Misplaced Pages

Epistemology: Difference between revisions

Article snapshot taken from Wikipedia with creative commons attribution-sharealike license. Give it a read and then ask your questions in the chat. We can research this topic together.
Browse history interactively← Previous editNext edit →Content deleted Content addedVisualWikitext
Revision as of 23:24, 16 August 2005 editBaronLarf (talk | contribs)Administrators18,547 editsm Reverted edits by 67.182.157.6 to last version by Ed Poor← Previous edit Revision as of 15:41, 17 August 2005 edit undo172.198.112.61 (talk) majority side is trying to control content entailing logical fallacy by force of numbers, blocking contributors of the oppositionNext edit →
Line 1: Line 1:
'''Epistemology''', from the ] words ''episteme'' (knowledge) and ''logos'' (word/speech) is the branch of ] that deals with the nature, origin and scope of ]. '''Epistemology''', from the ] words ''episteme'' (knowledge) and ''logos'' (word/speech) is the study of ].



==Definition of knowledge== ==Definition of knowledge==
<!-- deleted section containing fallacious ] of knowledge and belief, two different things - see talk-->


===Defining knowledge===
=== Distinguishing ''knowing that'' from ''knowing how'' ===


'''Knowledge''' is simply that which is known, to a high level of confidence, to be in accord with the actual state of affairs because it is supported by proof, where proof is the cogency of evidence that compels acceptance, or the process of establishing the validity of a statement by derivation from other statements in accordance with principles of reasoning.
Suppose that ] says to you: "The fastest ] stroke is the ]. One performs the front crawl by oscillating the legs at the hip, and moving the arms in an approximately circular motion". Here, Fred has ] of swimming and how to perform the front crawl.

However, if Fred acquired this propositional knowledge from an ], he will not have acquired the ] of swimming: he has some propositional knowledge, but does not have any ] or "know-how". In general, one can demonstrate know-how by performing the task in question, but it is harder to demonstrate propositional knowledge. ] popularised the term ] to distinguish the ability to do something from the ability to describe how to do something. ] had previously made a similar point in discussing the characteristics of ]. His ideas are summed up in the ] "efficient practice precedes the theory of it". Someone with the ability to perform the appropriate moves is said to be able to swim, even if that person cannot precisely identify what it is they do in order to swim. This distinction is often traced back to ], who used the term '']'' or ''skill'' for ''knowledge how'', and the term '']'' for a more robust kind of knowledge in which claims can be true or false.

===Knowledge and belief===
]

There are two slightly different meanings of ''belief'' that must be distinguished. In the first sense John might "believe in" his cousin Joe. This may mean that he is willing to loan Joe money, trusting in his paying it back. In this sense, John ''might'' say, "I know it is safer to fly than drive, yet I don't believe it" in which case John doesn't trust in the pilots of commercial aircraft, even though as a cognitive matter he may understand the pertinent statistics.

In the second sense of belief, to believe something can just mean to think that it is true. That is, to believe P is to do no more than to think, for whatever reason, that P is the case. It is ''this'' sort of belief that philosophers most often mean when they are discussing knowledge. The reason is that in order to know something, one must think that it is true - one must believe (in the second sense) it to be the case.

Consider someone saying "I know that P, but I don't think P is true". The person making this utterance has, in a profound sense, contradicted themselves. If one knows that P, then, amongst other things, one thinks that P is indeed true. If one thinks that P is true, then one believes P. (''See: ]''.)

Knowledge is distinct from ] and ]. If someone claims to believe something, they are claiming that they think that it is the ]. But of course, it ''might'' turn out that they were mistaken, and that what they thought was true was actually false. This is not the case with knowledge. For example, suppose that Jeff thinks that a particular bridge is safe, and attempts to cross it; unfortunately the bridge collapses under his weight. We might say that Jeff ''believed'' that the bridge was safe, but that his belief was mistaken. We would ''not'' say that he ''knew'' that the bridge was safe, because plainly it was not. For something to count as ''knowledge'', it must be true.

Similarly, two people can ''believe'' things that are mutually contradictory, but they cannot ''know'' (unequivocal) things that are mutually contradictory. For example, Jeff can ''believe'' the bridge safe, while Jenny believes it unsafe. But Jeff cannot ''know'' the bridge is safe and Jenny ''know'' that the bridge is unsafe. Two people cannot ''know'' contradictory things.

