p=[https://books.google.com/books?id=nF2mCwAAQBAJ&pg=PA59 59]}} | {{harvnb|Tramel|2008|pp=215–216}} }}</ref>

[[Infinitism]] presents a less common alternative perspective on the structure of knowledge. It agrees with coherentism that there are no basic beliefs while rejecting the view that beliefs can support each other in a [[Circular reasoning|circular manner]]. Instead, it argues that beliefs form infinite justification chains, in which each link of the chain supports the belief following it and is supported by the belief preceding it.<ref>{{multiref | {{harvnb|Bradley|2015|pp=[https://books.google.com/books?id=qKXDCQAAQBAJ&pg=PA170 170–171]}} | {{harvnb|Stairs|2017|pp=155–156}} }}</ref>

=== Internalism and externalism ===
{{main|Internalism and externalism#Epistemology|l1=Internalism and externalism (epistemology)}}
[[File:Alvin Goldman 1966.jpg|thumb|alt=Black and white photo of a bearded man wearing a suit and a tie|[[Alvin Goldman]] was an influential defender of externalism.{{sfn|BonJour|2016}}]]
The disagreement between internalism and externalism is about the sources of justification.<ref>{{multiref | {{harvnb|Pappas|2023|loc=Lead section}} | {{harvnb|Crumley II|2009|pp=159–160}} | {{harvnb|Fumerton|2011|loc=Lead section}} }}</ref>{{efn|The internalist-externalist debate in epistemology is different from the internalism-externalism debate in [[philosophy of mind]], which asks whether mental states depend only on the individual or also on their environment.<ref>{{multiref | {{harvnb|Bernecker|2013|loc=Note 1}} | {{harvnb|Wilson|2023}} }}</ref>}} Internalists say that justification depends only on factors within the individual, such as perceptual experience, memories, and other beliefs. This view emphasizes the importance of the cognitive perspective of the individual in the form of their mental states. It is commonly associated with the idea that the relevant factors are accessible, meaning that the individual can become aware of their reasons for holding a justified belief through introspection and reflection.<ref name="auto4">{{multiref | {{harvnb|Pappas|2023|loc=Lead section}} | {{harvnb|Poston|loc=Lead section}} | {{harvnb|Crumley II|2009|pp=159–160}} }}</ref>

[[Evidentialism]] is an influential internalist view, asserting that justification depends on the possession of [[evidence]].<ref>{{multiref | {{harvnb|Crumley II|2009|pp=99, 298}} | {{harvnb|Carter|Littlejohn|2021|loc=§ 9.3.3 An Evidentialist Argument}} | {{harvnb|Mittag|loc=Lead section}} }}</ref> In this context, evidence for a belief is any information in the individual's mind that supports the belief. For example, the perceptual experience of rain is evidence for the belief that it is raining. Evidentialists suggest various other forms of evidence, including memories, intuitions, and other beliefs.<ref>{{harvnb|Mittag|loc=§ 2b. Evidence}}</ref> According to evidentialism, a belief is justified if the individual's evidence supports it and they hold the belief on the basis of this evidence.<ref>{{harvnb|Crumley II|2009|pp=99, 298}}</ref>

Externalism, by contrast, asserts that at least some relevant factors of knowledge are external to the individual.<ref name="auto4"/> For instance, when considering the belief that a cup of coffee stands on the table, externalists are not primarily interested in the subjective perceptual experience that led to this belief. Instead, they focus on objective factors, like the quality of the person's eyesight, their ability to differentiate coffee from other beverages, and the circumstances under which they observed the cup.<ref>{{harvnb|Crumley II|2009|p=160}}</ref> A key motivation of many forms of externalism is that justification makes it more likely that a belief is true. Based on this view, justification is external to the extent that some factors contributing to this likelihood are not part of the believer's cognitive perspective.<ref name="auto4"/>

[[Reliabilism]] is an externalist theory asserting that a reliable connection between belief and truth is required for justification.<ref>{{multiref | {{harvnb|Crumley II|2009|pp=83, 301}} | {{harvnb|Olsson|2016}} }}</ref> Some reliabilists explain this in terms of reliable processes. According to this view, a belief is justified if it is produced by a reliable process, like perception. A belief-formation process is deemed reliable if most of the beliefs it generates are true. An alternative view focuses on beliefs rather than belief-formation processes, saying that a belief is justified if it is a reliable indicator of the fact it presents. This means that the belief tracks the fact: the person believes it because it is true but would not believe it otherwise.<ref>{{multiref | {{harvnb|Crumley II|2009|p=84}} | {{harvnb|Lyons|2016|pp=160–162}} | {{harvnb|Olsson|2016}} }}</ref>

[[Virtue epistemology]], another type of externalism, asserts that a belief is justified if it manifests intellectual virtues. Intellectual virtues are capacities or traits that perform cognitive functions and help people form true beliefs. Suggested examples include faculties, like vision, memory, and introspection, and [[character trait]]s, like open-mindedness.<ref>{{multiref | {{harvnb|Crumley II|2009|pp=175–176}} | {{harvnb|Baehr, "''Virtue Epistemology''"|ref=Baehr, "''Virtue Epistemology''"|loc=Lead section, § 1. Introduction to Virtue Epistemology}} }}</ref>