Coherentism
Encyclopedia
There are two distinct types of coherentism. One refers to the coherence theory of truth
. The other refers to the coherence theory of justification
. The coherentist theory of justification characterizes epistemic justification as a property of a belief only if that belief is a member of a coherent set. What distinguishes coherentism from other theories of justification is that the set is the primary bearer of justification. As an epistemological theory
, coherentism opposes foundationalism
and infinitism
and attempts to offer a solution to the regress argument. In this epistemological capacity, it is a theory about how belief
can be justified
.
Coherentism is a view about the structure of justification or knowledge. The coherentist's thesis is normally formulated in terms of a denial of its contrary foundationalism. Coherentism thus claims, minimally, that not all knowledge and justified belief rest ultimately on a foundation of noninferential knowledge or justified belief.
This negative construal of coherentism occurs because of the prominence of the regress problem in the history of epistemology, and the long-held assumption that only foundationalism provides an adequate, non-skeptical solution to that problem. After responding to the regress problem by denying foundationalism, coherentists normally characterize their view positively by replacing the foundationalism metaphor of a building as a model for the structure of knowledge with different metaphors, such as the metaphor which models our knowledge on a ship at sea whose seaworthiness must be ensured by repairs to any part in need of it. Coherentists typically hold that justification is solely a function of some relationship between beliefs, none of which are privileged beliefs in the way maintained by foundationalists, with different varieties of coherentism individuated by the specific relationship among beliefs identified as coherence.
, coherentism restricts true sentences to those that cohere with some specified set of sentences. Someone's belief is true if and only if it is coherent with all or most of his or her other beliefs. Usually, coherence is taken to imply something stronger than mere consistency. Statements that are comprehensive and meet the requirements of Occam's razor
are usually to be preferred.
As an illustration of the principle, if people lived in a virtual reality
universe, they could see birds in the trees that aren't really there. Not only are the birds not really there, but the trees aren't really there either. The people know that the bird and the tree are there, because it coheres with the rest of their experiences in the virtual reality. Talking about coherence is an abstract way of talking about the things that the people really know, without regard for whether they are in a virtual reality or not.
Perhaps the best-known objection to a coherence theory of truth is Bertrand Russell
's. Russell maintained that since both a belief and its negation
will, individually, cohere with at least one set of beliefs, this means that contradictory beliefs can be shown to be true according to coherence theory, and therefore that the theory cannot work. However, what most coherence theorists are concerned with is not all possible beliefs, but the set of beliefs that people actually hold. The main problem for a coherence theory of truth, then, is how to specify just this particular set, given that the truth of which beliefs are actually held can only be determined by means of coherence.
P, it appears reasonable to ask for a justification for P. If that justification takes the form of another statement, P', one can again reasonably ask for a justification for P', and so forth. There are three possible outcomes to this questioning process:
An infinite series appears to offer little help, since it is basically impossible to check that each justification is satisfactory. Relying on such a series quickly leads to skepticism
.
A loop begs the question
. Coherentism is sometimes characterised as accepting that the series forms a loop, but although this would produce a form of coherentism, this is not what is generally meant by the term.
. For instance, rationalists such as Descartes
and Spinoza
developed axiomatic system
s that relied on statements that were taken to be self-evident: "I think therefore I am" is the most famous example. Similarly, empiricists take observations as providing the foundation for the series.
Foundationalism relies on the claim that it is not necessary to ask for justification of certain propositions, or that they are self-justifying. If someone makes an observational statement, such as "it is raining", it does seem reasonable to ask how they know—did they look out the window? Did someone else tell them? Did they just come in shaking their umbrella? Coherentism insists that it is always reasonable to ask for a justification for any statement. Coherentism contends that foundationalism provides an arbitrary spot to stop asking for justification and so that it does not provide reasons to think that certain beliefs do not need justification.
has expressed the same point differently, arguing that beliefs must be "mutually consistent, cotenable, and supportive. That is, the components must be reasonable in light of one another. Since both cotenability and supportiveness are matters of degree, coherence is too." Usually the system of belief is taken to be the complete set of beliefs of the individual or group, that is, their theory of the world.