One has to be somewhat careful in the application of this principle, though, because "mutually contradictory" turns out to be a complicated notion. After all, Jenny may be more risk averse (a subjective matter) than Jeff, and both may be using "safe" relative to their own risk aversion, i.e. "safe enough for me to walk on with comfort." In this case, Jenny can know it to be unsafe and Jeff can know it to be safe.

===Justified true belief===

<!-- NOTE TO THE PERSON WHO KEEPS REMOVING THIS TEXT: ***PLEASE*** EXPLAIN YOURSELF ON THE 'DISCUSSION' PAGE! WE ARE CONSIDERING ARBITRATION! -->

The most influential writing on knowledge is the '']'' account written by ], in which he further develops the definition of knowledge. We know that, for something to count as knowledge, it must be true, and be believed to be true. Plato argues that this is insufficient, and that in addition one must have a ''reason'' or ''justification'' for that belief.

Plato defined knowledge as ] ] ].
One implication of this definition is that one cannot be said to "know" something just because one believes it and that belief subsequently turns out to be true. An ill person with no medical training but a generally optimistic attitude might believe that she will recover from her illness quickly, but even if this belief turned out to be true, on the Theaetetus account the patient did not '''know''' that she would get well, because her belief lacked justification.

Knowledge, therefore, is distinguished from true belief by its '''justification''', and much of epistemology is concerned with how true beliefs might be properly justified. This is sometimes referred to as the ].

The Theaetetus definition agrees with the common sense notion that we can believe things without knowing them. Whilst ''knowing'' p ] that p is true, ''believing'' in p does not, since we can have false beliefs. It also implies that we believe everything that we know. That is, the things we know form a ] of the things we believe.

===The problem of defining knowledge===


For most of philosophical history, "knowledge" was taken to mean belief that was justified as true to an absolute certainty. Any less justified beliefs were called mere "probable opinion." This viewpoint still prevailed at least as late as ]'s early 20th century book ''The Problems of Philosophy''. In the decades that followed, however, the notion that the belief had to be justified ''to a certainty'' lost favour. For most of philosophical history, "knowledge" was taken to mean belief that was justified as true to an absolute certainty. Any less justified beliefs were called mere "probable opinion." This viewpoint still prevailed at least as late as ]'s early 20th century book ''The Problems of Philosophy''. In the decades that followed, however, the notion that the belief had to be justified ''to a certainty'' lost favour.
Line 44: Line 14:
In the ], ] criticised the Theaetetus definition of knowledge by pointing out situations in which a believer has a true belief justified to a reasonable degree, but not to a certainty, and yet in the situations in question, everyone would agree that the believer does not have knowledge. In the ], ] criticised the Theaetetus definition of knowledge by pointing out situations in which a believer has a true belief justified to a reasonable degree, but not to a certainty, and yet in the situations in question, everyone would agree that the believer does not have knowledge.


Another current objection to the Theaetetus definition of knowledge is that the statement, "Knowledge is ... belief" suffers from the logical fallacy of ] of two different things.
=== A priori versus a posteriori knowledge ===


==Justification==
Western ] for centuries have distinguished between two kinds of knowledge: ] and ] knowledge.


Much of epistemology has been concerned with seeking ways to justify statements.
A priori knowledge is knowledge gained or justified by ] alone, without the direct or indirect influence of any particular experience (here, ''experience'' usually means observation of the world through sense perception. See '']'', below, for clarification.)


Any statement, P, is justified by demonstrating that P is in accord with the actual state of affairs, or that the validity of P is derived from other statements in accordance with principles of reasoning.
A posteriori knowledge is any other sort of knowledge; that is, knowledge the attainment or justification of which requires reference to experience. This is also called ''empirical knowledge''.

One of the fundamental questions in ] is whether there is any non-trivial a priori knowledge. Generally speaking ] believe that there is, while ] believe that all knowledge is ultimately derived from some kind of external experience.

The fields of knowledge most often suggested as having a priori status are ] and ], which deal primarily with abstract, formal objects.

Empiricists have traditionally denied that even these fields could be a priori knowledge. Two common arguments are that these sorts of knowledge can only be derived from experience (as ] argued), and that they do not constitute "real" knowledge (as ] argued).

==Justification==


Much of epistemology has been concerned with seeking ways to justify knowledge statements.


===Irrationalism=== ===Irrationalism===
Line 66: Line 27:
Some approaches to justifying knowledge are not rational &mdash; that is, they reject the notion that justification must obey ] or reason. ] started out as a materialistic political philosophy, but is sometimes redefined as the apparently absurd doctrine that there can be no justification for knowledge claims &mdash; absurd because it appears to be self-contradictory to claim that one ''knows'' that knowledge is impossible, but perhaps for a nihilist, self-contradiction is simply unimportant. Some approaches to justifying knowledge are not rational &mdash; that is, they reject the notion that justification must obey ] or reason. ] started out as a materialistic political philosophy, but is sometimes redefined as the apparently absurd doctrine that there can be no justification for knowledge claims &mdash; absurd because it appears to be self-contradictory to claim that one ''knows'' that knowledge is impossible, but perhaps for a nihilist, self-contradiction is simply unimportant.


'']'' is the use of non-rational methods to arrive at beliefs and accepting such beliefs as knowledge. For example, believing that something is true based on emotion would be regarded as epistemological mysticism, whereas believing based on deductive logic or scientific experiment would not. An instance of this may be when one bases one's belief in the existence of something merely on one's ''desire'' that it should exist. Another example might be the use of a daisy's petals and the phrase "he loves me/ he loves me not" while they are plucked to determine whether Romeo returns Juliet's affections. The mysticism in this example would be the assumption that such a method has predictive or indicative powers without rational evidence of such. In both of these examples, belief is not justified through a rational means. Mysticism need not be an intentional process: one may engage in mysticism without being aware of it. '']'' is the use of non-rational methods to arrive at belief and assuming that belief to be knowledge. For example, believing that something is true based an emotion would be regarded as epistemological mysticism, whereas believing based on deductive logic or scientific experiment would not. An instance of this may be when one bases one's belief in the existence of something merely on one's ''desire'' that it should exist. Another example might be the use of a daisy's petals and the phrase "he loves me/ he loves me not" while they are plucked to determine whether Romeo returns Juliet's affections. The mysticism in this example would be the assumption that such a method has predictive powers without rational evidence of such. In both of these examples, belief is not justified through a rational means. Mysticism need not be an intentional process: one may engage in mysticism without being aware of it.


===Rationality=== ===Rationality===
Line 72: Line 33:
If one does not reject rationality, but still wishes to maintain that knowledge claims cannot be or are not justified, one might be termed a ]. Here we are on firmer philosophical ground; since skeptics accept the validity of ], they can present logical ]s for their case. If one does not reject rationality, but still wishes to maintain that knowledge claims cannot be or are not justified, one might be termed a ]. Here we are on firmer philosophical ground; since skeptics accept the validity of ], they can present logical ]s for their case.


For instance, the ] has it that one can ask for the justification for any statement of knowledge. If that justification takes the form of another statement, one can again reasonably ask for that statement also to be justified, and so forth. This appears to lead to an infinite regress, with every statement justified by some other statement. For instance, the ] has it that one can ask for the justification for any statement of knowledge. If that justification takes the form of another statement, one can again reasonably ask for it to be justified, and so forth. This appears to lead to an infinite regress, with every statement justified by some other statement.
It would be impossible to check that each justification is satisfactory, and so relying on such a series quickly leads to skepticism. It would be impossible to check that each justification is satisfactory, and so relying on such a series quickly leads to scepticism.


Alternately, one might claim that some knowledge statements do not require justification. Much of the history of epistemology is the story of conflicting philosophical doctrines claiming that this or that type of knowledge statement has special status. This view is known as ]. Alternately, one might claim that some knowledge statements do not require justification. Much of the history of epistemology is the story of conflicting philosophical doctrines claiming that this or that type of knowledge statement has special status. This view is known as ].
Line 85: Line 46:
Synthetic statements, on the other hand, have distinct subjects and ]s. An example would be ''my father's brother is overweight''. Synthetic statements, on the other hand, have distinct subjects and ]s. An example would be ''my father's brother is overweight''.


Although anticipated by ], this distinction was more clearly formulated by ], and later given a more formal shape by ]. ] noted in the '']'' that analytic statements "express no thoughts", that is, that they tell us nothing new; although analytic statements do not require justification, they are singularly uninformative. ], in his famous '']'', challenged the legitimacy of the analytic-synthetic distinction altogether. Although anticipated by ], this distinction was more clearly formulated by ], and later given a more formal shape by ]. ] noted in the '']'' that analytic statements "express no thoughts", that is, that they tell us nothing new; although analytic statements do not require justification, they are singularly uninformative.