It is necessary for coherentism to explain in some detail what it means for a system to be coherent. At the least, coherence must include logical consistency. It also usually requires some degree of integration of the various components of the system. A system that contains more than one unrelated explanation of the same phenomenon is not as coherent as one that uses only one explanation, all other things being equal. Conversely, a theory that explains divergent phenomena using unrelated explanations is not as coherent as one that uses only one explanation for those divergent phenomena. These requirements are variations on Occams razor. The same points can be made more formally using Bayesian statistics
. Finally, the greater the number of phenomena explained by the system, the greater its coherence.
. This states that there is no obvious way in which a coherent system relates to anything that might exist outside of it. So, it may be possible to construct a coherent theory of the world, which does not correspond to what actually occurs in the world. In other words, it appears to be entirely possible to develop a system that is entirely coherent and yet entirely untrue.
It is surprisingly difficult to even state the problem from the point of view of a coherentist, because the phrase correspond to reality has a different meaning in a coherentist system. For a coherentist, reality is exactly the entire coherent system. It is simply not possible for a coherent theory not to correspond to reality, if reality is the very same thing as the entire coherent system. However, coherentists need to account for propositions which report observations, such as: "I believe it is raining because I looked out of the window and saw it was raining".
Put another way, coherentists might reply to the critic that any substantial system that was not true would by definition contain some contradictions, and so be incoherent.
This should become clear by looking at the differences between a coherentist and correspondence account of a scientific advance. Newtonian mechanics was shown to be inconsistent with certain experiments, notably the Michelson-Morley experiment
. The theory used by physicists was thereafter changed from Newtonian to relativistic mechanics
.
One who held to a correspondence theory might say that there was an apparent lack of correspondence between the model (physics
) and reality
, and that the model was altered in order that it correspond to the observed facts.
A coherentist account might claim that before the Michelson-Morley experiment, physics formed a coherent theory. But then the experiment was performed. These experimental results form a part of the account, yet the results were inconsistent with the expectations of the accepted theory. Thus the account was shown to be less coherent. This inconsistency was resolved by the development of relativistic mechanics. In this case a coherentist would need to explain how special relativity
is more coherent than both Newtonian mechanics and the Lorentz ether theory
, which explanation would lead us on from simple inconsistency.
Any lack of correspondence of the theory with reality may eventually lead to a lack of coherence within the theory, and this leads to a modification of the theory to restore its coherence. There would be little or no practical difference between a coherentist account and a correspondence account of theory change.
Another problem coherentism has to face is the plurality objection. There is nothing within the definition of coherence which makes it impossible for two entirely different sets of beliefs to be internally coherent. Thus there might be several such sets. But if one supposes—in line with the principle of non-contradiction—that there can only be one complete set of truths, coherentism must provide a way to choose between these competing sets.
Coherence theory of truth
Coherence theory of truth regards truth as coherence with some specified set of sentences, propositions or beliefs. There is no single coherence theory of truth, but rather an assortment of perspectives that are commonly collected under this title...
. The other refers to the coherence theory of justification
Theory of justification
Theory of justification is a part of epistemology that attempts to understand the justification of propositions and beliefs. Epistemologists are concerned with various epistemic features of belief, which include the ideas of justification, warrant, rationality, and probability...
. The coherentist theory of justification characterizes epistemic justification as a property of a belief only if that belief is a member of a coherent set. What distinguishes coherentism from other theories of justification is that the set is the primary bearer of justification. As an epistemological theory
Theory
The English word theory was derived from a technical term in Ancient Greek philosophy. The word theoria, , meant "a looking at, viewing, beholding", and referring to contemplation or speculation, as opposed to action...
, coherentism opposes foundationalism
Foundationalism
Foundationalism is any theory in epistemology that holds that beliefs are justified based on what are called basic beliefs . This position is intended to resolve the infinite regress problem in epistemology...
and infinitism
Infinitism
Infinitism is the view that knowledge may be justified by an infinite chain of reasons. It belongs to epistemology, the branch of philosophy that considers the possibility, nature, and means of knowledge.-Epistemological infinitism:...
and attempts to offer a solution to the regress argument. In this epistemological capacity, it is a theory about how belief
Belief
Belief is the psychological state in which an individual holds a proposition or premise to be true.-Belief, knowledge and epistemology:The terms belief and knowledge are used differently in philosophy....
can be justified
Theory of justification
Theory of justification is a part of epistemology that attempts to understand the justification of propositions and beliefs. Epistemologists are concerned with various epistemic features of belief, which include the ideas of justification, warrant, rationality, and probability...
.