==Epistemological theories== ==Epistemological theories==
Line 95: Line 56:
] believe that there are ] or ] that are not derived from ]. These ideas, however, may be justified by experience. These ideas may in some way derive from the structure of the human ], or they may exist independently of the mind. If they exist independently, they may be understood by a human mind once it reaches a necessary degree of sophistication. ] believe that there are ] or ] that are not derived from ]. These ideas, however, may be justified by experience. These ideas may in some way derive from the structure of the human ], or they may exist independently of the mind. If they exist independently, they may be understood by a human mind once it reaches a necessary degree of sophistication.


The epitome of the rationalist view is ]' '']'', in which the skeptic is invited to consider that the mere fact that he doubts this claim implies that there is a doubter. Because doubting is a kind of thinking, the claim must be correct. ] derived a rationalist system in which there is only one substance, ]. ] derived a system in which there are an infinite number of substances, his '']''. The epitome of the rationalist view is ]' '']'', in which the skeptic is invited to consider that the mere fact that they doubt implies that there is a doubter. ] derived a rationalist system in which there is only one substance, ]. ] derived a system in which there are an infinite number of substances, his '']''.


===Empiricism=== ===Empiricism===


] claim knowledge is a product of human ]. Statements of observations take pride of place in empiricist theory. ] holds simply that our ideas and theories need to be tested against ], and accepted or rejected on the basis of how well they ''correspond'' to ''observed facts''. The central problem for epistemology then becomes explaining this ]. ] claim knowledge is a product of human ]. Statements of observations take pride of place in empiricist theory. ] holds simply that our ideas and theories need to be tested against ], and accepted or rejected on the basis of how well they ''correspond'' to the ''facts''. The central problem for epistemology then becomes explaining this ].


Empiricism is associated with ]. While there can be little doubt about the effectiveness of science, there is much philosophical debate about how and why science works. The ] was once favoured as the reason for scientific success, but recently difficulties in the ] have led to a rise in ]. Empiricism is associated with ]. While there can be little doubt about the effectiveness of science, there is much philosophical debate about how and why science works. The ] was once favoured as the reason for scientific success, but recently difficulties in the ] have led to a rise in ].


] is sometimes associated with a tradition called ], or ], which places higher emphasis on ideas about reality rather than on experiences of reality. ] is often confused with ], which places higher emphasis on ideas about reality than on experiences with reality themselves.


====Naïve realism==== ====Naïve realism====


], or Common-Sense realism is the belief that there is a real external world, and that our perceptions are caused directly by that world. It has its foundation in ] in that an object being there causes us to see it. Thus, it follows, the world remains as it is when it is perceived - when it is not being perceived - ''a room is still there once we exit''. The opposite theory to this is ]. Naïve realism fails to take into account the psychology of ]. (''See: ]''.) ], or Common-Sense realism is the belief that there is a real external world, and that our perceptions are caused directly by that world. It has its foundation in ] in that an object being there causes us to see it. Thus, it follows, the world remains as it is when it is perceived - when it is not being perceived - ''a room is still there once we exit''. The opposite theory to this is ]. Naïve realism fails to take into account the psychology of ].


====Objectivism==== ====Objectivism====
Line 119: Line 80:
===Idealism=== ===Idealism===


] holds that what we refer to and perceive as the external world is in some way an artifice of the mind. Analytic statements (for example, mathematical truths), are held to be true without reference to the external world, and these are taken to be exemplary knowledge statements. ], ] and ] held various idealist views. Idealism is itself a '']'' thesis, but has important epistemological consequences. ] holds that what we refer to and perceive as the external world is in some way an artifice of the mind. Analytic statements (for example, mathematical truths), are held to be true without reference to the external world, and these are taken to be exemplary knowledge statements. ], ] and ] held various idealist views.


===Phenomenalism=== ===Phenomenalism===


] is a development from ]'s claim that to be is to be perceived. According to phenomenalism, when you see a tree, you see a certain perception of a brown shape, when you touch it, you get a perception of pressure against your palm. On this view, one shouldn't think of objects as distinct substances, which interact with our senses so that we may perceive them; rather we should conclude that all that really exists is the perception itself. ] is a development from ]'s claim that to be is to be perceived. According to phenomenalism, when you see "a tree" you see a certain perception of a brown shape. On this view, one shouldn't think of objects as distinct substances, which interact with our senses so that we may perceive them; rather we should conclude that all that really exists is the perception itself.


Nowadays this point of view is rejected as solipsism, the fallacious argument that maybe all that really exists is perception, because there is no proof this hypothesis is false, which is the ] of argment _ad ignorantiam_).
===Pragmatism===

] about knowledge holds that what is important about knowledge is that it solves certain problems that are constrained both by the world and by human purposes. The place of knowledge in human activity is to resolve the problems that arise in conflicts between belief and action. Pragmatists are also typically committed to the use of the experimental method in all forms of inquiry, a non-skeptical fallibilism about our current store of knowledge, and the importance of knowledge proving itself through future testing.


==Contemporary approaches== ==Contemporary approaches==
Line 144: Line 103:


Some examples of these new definitions include (where '''S''' is the belief holder and '''p''' is the belief): Some examples of these new definitions include (where '''S''' is the belief holder and '''p''' is the belief):
* ‘Applicable Knowledge’, attributed to Zacharyas Boufoy-Bastick, states that " '''S''' can know '''p''' if and only if '''p''' is true, and '''S''' is ''pragmatically'' justified in believing '''p'''.

**This is a development in Epistemology, attained through merging Foundationism and ], which supposes that “the acceptance of belief as knowledge lies in observable and practical use”. Within the context of this theory, since an element cannot be shown to belong to the widest-possible system of beliefs, foundational knowledge is unattainable. From this clause, ‘Applicable Knowledge’ states that one must be satisfied with something less than Foundationism-based absolute knowledge and, hence, that the ‘pragmatic’ condition be added to the tripartite definition of knowledge.
* ]'s ''"No accident account of knowledge"'', which defines knowledge as "'''S''' knows '''p''' if and only if it is not at all accidental that '''S''''s belief in '''p''' is true". * ]'s ''"No accident account of knowledge"'', which defines knowledge as "'''S''' knows '''p''' if and only if it is not at all accidental that '''S''''s belief in '''p''' is true".
* The ''"Defeasibilty account of knowledge"'', where "There is no other proposition ('''q'''), such that if '''S''' became justified in believing '''q''', '''S''' would no longer be justified in believing '''p'''". Under this account, '''q''' is known as the ''"defeater"''. * The ''"Defeasibilty account of knowledge"'', where "There is no other proposition ('''q'''), such that if '''S''' became justified in '''q''', '''S''' would no longer be justified in '''p'''". Under this account, '''q''' is known as the ''"defeater"''.
* The ''"Causational Account"'', where "The fact of '''p''' causes '''S''''s belief in '''p'''" * The ''"Causational Account"'', where "The fact of '''p''' causes '''S''''s belief in '''p'''"
** A problem with the Causational account is that ''deviant causal chains'' can emerge. Philosopher ] added that "Fact that '''p''', causes fact that '''q''', causes '''S''''s belief in '''q''' is not knowledge, but belief in '''q''', from which '''p''' is inferred, is knowledge". However, there must be an awareness of the causal chain. ** A problem with the Causational account is that ''deviant causal chains'' can emerge. Philosopher ] added that "Fact that '''p''', causes fact that '''q''', causes '''S''''s belief in '''q''' is not knowledge, but belief in '''q''', from which '''p''' is inferred, is knowledge". However, there must be an awareness of the causal chain.
Line 158: Line 118:
Some epistemologists have attempted to find strengthened criteria for knowledge that are not subject to the sorts of counterexamples Gettier and his many successors have produced. Most of these attempts involve adding a fourth condition or placing restrictions on the kind or degree of justification suitable to produce knowledge. None of these projects has yet gained widespread acceptance. Kirkham has argued that this is because the only definition that could ever be immune to all such counterexamples is the original one that prevailed from ancient times through Russell: to qualify as an item of knowledge, a belief must not only be true and justified, the evidence for the belief must ''necessitate'' its truth. But this conclusion is generally resisted since it easily appears to entail a sweeping skepticism. Some epistemologists have attempted to find strengthened criteria for knowledge that are not subject to the sorts of counterexamples Gettier and his many successors have produced. Most of these attempts involve adding a fourth condition or placing restrictions on the kind or degree of justification suitable to produce knowledge. None of these projects has yet gained widespread acceptance. Kirkham has argued that this is because the only definition that could ever be immune to all such counterexamples is the original one that prevailed from ancient times through Russell: to qualify as an item of knowledge, a belief must not only be true and justified, the evidence for the belief must ''necessitate'' its truth. But this conclusion is generally resisted since it easily appears to entail a sweeping skepticism.