Coherentism is a view about the structure of justification or knowledge. The coherentist's thesis is normally formulated in terms of a denial of its contrary foundationalism. Coherentism thus claims, minimally, that not all knowledge and justified belief rest ultimately on a foundation of noninferential knowledge or justified belief.
This negative construal of coherentism occurs because of the prominence of the regress problem in the history of epistemology, and the long-held assumption that only foundationalism provides an adequate, non-skeptical solution to that problem. After responding to the regress problem by denying foundationalism, coherentists normally characterize their view positively by replacing the foundationalism metaphor of a building as a model for the structure of knowledge with different metaphors, such as the metaphor which models our knowledge on a ship at sea whose seaworthiness must be ensured by repairs to any part in need of it. Coherentists typically hold that justification is solely a function of some relationship between beliefs, none of which are privileged beliefs in the way maintained by foundationalists, with different varieties of coherentism individuated by the specific relationship among beliefs identified as coherence.
Definition
As a theory of truthTruth
Truth has a variety of meanings, such as the state of being in accord with fact or reality. It can also mean having fidelity to an original or to a standard or ideal. In a common usage, it also means constancy or sincerity in action or character...
, coherentism restricts true sentences to those that cohere with some specified set of sentences. Someone's belief is true if and only if it is coherent with all or most of his or her other beliefs. Usually, coherence is taken to imply something stronger than mere consistency. Statements that are comprehensive and meet the requirements of Occam's razor
Occam's razor
Occam's razor, also known as Ockham's razor, and sometimes expressed in Latin as lex parsimoniae , is a principle that generally recommends from among competing hypotheses selecting the one that makes the fewest new assumptions.-Overview:The principle is often summarized as "simpler explanations...
are usually to be preferred.
As an illustration of the principle, if people lived in a virtual reality
Virtual reality
Virtual reality , also known as virtuality, is a term that applies to computer-simulated environments that can simulate physical presence in places in the real world, as well as in imaginary worlds...
universe, they could see birds in the trees that aren't really there. Not only are the birds not really there, but the trees aren't really there either. The people know that the bird and the tree are there, because it coheres with the rest of their experiences in the virtual reality. Talking about coherence is an abstract way of talking about the things that the people really know, without regard for whether they are in a virtual reality or not.
Perhaps the best-known objection to a coherence theory of truth is Bertrand Russell
Bertrand Russell
Bertrand Arthur William Russell, 3rd Earl Russell, OM, FRS was a British philosopher, logician, mathematician, historian, and social critic. At various points in his life he considered himself a liberal, a socialist, and a pacifist, but he also admitted that he had never been any of these things...
's. Russell maintained that since both a belief and its negation
Negation
In logic and mathematics, negation, also called logical complement, is an operation on propositions, truth values, or semantic values more generally. Intuitively, the negation of a proposition is true when that proposition is false, and vice versa. In classical logic negation is normally identified...
will, individually, cohere with at least one set of beliefs, this means that contradictory beliefs can be shown to be true according to coherence theory, and therefore that the theory cannot work. However, what most coherence theorists are concerned with is not all possible beliefs, but the set of beliefs that people actually hold. The main problem for a coherence theory of truth, then, is how to specify just this particular set, given that the truth of which beliefs are actually held can only be determined by means of coherence.
The regress argument
Both coherence and foundationalist theories of justification attempt to answer the regress argument, a fundamental problem in epistemology that goes as follows. Given some statementStatement
Statement may refer to:* A kind of expression in language *Statement , declarative sentence that is either true or false*Statement , the smallest standalone element of an imperative programming language...
P, it appears reasonable to ask for a justification for P. If that justification takes the form of another statement, P', one can again reasonably ask for a justification for P', and so forth. There are three possible outcomes to this questioning process:
- the series is infinitely long, with every statement justified by some other statement.
- the series forms a loop, so that each statement is ultimately involved in its own justification.
- the series terminates with certain statements having to be self justifying.
An infinite series appears to offer little help, since it is basically impossible to check that each justification is satisfactory. Relying on such a series quickly leads to skepticism
Skepticism
Skepticism has many definitions, but generally refers to any questioning attitude towards knowledge, facts, or opinions/beliefs stated as facts, or doubt regarding claims that are taken for granted elsewhere...
.
A loop begs the question
Begging the question
Begging the question is a type of logical fallacy in which the proposition to be proven is assumed implicitly or explicitly in the premise....