==Epistemic theories==
Gettier's article was published in 1963. Right after that, for a good decade or more, there was an enormous number of articles trying to supply the missing fourth condition of knowledge. The big project was to try to figure out the "X" in the equation, Knowledge = belief + truth + justification + X. Whenever someone proposed an answer, someone else would come up with a new counterexample to shoot down that definition.

Some of the proposed solutions involve factors external to the agent. These responses are therefore called ]. For example, one externalist response to the Gettier problem is to say that the justified, true belief must be caused (in the right sort of way) by the relevant facts.

==See also==
===Epistemic theories===


* ] by ] * ] by ]
Line 182: Line 137:
** ] ** ]


===Epistemic philosophers=== ==Epistemic philosophers==


* ] * ]
Line 233: Line 188:
* ] * ]


===Related topics=== ==Related topics==


*] *]
Line 279: Line 234:


] ]
] ]
] ]
] ]
] ]
] ]
] ]
]
]
] ]
]
]
] ]
] ]
] ]
]
]
]
] ]
]
] ]
] ]
]
]
] ]

Revision as of 15:41, 17 August 2005

Epistemology, from the Greek words episteme (knowledge) and logos (word/speech) is the study of knowledge.


Definition of knowledge

Defining knowledge

Knowledge is simply that which is known, to a high level of confidence, to be in accord with the actual state of affairs because it is supported by proof, where proof is the cogency of evidence that compels acceptance, or the process of establishing the validity of a statement by derivation from other statements in accordance with principles of reasoning.

For most of philosophical history, "knowledge" was taken to mean belief that was justified as true to an absolute certainty. Any less justified beliefs were called mere "probable opinion." This viewpoint still prevailed at least as late as Bertrand Russell's early 20th century book The Problems of Philosophy. In the decades that followed, however, the notion that the belief had to be justified to a certainty lost favour.

In the 1960s, Edmund Gettier criticised the Theaetetus definition of knowledge by pointing out situations in which a believer has a true belief justified to a reasonable degree, but not to a certainty, and yet in the situations in question, everyone would agree that the believer does not have knowledge.

Another current objection to the Theaetetus definition of knowledge is that the statement, "Knowledge is ... belief" suffers from the logical fallacy of conflation of two different things.

Justification

Much of epistemology has been concerned with seeking ways to justify statements.

Any statement, P, is justified by demonstrating that P is in accord with the actual state of affairs, or that the validity of P is derived from other statements in accordance with principles of reasoning.


Irrationalism

Some approaches to justifying knowledge are not rational — that is, they reject the notion that justification must obey logic or reason. Nihilism started out as a materialistic political philosophy, but is sometimes redefined as the apparently absurd doctrine that there can be no justification for knowledge claims — absurd because it appears to be self-contradictory to claim that one knows that knowledge is impossible, but perhaps for a nihilist, self-contradiction is simply unimportant.

Mysticism is the use of non-rational methods to arrive at belief and assuming that belief to be knowledge. For example, believing that something is true based an emotion would be regarded as epistemological mysticism, whereas believing based on deductive logic or scientific experiment would not. An instance of this may be when one bases one's belief in the existence of something merely on one's desire that it should exist. Another example might be the use of a daisy's petals and the phrase "he loves me/ he loves me not" while they are plucked to determine whether Romeo returns Juliet's affections. The mysticism in this example would be the assumption that such a method has predictive powers without rational evidence of such. In both of these examples, belief is not justified through a rational means. Mysticism need not be an intentional process: one may engage in mysticism without being aware of it.

Rationality

If one does not reject rationality, but still wishes to maintain that knowledge claims cannot be or are not justified, one might be termed a skeptic. Here we are on firmer philosophical ground; since skeptics accept the validity of reason, they can present logical arguments for their case.

For instance, the regress argument has it that one can ask for the justification for any statement of knowledge. If that justification takes the form of another statement, one can again reasonably ask for it to be justified, and so forth. This appears to lead to an infinite regress, with every statement justified by some other statement. It would be impossible to check that each justification is satisfactory, and so relying on such a series quickly leads to scepticism.

Alternately, one might claim that some knowledge statements do not require justification. Much of the history of epistemology is the story of conflicting philosophical doctrines claiming that this or that type of knowledge statement has special status. This view is known as Foundationalism.

One can also avoid the regress if one supposes that the assumption that a knowledge statement can only be supported by another knowledge statement is simply misguided. Coherentism holds that a knowledge statement is not justified by some small subset of other knowledge statements, but by the entire set. That is, a statement is justified if it coheres with all other knowledge claims in the system. This has the advantage of avoiding the infinite regress without claiming special status for some particular sorts of statements. But since a system might still be consistent and yet simply wrong, it raises the difficulty of ensuring that the whole system corresponds in some way with the truth.

Synthetic and analytic statements

Some statements are such that they appear not to need any justification once one understands their meaning. For example, consider: my father's brother is my uncle. This statement is true in virtue of the meaning of the terms it contains, and so it seems frivolous to ask for a justification for saying it is true. Philosophers call such statements analytic. More technically, a statement is analytic if the concept in the predicate is included in the concept in the subject. In the example, the concept of uncle (the predicate) is included in the concept of being my father's brother (the subject). Not all analytic statements are as trivial as this example. Mathematical statements are often taken to be analytic.

Synthetic statements, on the other hand, have distinct subjects and predicates. An example would be my father's brother is overweight.

Although anticipated by David Hume, this distinction was more clearly formulated by Immanuel Kant, and later given a more formal shape by Frege. Wittgenstein noted in the Tractatus that analytic statements "express no thoughts", that is, that they tell us nothing new; although analytic statements do not require justification, they are singularly uninformative.

Epistemological theories

It is common for epistemological theories to avoid skepticism by adopting a foundationalist approach. To do this, they argue that certain types of statements have a special epistemological status — that of not needing to be justified. So it is possible to classify epistemological theories according to the type of statement that each argues has this special status.

Rationalism

Rationalists believe that there are a priori or innate ideas that are not derived from sense experience. These ideas, however, may be justified by experience. These ideas may in some way derive from the structure of the human mind, or they may exist independently of the mind. If they exist independently, they may be understood by a human mind once it reaches a necessary degree of sophistication.

The epitome of the rationalist view is Descartes' I think therefore I am, in which the skeptic is invited to consider that the mere fact that they doubt implies that there is a doubter. Spinoza derived a rationalist system in which there is only one substance, God. Leibniz derived a system in which there are an infinite number of substances, his Monads.

Empiricism

Empiricists claim knowledge is a product of human experience. Statements of observations take pride of place in empiricist theory. Naïve empiricism holds simply that our ideas and theories need to be tested against reality, and accepted or rejected on the basis of how well they correspond to the facts. The central problem for epistemology then becomes explaining this correspondence.

Empiricism is associated with science. While there can be little doubt about the effectiveness of science, there is much philosophical debate about how and why science works. The Scientific Method was once favoured as the reason for scientific success, but recently difficulties in the philosophy of science have led to a rise in Coherentism.

Empiricism is often confused with positivism, which places higher emphasis on ideas about reality than on experiences with reality themselves.

Naïve realism

Naïve realism, or Common-Sense realism is the belief that there is a real external world, and that our perceptions are caused directly by that world. It has its foundation in causation in that an object being there causes us to see it. Thus, it follows, the world remains as it is when it is perceived - when it is not being perceived - a room is still there once we exit. The opposite theory to this is solipsism. Naïve realism fails to take into account the psychology of perception.

Objectivism

Objectivism, the epistemological theory of Ayn Rand, is similar to Naïve realism in that there is an external world, of which we gain knowledge through the senses. Objectivism holds that raw sense data is automatically integrated by the brain into percepts of entities (or objects), and that it is the function of consciousness to perceive reality, not create, invent, or alter it in any way. Once we recognize that two entities are similar to one another, and different from other objects, we are able to view them as two of the same kind of thing and form a concept which integrates all entities of that particular kind, enabling consciousness to cognitively deal with a potentially unlimited number of existents by means of a single, directly perceivable word. Objectivism rejects pure empiricism on the grounds that we are able to move beyond the level of sense-perceptions by means of objective concepts. It also rejects pure representationalism and idealism on the grounds that what we perceive is reality, and that it is meaningless to speak of a non-perceptual knowledge of reality, because percepts are our only means of gaining knowledge of reality.

Representationalism

Representationalism or Representative realism, unlike Naïve Realism, proposes that we cannot see the external world directly, but only through our perceptual representations of it. In other words, the objects and the world that you see around you are not the world itself, but merely an internal virtual-reality replica of that world. The so-called veil of perception removes the real world from our direct inspection.