. Coherentism is sometimes characterised as accepting that the series forms a loop, but although this would produce a form of coherentism, this is not what is generally meant by the term.
Foundationalism's response
One might conclude that there must be some statements that, for some reason, do not need justification. This view is called foundationalismFoundationalism
Foundationalism is any theory in epistemology that holds that beliefs are justified based on what are called basic beliefs . This position is intended to resolve the infinite regress problem in epistemology...
. For instance, rationalists such as Descartes
René Descartes
René Descartes ; was a French philosopher and writer who spent most of his adult life in the Dutch Republic. He has been dubbed the 'Father of Modern Philosophy', and much subsequent Western philosophy is a response to his writings, which are studied closely to this day...
and Spinoza
Baruch Spinoza
Baruch de Spinoza and later Benedict de Spinoza was a Dutch Jewish philosopher. Revealing considerable scientific aptitude, the breadth and importance of Spinoza's work was not fully realized until years after his death...
developed axiomatic system
Axiomatic system
In mathematics, an axiomatic system is any set of axioms from which some or all axioms can be used in conjunction to logically derive theorems. A mathematical theory consists of an axiomatic system and all its derived theorems...
s that relied on statements that were taken to be self-evident: "I think therefore I am" is the most famous example. Similarly, empiricists take observations as providing the foundation for the series.
Foundationalism relies on the claim that it is not necessary to ask for justification of certain propositions, or that they are self-justifying. If someone makes an observational statement, such as "it is raining", it does seem reasonable to ask how they know—did they look out the window? Did someone else tell them? Did they just come in shaking their umbrella? Coherentism insists that it is always reasonable to ask for a justification for any statement. Coherentism contends that foundationalism provides an arbitrary spot to stop asking for justification and so that it does not provide reasons to think that certain beliefs do not need justification.
Coherentism's response
Coherentism denies the soundness of the regression argument. The regression argument makes the assumption that the justification for a proposition takes the form of another proposition: P" justifies P', which in turn justifies P. For coherentism, justification is a holistic process. Inferential justification for the belief that P is nonlinear. This means that P" and P' are not epistemically prior to P. Rather, the beliefs that P", P', and P work together to achieve epistemic justification. Catherine ElginCatherine Elgin
Catherine Elgin is a philosopher whose focus is the theory of knowledge and the philosophies of art and science. She holds a Ph.D. from Brandeis University and is currently a professor at Harvard University...
has expressed the same point differently, arguing that beliefs must be "mutually consistent, cotenable, and supportive. That is, the components must be reasonable in light of one another. Since both cotenability and supportiveness are matters of degree, coherence is too." Usually the system of belief is taken to be the complete set of beliefs of the individual or group, that is, their theory of the world.
It is necessary for coherentism to explain in some detail what it means for a system to be coherent. At the least, coherence must include logical consistency. It also usually requires some degree of integration of the various components of the system. A system that contains more than one unrelated explanation of the same phenomenon is not as coherent as one that uses only one explanation, all other things being equal. Conversely, a theory that explains divergent phenomena using unrelated explanations is not as coherent as one that uses only one explanation for those divergent phenomena. These requirements are variations on Occams razor. The same points can be made more formally using Bayesian statistics
Bayesian statistics
Bayesian statistics is that subset of the entire field of statistics in which the evidence about the true state of the world is expressed in terms of degrees of belief or, more specifically, Bayesian probabilities...
. Finally, the greater the number of phenomena explained by the system, the greater its coherence.
Difficulties for coherentism
The main criticism facing coherentism, the isolation objection, is probably simplest to state from the point of view of someone who holds to the correspondence theory of truthCorrespondence theory of truth
The correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world, and whether it accurately describes that world...
. This states that there is no obvious way in which a coherent system relates to anything that might exist outside of it. So, it may be possible to construct a coherent theory of the world, which does not correspond to what actually occurs in the world. In other words, it appears to be entirely possible to develop a system that is entirely coherent and yet entirely untrue.
It is surprisingly difficult to even state the problem from the point of view of a coherentist, because the phrase correspond to reality has a different meaning in a coherentist system. For a coherentist, reality is exactly the entire coherent system. It is simply not possible for a coherent theory not to correspond to reality, if reality is the very same thing as the entire coherent system. However, coherentists need to account for propositions which report observations, such as: "I believe it is raining because I looked out of the window and saw it was raining".
Put another way, coherentists might reply to the critic that any substantial system that was not true would by definition contain some contradictions, and so be incoherent.
This should become clear by looking at the differences between a coherentist and correspondence account of a scientific advance. Newtonian mechanics was shown to be inconsistent with certain experiments, notably the Michelson-Morley experiment
Michelson-Morley experiment
The Michelson–Morley experiment was performed in 1887 by Albert Michelson and Edward Morley at what is now Case Western Reserve University in Cleveland, Ohio. Its results are generally considered to be the first strong evidence against the theory of a luminiferous ether and in favor of special...
. The theory used by physicists was thereafter changed from Newtonian to relativistic mechanics
Theory of relativity
The theory of relativity, or simply relativity, encompasses two theories of Albert Einstein: special relativity and general relativity. However, the word relativity is sometimes used in reference to Galilean invariance....
.
One who held to a correspondence theory might say that there was an apparent lack of correspondence between the model (physics
Physics
Physics is a natural science that involves the study of matter and its motion through spacetime, along with related concepts such as energy and force. More broadly, it is the general analysis of nature, conducted in order to understand how the universe behaves.Physics is one of the oldest academic...
) and reality
Reality
In philosophy, reality is the state of things as they actually exist, rather than as they may appear or might be imagined. In a wider definition, reality includes everything that is and has been, whether or not it is observable or comprehensible...
, and that the model was altered in order that it correspond to the observed facts.
A coherentist account might claim that before the Michelson-Morley experiment, physics formed a coherent theory. But then the experiment was performed. These experimental results form a part of the account, yet the results were inconsistent with the expectations of the accepted theory. Thus the account was shown to be less coherent. This inconsistency was resolved by the development of relativistic mechanics. In this case a coherentist would need to explain how special relativity
Special relativity
Special relativity is the physical theory of measurement in an inertial frame of reference proposed in 1905 by Albert Einstein in the paper "On the Electrodynamics of Moving Bodies".It generalizes Galileo's...
is more coherent than both Newtonian mechanics and the Lorentz ether theory
Lorentz ether theory
What is now often called Lorentz Ether theory has its roots in Hendrik Lorentz's "Theory of electrons", which was the final point in the development of the classical aether theories at the end of the 19th and at the beginning of the 20th century....
, which explanation would lead us on from simple inconsistency.
Any lack of correspondence of the theory with reality may eventually lead to a lack of coherence within the theory, and this leads to a modification of the theory to restore its coherence. There would be little or no practical difference between a coherentist account and a correspondence account of theory change.
Another problem coherentism has to face is the plurality objection. There is nothing within the definition of coherence which makes it impossible for two entirely different sets of beliefs to be internally coherent. Thus there might be several such sets. But if one supposes—in line with the principle of non-contradiction—that there can only be one complete set of truths, coherentism must provide a way to choose between these competing sets.
Theories of truth
- Consensus theory of truthConsensus theory of truthA consensus theory of truth is any theory of truth that refers to a concept of consensus as a part of its concept of truth.-Consensus gentium:...
- Correspondence theory of truthCorrespondence theory of truthThe correspondence theory of truth states that the truth or falsity of a statement is determined only by how it relates to the world, and whether it accurately describes that world...
- Deflationary theory of truthDeflationary theory of truthA deflationary theory of truth is one of a family of theories which all have in common the claim that assertions that predicate truth of a statement do not attribute a property called truth to such a statement.-Redundancy theory:...
- Epistemic theories of truthEpistemic theories of truthIn philosophy, epistemic theories of truth are attempts to analyze the notion of truth in terms of epistemic notions such as knowledge, belief, acceptance, verification, justification, and perspective....
- Indefinability theory of truth
- Pragmatic theory of truthPragmatic theory of truthPragmatic theory of truth refers to those accounts, definitions, and theories of the concept truth that distinguish the philosophies of pragmatism and pragmaticism...
- Redundancy theory of truthRedundancy theory of truthAccording to the redundancy theory of truth, or the disquotational theory of truth, asserting that a statement is true is completely equivalent to asserting the statement itself. For example, asserting the sentence " 'Snow is white' is true" is equivalent to asserting the sentence "Snow is...
- Semantic theory of truthSemantic theory of truthA semantic theory of truth is a theory of truth in the philosophy of language which holds that truth is a property of sentences.-Origin:The semantic conception of truth, which is related in different ways to both the correspondence and deflationary conceptions, is due to work published by Polish...