Idealism

Idealism holds that what we refer to and perceive as the external world is in some way an artifice of the mind. Analytic statements (for example, mathematical truths), are held to be true without reference to the external world, and these are taken to be exemplary knowledge statements. George Berkeley, Immanuel Kant and Georg Hegel held various idealist views.

Phenomenalism

Phenomenalism is a development from George Berkeley's claim that to be is to be perceived. According to phenomenalism, when you see "a tree" you see a certain perception of a brown shape. On this view, one shouldn't think of objects as distinct substances, which interact with our senses so that we may perceive them; rather we should conclude that all that really exists is the perception itself.

Nowadays this point of view is rejected as solipsism, the fallacious argument that maybe all that really exists is perception, because there is no proof this hypothesis is false, which is the logical fallacy of argment _ad ignorantiam_).

Contemporary approaches

Much contemporary work in epistemology depends on the two categories: foundationalism and coherentism.

Recently, Susan Haack has attempted to fuse these two approaches into her doctrine of Foundherentism, which accrues degrees of relative confidence to beliefs by mediating between the two approaches. She covers this in her book Evidence and Inquiry: Towards Reconstruction in Epistemology.

Reliabilism involves making predictions from what usually happens (e.g. claiming to speak Russian can be proved by a Russian speaker). There are two methods of reliable justification: External (Reliable, e.g. a doctor diagnosing me); and Internal (Unreliable, e.g. relying on sensations from my internal organs). But how do we know that something that is reliable is right? A computer program with a bug in it is reliably incorrect.

In the aftermath of the publication of the Gettier problem and other similar scenarios, a number of new definitions were formulated. While there is general consensus that truth and belief are two necessary facets of knowledge, there is a debate about what needs to be added to the true beliefs to make them knowledge, and a debate about whether justification is necessary in the definition at all.

Some examples of these new definitions include (where S is the belief holder and p is the belief):

  • ‘Applicable Knowledge’, attributed to Zacharyas Boufoy-Bastick, states that " S can know p if and only if p is true, and S is pragmatically justified in believing p.
    • This is a development in Epistemology, attained through merging Foundationism and Coherentism, which supposes that “the acceptance of belief as knowledge lies in observable and practical use”. Within the context of this theory, since an element cannot be shown to belong to the widest-possible system of beliefs, foundational knowledge is unattainable. From this clause, ‘Applicable Knowledge’ states that one must be satisfied with something less than Foundationism-based absolute knowledge and, hence, that the ‘pragmatic’ condition be added to the tripartite definition of knowledge.
  • Peter Unger's "No accident account of knowledge", which defines knowledge as "S knows p if and only if it is not at all accidental that S's belief in p is true".
  • The "Defeasibilty account of knowledge", where "There is no other proposition (q), such that if S became justified in q, S would no longer be justified in p". Under this account, q is known as the "defeater".
  • The "Causational Account", where "The fact of p causes S's belief in p"
    • A problem with the Causational account is that deviant causal chains can emerge. Philosopher Alvin Goldman added that "Fact that p, causes fact that q, causes S's belief in q is not knowledge, but belief in q, from which p is inferred, is knowledge". However, there must be an awareness of the causal chain.
  • The Conditional Account associated with Robert Nozick. S believes in p, p is the case, and if p were not the case, then S would not believe it.
  • The "Reliable Analysis" account, which adds to the "justified true belief" definition that "S arrived at p by a reliable method, or S is a reliable judge in such matters".

Gettier

The problems show that there are situations in which a belief may be justified and true, and would not be knowledge. Although being a justified, true belief is necessary for a definition of knowledge, it is not sufficient. At the least, the set of our justified true beliefs contains things that we would not say that we know.

Some epistemologists have attempted to find strengthened criteria for knowledge that are not subject to the sorts of counterexamples Gettier and his many successors have produced. Most of these attempts involve adding a fourth condition or placing restrictions on the kind or degree of justification suitable to produce knowledge. None of these projects has yet gained widespread acceptance. Kirkham has argued that this is because the only definition that could ever be immune to all such counterexamples is the original one that prevailed from ancient times through Russell: to qualify as an item of knowledge, a belief must not only be true and justified, the evidence for the belief must necessitate its truth. But this conclusion is generally resisted since it easily appears to entail a sweeping skepticism.

Epistemic theories

Epistemic philosophers

Related topics

External links and references

Categories: