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Truth can have a variety of meanings, from the state of being the case, being in accord with a particular fact or reality, being in accord with the body of real things, events, actuality, or fidelity to an original or to a standard. In archaic usage it could be fidelity, constancy or sincerity in action, character, and utterance. The term has no single definition yet about which over fifty percent of professional philosophers and scholars agree, and various theories and views of truth continue to be debated. There are differing claims on such questions as what constitutes truth; what things are truthbearers capable of being true or false; how to define and identify truth; the roles that revealed and acquired knowledge play; and whether truth is subjective, relative, objective, or absolute. This article introduces the various perspectives and claims, both today and throughout history.
Nomenclature and etymology
The English word truth is from Old English tríewþ, tréowþ, trýwþ, Middle English trewþe, cognate to Old High German triuwida, Old Norse tryggð. Like troth, it is a -th nominalisation of the adjective true (Old English tréowe).
The English word true is from Old English (West Saxon) (ge)tríewe, tréowe, cognate to Old Saxon (gi)trûui, Old High German (ga)triuwu (Modern German treu "faithful"), Old Norse tryggr, Gothic triggws, all from a Proto-Germanic *trewwj- "having good faith". Old Norse trú, "faith, word of honour; religious faith, belief" (archaic English troth "loyalty, honesty, good faith", compare Ásatrú).
All Germanic languages besides English have introduced a terminological distinction between truth "fidelity" and truth "factuality". To express "factuality", North Germanic opted for nouns derived from sanna "to assert, affirm", while continental West Germanic (German and Dutch) opted for continuations of wâra "faith, trust, pact" (cognate to Slavic věra "(religious) faith", but influenced by Latin verus). Romance languages use terms following the Latin veritas, while the Greek aletheia and Slavic pravda have separate etymological origins.
The major theories of truth
The question of what is a proper basis for deciding how words, symbols, ideas and beliefs may properly be considered true, whether by a single person or an entire society, is dealt with by the five major substantive theories introduced below. Each theory presents perspectives that are widely shared by published scholars. There also have more recently arisen "deflationary" or "minimalist" theories of truth based on the idea that the application of a term like true to a statement does not assert anything significant about it, for instance, anything about its nature, but that the label truth is a tool of discourse used to express agreement, to emphasize claims, or to form certain types of generalizations.
Bold text'''Bold text''Italic text'Italic text'Italic text''Italic text''''Bold text''''Bold text'Bold text''''''''''''''''''====Correspondence theory====
- Main article: Correspondence theory of truth
For the truth to correspond it must first be proved by evidence or an individuals valid opinion, which have similar meaning or context. This type of theory posits a relationship between thoughts or statements on the one hand, and things or objects on the other. It is a traditional model which goes back at least to some of the classical Greek philosophers such as Socrates, Plato, and Aristotle. This class of theories holds that the truth or the falsity of a representation is determined in principle solely by how it relates to "things", by whether it accurately describes those "things". An example of correspondence theory is the statement by the Thirteenth Century philosopher/theologian Thomas Aquinas: Veritas est adaequatio rei et intellectus ("Truth is the equation [or adequation] of things and intellect"), a statement which Aquinas attributed to the Ninth Century neoplatonist Isaac Israeli. Aquinas also restated the theory as: “A judgment is said to be true when it conforms to the external reality” 
Correspondence theory practically operates on the assumption that truth is a matter of accurately copying what was much later called "objective reality" and then representing it in thoughts, words and other symbols. Many modern theorists have stated that this ideal cannot be achieved independently of some analysis of additional factors. For example, language plays a role in that all languages have words that are not easily translatable into another. The German word Zeitgeist is one such example: one who speaks or understands the language may "know" what it means, but any translation of the word fails to accurately capture its full meaning (this is a problem with many abstract words, especially those derived in agglutinative languages). Thus, some words add an additional parameter to the construction of an accurate truth predicate. Among the philosophers who grappled with this problem is Alfred Tarski, whose semantic theory is summarized further below in this article.
Proponents of several of the theories below have gone further to assert that there are yet other issues necessary to the analysis, such as interpersonal power struggles, community interactions, personal biases and other factors involved in deciding what is seen as truth.
- Main article: Coherence theory of truth
For coherence theories in general, truth requires a proper fit of elements within a whole system. Very often, though, coherence is taken to imply something more than simple logical consistency; often there is a demand that the propositions in a coherent system lend mutual inferential support to each other. So, for example, the completeness and comprehensiveness of the underlying set of concepts is a critical factor in judging the validity and usefulness of a coherent system. A pervasive tenet of coherence theories is the idea that truth is primarily a property of whole systems of propositions, and can be ascribed to individual propositions only according to their coherence with the whole. Among the assortment of perspectives commonly regarded as coherence theory, theorists differ on the question of whether coherence entails many possible true systems of thought or only a single absolute system.
Some variants of coherence theory are claimed to characterize the essential and intrinsic properties of formal systems in logic and mathematics. However, formal reasoners are content to contemplate axiomatically independent and sometimes mutually contradictory systems side by side, for example, the various alternative geometries. On the whole, coherence theories have been criticized as lacking justification in their application to other areas of truth, especially with respect to assertions about the natural world, empirical data in general, assertions about practical matters of psychology and society, especially when used without support from the other major theories of truth.
Coherence theories distinguish the thought of rationalist philosophers, particularly of Spinoza, Leibniz, and G.W.F. Hegel, along with the British philosopher F.H. Bradley. They have found a resurgence also among several proponents of logical positivism, notably Otto Neurath and Carl Hempel.
- Main article: Constructivist epistemology
Social constructivism holds that truth is constructed by social processes, is historically and culturally specific, and that it is in part shaped through the power struggles within a community. Constructivism views all of our knowledge as "constructed," because it does not reflect any external "transcendent" realities (as a pure correspondence theory might hold). Rather, perceptions of truth are viewed as contingent on convention, human perception, and social experience. It is believed by constructivists that representations of physical and biological reality, including race, sexuality, and gender are socially constructed.
Giambattista Vico was among the first to claim that history and culture were man-made. Vico's epistemological orientation gathers the most diverse rays and unfolds in one axiom – verum ipsum factum – "truth itself is constructed". Hegel and Marx were among the other early proponents of the premise that truth is, or can be, socially constructed. Marx, like many critical theorists who followed, did not reject the existence of objective truth but rather distinguished between true knowledge and knowledge that has been distorted through power or ideology. For Marx scientific and true knowledge is 'in accordance with the dialectical understanding of history' and ideological knowledge 'an epiphenomenal expression of the relation of material forces in a given economic arrangement'.
- Main article: Consensus theory of truth
Consensus theory holds that truth is whatever is agreed upon, or in some versions, might come to be agreed upon, by some specified group. Such a group might include all human beings, or a subset thereof consisting of more than one person.
Among the current advocates of consensus theory as a useful accounting of the concept of "truth" is the philosopher Jürgen Habermas. Habermas maintains that truth is what would be agreed upon in an ideal speech situation. Among the current strong critics of consensus theory is the philosopher Nicholas Rescher.
- Main article: Pragmatic theory of truth
The three most influential forms of the pragmatic theory of truth were introduced around the turn of the 20th century by Charles Sanders Peirce, William James, and John Dewey. Although there are wide differences in viewpoint among these and other proponents of pragmatic theory, they hold in common that truth is verified and confirmed by the results of putting one's concepts into practice.
Peirce defines truth as follows: "Truth is that concordance of an abstract statement with the ideal limit towards which endless investigation would tend to bring scientific belief, which concordance the abstract statement may possess by virtue of the confession of its inaccuracy and one-sidedness, and this confession is an essential ingredient of truth." This statement emphasizes Peirce's view that ideas of approximation, incompleteness, and partiality, what he describes elsewhere as fallibilism and "reference to the future", are essential to a proper conception of truth. Although Peirce uses words like concordance and correspondence to describe one aspect of the pragmatic sign relation, he is also quite explicit in saying that definitions of truth based on mere correspondence are no more than nominal definitions, which he accords a lower status than real definitions.
William James's version of pragmatic theory, while complex, is often summarized by his statement that "the 'true' is only the expedient in our way of thinking, just as the 'right' is only the expedient in our way of behaving." By this, James meant that truth is a quality the value of which is confirmed by its effectiveness when applying concepts to actual practice (thus, "pragmatic").
John Dewey, less broadly than James but more broadly than Peirce, held that inquiry, whether scientific, technical, sociological, philosophical or cultural, is self-corrective over time if openly submitted for testing by a community of inquirers in order to clarify, justify, refine and/or refute proposed truths.
Minimalist (deflationary) theories
- Main article: Deflationary theory of truth
A number of philosophers reject the thesis that the concept or term truth refers to a real property of sentences or propositions. These philosophers are responding, in part, to the common use of truth predicates (e.g., that some particular thing "...is true") which was particularly prevalent in philosophical discourse on truth in the first half of the 20th century. From this point of view, to assert the proposition “'2 + 2 = 4' is true” is logically equivalent to asserting the proposition “2 + 2 = 4”, and the phrase “is true” is completely dispensable in this and every other context. These positions are broadly described
- as deflationary theories of truth, since they attempt to deflate the presumed importance of the words "true" or truth,
- as disquotational theories, to draw attention to the disappearance of the quotation marks in cases like the above example, or
- as minimalist theories of truth.
Whichever term is used, deflationary theories can be said to hold in common that "[t]he predicate 'true' is an expressive convenience, not the name of a property requiring deep analysis." Once we have identified the truth predicate's formal features and utility, deflationists argue, we have said all there is to be said about truth. Among the theoretical concerns of these views is to explain away those special cases where it does appear that the concept of truth has peculiar and interesting properties. (See, e.g., Semantic paradoxes, and below.)
In addition to highlighting such formal aspects of the predicate "is true", some deflationists point out that the concept enables us to express things that might otherwise require infinitely long sentences. For example, one cannot express confidence in Michael's accuracy by asserting the endless sentence:
- Michael says, 'snow is white' and snow is white, or he says 'roses are red' and roses are red or he says ... etc.
This assertion can also be succinctly expressed by saying: What Michael says is true.
Performative theory of truth
Attributed to P. F. Strawson is the performative theory of truth which holds that to say "'Snow is white' is true" is to perform the speech act of signaling one's agreement with the claim that snow is white (much like nodding one's head in agreement). The idea that some statements are more actions than communicative statements is not as odd as it may seem. Consider, for example, that when the bride says "I do" at the appropriate time in a wedding, she is performing the act of taking this man to be her lawful wedded husband. She is not describing herself as taking this man, but actually doing so (perhaps the most thorough analysis of such "perlocutionary" statements is J. L. Austin, "How to Do Things With Words").
Strawson holds that a similar analysis is applicable to all speech acts, not only to special perlocutionary ones: "To say a statement is true is not to make a statement about a statement, but rather to perform the act of agreeing with, accepting, or endorsing a statement. When one says 'It's true that it's raining,' one asserts no more than 'It's raining.' The function of [the statement] 'It's true that...' is to agree with, accept, or endorse the statement that 'it's raining.'"
- Main article: Redundancy theory of truth
According to the redundancy theory of truth, asserting that a statement is true is completely equivalent to asserting the statement itself. For example, making the assertion that " 'Snow is white' is true" is equivalent to asserting "Snow is white". Redundancy theorists infer from this premise that truth is a redundant concept; that is, it is merely a word that is traditionally used in conversation or writing, generally for emphasis, but not a word that actually equates to anything in reality. This theory is commonly attributed to Frank P. Ramsey, who held that the use of words like fact and truth was nothing but a roundabout way of asserting a proposition, and that treating these words as separate problems in isolation from judgment was merely a "linguistic muddle".
A variant of redundancy theory is the disquotational theory which uses a modified form of Tarski's schema: To say that '"P" is true' is to say that P. Yet another version of deflationism is the prosentential theory of truth, first developed by Dorothy Grover, Joseph Camp, and Nuel Belnap as an elaboration of Ramsey's claims. They argue that sentences like "That's true", when said in response to "It's raining", are prosentences, expressions that merely repeat the content of other expressions. In the same way that it means the same as my dog in the sentence My dog was hungry, so I fed it, That's true is supposed to mean the same as It's raining — if you say the latter and I then say the former. These variations do not necessarily follow Ramsey in asserting that truth is not a property, but rather can be understood to say that, for instance, the assertion "P" may well involve a substantial truth, and the theorists in this case are minimalizing only the redundancy or prosentence involved in the statement such as "that's true."
Deflationary principles do not apply to representations that are not analogous to sentences, and also do not apply to many other things that are commonly judged to be true or otherwise. Consider the analogy between the sentence "Snow is white" and the character named Snow White, both of which can be true in some sense. To a minimalist, saying "Snow is white is true" is the same as saying "Snow is white," but to say "Snow White is true" is not the same as saying "Snow White."
- Main article: Pluralist theories of truth
Several of the major theories of truth hold that there is a particular property the having of which makes a belief or proposition true. Pluralist theories of truth assert that there may be more than one property that makes propositions true: ethical propositions might be true by virtue of coherence. Propositions about the physical world might be true by corresponding to the objects and properties they are about.
Some of the pragmatic theories, such as those by Charles Peirce and William James, included aspects of correspondence, coherence and constructivist theories. Crispin Wright argued in his 1992 book Truth and Objectivity that any predicate which satisfied certain platitudes about truth qualified as a truth predicate. In some discourses, Wright argued, the role of the truth predicate might be played by the notion of superassertibility. Michael Lynch, in a 2009 book Truth as One and Many, argued that we should see truth as a functional property capable of being multiply manifested in distinct properties like correspondence or coherence. 
Most believed theories
According to a survey of professional philosophers and others on their philosophical views which was carried out in November 2009 (taken by 3226 respondents, including 1803 philosophy faculty members and/or PhDs and 829 philosophy graduate students) 44.9% of respondents accept or lean towards correspondence theories, 20.7% accept or lean towards deflationary theories and 13.8% epistemic theories.
Truth in logic
- Main article: Logical truth
Logic is concerned with the patterns in reason that can help tell us if a proposition is true or not. However, logic does not deal with truth in the absolute sense, as for instance a metaphysician does. Logicians use formal languages to express the truths which they are concerned with, and as such there is only truth under some interpretation or truth within some logical system.
A logical truth (also called an analytic truth or a necessary truth) is a statement which is true in all possible worlds or under all possible interpretations, as contrasted to a fact (also called a synthetic claim or a contingency) which is only true in this world as it has historically unfolded. A proposition such as “If p and q, then p.” is considered to be logical truth because it is true because of the meaning of the symbols and words in it and not because of any facts of any particular world. They are such that they could not be untrue.
Truth in mathematics
- Main article: Model theory
Historically, with the nineteenth century development of Boolean algebra mathematical models of logic began to treat "truth", also represented as "T" or "1", as an arbitrary constant. "Falsity" is also an arbitrary constant, which can be represented as "F" or "0". In propositional logic, these symbols can be manipulated according to a set of axioms and rules of inference, often given in the form of truth tables.
In addition, from at least the time of Hilbert's program at the turn of the twentieth century to the proof of Gödel's theorem and the development of the Church-Turing thesis in the early part of that century, true statements in mathematics were generally assumed to be those statements which are provable in a formal axiomatic system.
The works of Kurt Gödel, Alan Turing, and others shook this assumption, with the development of statements that are true but cannot be proven within the system. Two examples of the latter can be found in Hilbert's problems. Work on Hilbert's 10th problem led in the late twentieth century to the construction of specific Diophantine equations for which it is undecidable whether they have a solution, or even if they do, whether they have a finite or infinite number of solutions. More fundamentally, Hilbert's first problem was on the continuum hypothesis. Gödel and Paul Cohen showed that this hypothesis cannot be proved or disproved using the standard axioms of set theory and a finite number of proof steps. In the view of some, then, it is equally reasonable to take either the continuum hypothesis or its negation as a new axiom.
Semantic theory of truth
The semantic theory of truth has as its general case for a given language:
- 'P' is true if and only if P
where 'P' is a reference to the sentence (the sentence's name), and P is just the sentence itself.
Logician and philosopher Alfred Tarski developed the theory for formal languages (such as formal logic). Here he restricted it in this way: no language could contain its own truth predicate, that is, the expression is true could only apply to sentences in some other language. The latter he called an object language, the language being talked about. (It may, in turn, have a truth predicate that can be applied to sentences in still another language.) The reason for his restriction was that languages that contain their own truth predicate will contain paradoxical sentences like the Liar: This sentence is not true. See The Liar paradox. As a result Tarski held that the semantic theory could not be applied to any natural language, such as English, because they contain their own truth predicates. Donald Davidson used it as the foundation of his truth-conditional semantics and linked it to radical interpretation in a form of coherentism.
Bertrand Russell is credited with noticing the existence of such paradoxes even in the best symbolic formalizations of mathematics in his day, in particular the paradox that came to be named after him, Russell's paradox. Russell and Whitehead attempted to solve these problems in Principia Mathematica by putting statements into a hierarchy of types, wherein a statement cannot refer to itself, but only to statements lower in the hierarchy. This in turn led to new orders of difficulty regarding the precise natures of types and the structures of conceptually possible type systems that have yet to be resolved to this day.
Kripke's theory of truth
Saul Kripke contends that a natural language can in fact contain its own truth predicate without giving rise to contradiction. He showed how to construct one as follows:
- Begin with a subset of sentences of a natural language that contains no occurrences of the expression "is true" (or "is false"). So The barn is big is included in the subset, but not " The barn is big is true", nor problematic sentences such as "This sentence is false".
- Define truth just for the sentences in that subset.
- Then extend the definition of truth to include sentences that predicate truth or falsity of one of the original subset of sentences. So "The barn is big is true" is now included, but not either "This sentence is false" nor "'The barn is big is true' is true".
- Next, define truth for all sentences that predicate truth or falsity of a member of the second set. Imagine this process repeated infinitely, so that truth is defined for The barn is big; then for "The barn is big is true"; then for "'The barn is big is true' is true", and so on.
Notice that truth never gets defined for sentences like This sentence is false, since it was not in the original subset and does not predicate truth of any sentence in the original or any subsequent set. In Kripke's terms, these are "ungrounded." Since these sentences are never assigned either truth or falsehood even if the process is carried out infinitely, Kripke's theory implies that some sentences are neither true nor false. This contradicts the Principle of bivalence: every sentence must be either true or false. Since this principle is a key premise in deriving the Liar paradox, the paradox is dissolved.
View of truth as somebody
Expressing the serious view of Christians, especially the Catholic Church, not limited to truth in matters of religion, Father John Corapi repeatedly states and is frequently quoted as stating (with minor variations in wording) that "The Truth is not a something. It is a Somebody. And His Name is Jesus Christ.” Christians cite the Gospel of John, in which Jesus Christ is quoted as telling Thomas the Apostle that "I am the way, the truth, and the life." The Catechism of the Catholic Church states that "God ... is the truth" and that "the whole of God's truth" is manifest in His son, Jesus Christ. "He is the Truth." [emphasis in original] Ancient Egyptians held "In a hymn to Amon-Re, the creator and sustainer of the world, Ma’at equates with truth: Thy Mother is Truth, O Amon!" In Zoroastrian theology, the angel Rashnu, who presides at the "ordeal court", is truth personified.  Islamic prophecy projects: "All glory will come after his advent. He will be the personification of Truth and Uprightness, as if Allah had descended from the Heaven." (Tazkira, Page 691)
The ancient Greek origins of the words "true" and "truth" have some consistent definitions throughout great spans of history that were often associated with topics of logic, geometry, mathematics, deduction, induction, and natural philosophy.
Socrates', Plato's and Aristotle's ideas about truth are commonly seen as consistent with correspondence theory. In his Metaphysics, Aristotle stated: “To say of what is that it is not, or of what is not that it is, is false, while to say of what is that it is, and of what is not that it is not, is true”. The Stanford Encyclopedia of Philosophy proceeds to say of Aristotle:
Aristotle sounds much more like a genuine correspondence theorist in the Categories (12b11, 14b14), where he talks of “underlying things” that make statements true and implies that these “things” (pragmata) are logically structured situations or facts (viz., his sitting, his not sitting). Most influential is his claim in De Interpretatione (16a3) that thoughts are “likenessess” (homoiosis) of things. Although he nowhere defines truth in terms of a thought's likeness to a thing or fact, it is clear that such a definition would fit well into his overall philosophy of mind.
Very similar statements can also be found in Plato (Cratylus 385b2, Sophist 263b).
What corresponds in the mind to what is outside it.
The truth of a thing is the property of the being of each thing which has been established in it.
However, this definition is merely a translation of the Latin translation from the Middle Ages. A modern translation of the original Arabic text states:
Truth is also said of the veridical belief in the existence [of something].
Following Avicenna, and also Augustine and Aristotle, Thomas Aquinas stated in his Disputed Questions on Truth:
A natural thing, being placed between two intellects, is called true insofar as it conforms to either. It is said to be true with respect to its conformity with the divine intellect insofar as it fulfills the end to which it was ordained by the divine intellect... With respect to its conformity with a human intellect, a thing is said to be true insofar as it is such as to cause a true estimate about itself.
Thus, for Aquinas, the truth of the human intellect (logical truth) is based on the truth in things (ontological truth). Following this, he wrote an elegant re-statement of Aristotle's view in his Summa I.16.1:
Veritas est adæquatio intellectus et rei.Aquinas also said that real things participate in the act of being of the Creator God who is Subsistent Being, Intelligence, and Truth. Thus, these beings possess the light of intelligibility and are knowable. These things (beings; reality) are the foundation of the truth that is found in the human mind, when it acquires knowledge of things, first through the senses, then through the understanding and the judgement done by reason. For Aquinas, human intelligence ("intus", within and "legere", to read) has the capability to reach the essence and existence of things because it has a non-material, spiritual element, although some moral, educational, and other elements might interfere with its capability.
(Truth is the conformity of the intellect to the things.)
Truth is said to consist in the agreement of knowledge with the object. According to this mere verbal definition, then, my knowledge, in order to be true, must agree with the object. Now, I can only compare the object with my knowledge by this means, namely, by taking knowledge of it. My knowledge, then, is to be verified by itself, which is far from being sufficient for truth. For as the object is external to me, and the knowledge is in me, I can only judge whether my knowledge of the object agrees with my knowledge of the object. Such a circle in explanation was called by the ancients Diallelos. And the logicians were accused of this fallacy by the sceptics, who remarked that this account of truth was as if a man before a judicial tribunal should make a statement, and appeal in support of it to a witness whom no one knows, but who defends his own credibility by saying that the man who had called him as a witness is an honourable man.According to Kant, the definition of truth as correspondence is a "mere verbal definition", here making use of Aristotle's distinction between a nominal definition: a definition in name only, and a real definition: a definition that shows the true cause or essence of the term that is being defined. From Kant's account of the history, the definition of truth as correspondence was already in dispute from classical times, the "skeptics" criticizing the "logicians" for a form of circular reasoning, though the extent to which the "logicians" actually held such a theory is not evaluated.
Hegel tried to distance his philosophy from psychology by presenting truth as being an external self–moving object instead of being related to inner, subjective thoughts. Hegel's truth is analogous to the mechanics of a material body in motion under the influence of its own inner force. "Truth is its own self–movement within itself." Teleological truth moves itself in the three–step form of dialectical triplicity toward the final goal of perfect, final, absolute truth. For Hegel, the progression of philosophical truth is a resolution of past oppositions into increasingly more accurate approximations to absolute truth. Chalybäus used the terms "thesis," "antithesis," and "synthesis" to describe Hegel's dialectical triplicity. The "thesis" consists of an incomplete historical movement. To resolve the incompletion, an "antithesis" occurs which opposes the "thesis." In turn, the "synthesis" appears when the "thesis" and "antithesis" become reconciled and a higher level of truth is obtained. This "synthesis" thereby becomes a "thesis," which will again necessitate an "antithesis," requiring a new "synthesis" until a final state is reached as the result of reason's historical movement. History is the Absolute Spirit moving toward a goal. This historical progression will finally conclude itself when the Absolute Spirit understands its own infinite self at the very end of history. Absolute Spirit will then be the complete expression of an infinite God.
For Schopenhauer, a judgment is a combination or separation of two or more concepts. If a judgment is to be an expression of knowledge, it must have a sufficient reason or ground by which the judgment could be called true. Truth is the reference of a judgment to something different from itself which is its sufficient reason (ground). Judgments can have material, formal, transcendental, or metalogical truth. A judgment has material truth if its concepts are based on intuitive perceptions that are generated from sensations. If a judgment has its reason (ground) in another judgment, its truth is called logical or formal. If a judgment, of, for example, pure mathematics or pure science, is based on the forms (space, time, causality) of intuitive, empirical knowledge, then the judgment has transcendental truth.
When Søren Kierkegaard, as his character Johannes Climacus, wrote that "Truth is Subjectivity", he does not advocate for subjectivism in its extreme form (the theory that something is true simply because one believes it to be so), but rather that the objective approach to matters of personal truth cannot shed any light upon that which is most essential to a person's life. Objective truths are concerned with the facts of a person's being, while subjective truths are concerned with a person's way of being. Kierkegaard agrees that objective truths for the study of subjects like mathematics, science, and history are relevant and necessary, but argues that objective truths do not shed any light on a person's inner relationship to existence. At best, these truths can only provide a severely narrowed perspective that has little to do with one's actual experience of life.
While objective truths are final and static, subjective truths are continuing and dynamic. The truth of one's existence is a living, inward, and subjective experience that is always in the process of becoming. The values, morals, and spiritual approaches a person adopts, while not denying the existence of objective truths of those beliefs, can only become truly known when they have been inwardly appropriated through subjective experience. Thus, Kierkegaard criticizes all systematic philosophies which attempt to know life or the truth of existence via theories and objective knowledge about reality. As Kierkegaard claims, human truth is something that is continually occurring, and a human being cannot find truth separate from the subjective experience of one's own existing, defined by the values and fundamental essence that consist of one's way of life.
Friedrich Nietzsche believed the search for truth or 'the will to truth' was a consequence of the will to power of philosophers. He thought that truth should be used as long as it promoted life and the will to power, and he thought untruth was better than truth if it had this life enhancement as a consequence. As he wrote in Beyond Good and Evil, "The falseness of a judgment is to us not necessarily an objection to a judgment... The question is to what extent it is life-advancing, life-preserving, species-preserving, perhaps even species-breeding..." (aphorism 4). He proposed the will to power as a truth only because according to him it was the most life affirming and sincere perspective one could have.
Robert Wicks discusses Nietzsche's basic view of truth as follows:
Some scholars regard Nietzsche's 1873 unpublished essay, "On Truth and Lies in a Nonmoral Sense" ("Über Wahrheit und Lüge im außermoralischen Sinn") as a keystone in his thought. In this essay, Nietzsche rejects the idea of universal constants, and claims that what we call "truth" is only "a mobile army of metaphors, metonyms, and anthropomorphisms." His view at this time is that arbitrariness completely prevails within human experience: concepts originate via the very artistic transference of nerve stimuli into images; "truth" is nothing more than the invention of fixed conventions for merely practical purposes, especially those of repose, security and consistence.
Alfred North Whitehead a British mathematician who became an American philosopher, said: "There are no whole truths; all truths are half-truths. It is trying to treat them as whole truths that play the devil".
The logical progression or connection of this line of thought is to conclude that truth can lie, since half-truths are deceptive and may lead to a false conclusion.
According to Kitaro Nishida, "knowledge of things in the world begins with the differentiation of unitary consciousness into knower and known and ends with self and things becoming one again. Such unification takes form not only in knowing but in the valuing (of truth) that directs knowing, the willing that directs action, and the feeling or emotive reach that directs sensing."
Erich Fromm finds that trying to discuss truth as "absolute truth" is sterile and that emphasis ought to be placed on "optimal truth". He considers truth as stemming from the survival imperative of grasping one's environment physically and intellectually, whereby young children instinctively seek truth so as to orient themselves in "a strange and powerful world". The accuracy of their perceived approximation of the truth will therefore have direct consequences on their ability to deal with their environment. Fromm can be understood to define truth as a functional approximation of reality. His vision of optimal truth is described partly in "Man from Himself: An Inquiry into the Psychology of Ethics" (1947), from which excerpts are included below.
- the dichotomy between 'absolute = perfect' and 'relative = imperfect' has been superseded in all fields of scientific thought, where "it is generally recognized that there is no absolute truth but nevertheless that there are objectively valid laws and principles".
- In that respect, "a scientifically or rationally valid statement means that the power of reason is applied to all the available data of observation without any of them being suppressed or falsified for the sake of a desired result". The history of science is "a history of inadequate and incomplete statements, and every new insight makes possible the recognition of the inadequacies of previous propositions and offers a springboard for creating a more adequate formulation."
- As a result "the history of thought is the history of an ever-increasing approximation to the truth. Scientific knowledge is not absolute but optimal; it contains the optimum of truth attainable in a given historical period." Fromm furthermore notes that "different cultures have emphasized various aspects of the truth" and that increasing interaction between cultures allows for these aspects to reconcile and integrate, increasing further the approximation to the truth.
Truth, for Michel Foucault, is problematic when any attempt is made to see truth as an "objective" quality. He prefers not to use the term truth itself but "Regimes of Truth". In his historical investigations he found truth to be something that was itself a part of, or embedded within, a given power structure. Thus Foucault's view shares much in common with the concepts of Nietzsche. Truth for Foucault is also something that shifts through various episteme throughout history.
Jean Baudrillard considered truth to be largely simulated, that is pretending to have something, as opposed to dissimulation, pretending to not have something. He took his cue from iconoclasts who he claims knew that images of God demonstrated the fact that God did not exist. Baudrillard wrote in "Precession of the Simulacra":
Some examples of simulacra that Baudrillard cited were: that prisons simulate the "truth" that society is free; scandals (eg, Watergate) simulate that corruption is corrected; Disney simulates that the U.S. itself is an adult place. One must remember that though such examples seem extreme, such extremity is an important part of Baudrillard's theory. For a less extreme example, consider how movies usually end with the bad being punished, humiliated, or otherwise failing, thus affirming for viewers the concept that the good end happily and the bad unhappily, a narrative which implies that the status quo and institutionalised power structures are largely legitimate.
Truth in logic
Theories of truth
- ↑ Merriam-Webster's Online Dictionary, truth, 2005
- ↑ see Holtzmann's law for the -ww- : -gg- alternation.
- ↑ A Concise Dictionary of Old Icelandic, Geir T. Zoëga (1910), Northvegr.org
- ↑ OED on true has "Steadfast in adherence to a commander or friend, to a principle or cause, to one's promises, faith, etc.; firm in allegiance; faithful, loyal, constant, trusty; Honest, honourable, upright, virtuous, trustworthy; free from deceit, sincere, truthful " besides "Conformity with fact; agreement with reality; accuracy, correctness, verity; Consistent with fact; agreeing with the reality; representing the thing as it is; Real, genuine; rightly answering to the description; properly so called; not counterfeit, spurious, or imaginary."
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 Encyclopedia of Philosophy, Supp., "Truth", auth: Michael Williams, p572-573 (Macmillan, 1996)
- ↑ Blackburn, Simon, and Simmons, Keith (eds., 1999), Truth, Oxford University Press, Oxford, UK. Includes papers by James, Ramsey, Russell, Tarski, and more recent work.
- ↑ Horwich, Paul, Truth, (2nd edition, 1988),
- ↑ Field, Hartry, Truth and the Absence of Fact (2001).
- ↑ Encyclopedia of Philosophy, Vol.2, "Correspondence Theory of Truth", auth: Arthur N. Prior, p223 (Macmillan, 1969) Prior uses Bertrand Russell's wording in defining correspondence theory. According to Prior, Russell was substantially responsible for helping to make correspondence theory widely known under this name.
- ↑ Encyclopedia of Philosophy, Vol.2, "Correspondence Theory of Truth", auth: Arthur N. Prior, p223-224 Macmillan, 1969)
- ↑ Encyclopedia of Philosophy, Vol.2, "Correspondence Theory of Truth", auth: Arthur N. Prior, p224, Macmillan, 1969.
- ↑ "Correspondence Theory of Truth", in Stanford Encyclopedia of Philosophy.
- ↑ "Correspondence Theory of Truth", in Stanford Encyclopedia of Philosophy, (citing De Veritate Q.1, A.1&3; cf. Summa Theologiae Q.16).
- ↑ See, e.g., Bradley, F.H., "On Truth and Copying", in Blackburn, et al. (eds., 1999),Truth, 31-45.
- ↑ Encyclopedia of Philosophy, Vol.2, "Correspondence Theory of Truth", auth: Arthur N. Prior, p223 ff. Macmillan, 1969). See especially, section on "Moore's Correspondence Theory", 225-226, "Russell's Correspondence Theory", 226-227, "Remsey and Later Wittgenstein", 228-229, "Tarski's Semantic Theory", 230-231.
- ↑ Encyclopedia of Philosophy, Vol.2, "Correspondence Theory of Truth", auth: Arthur N. Prior, p223 ff. Macmillan, 1969). See the section on "Tarski's Semantic Theory", 230-231.
- ↑ Immanuel Kant, for instance, assembled a controversial but quite coherent system in the early 19th century, whose validity and usefulness continues to be debated even today. Similarly, the systems of Leibniz and Spinoza are characteristic systems that are internally coherent but controversial in terms of their utility and validity.
- ↑ Encyclopedia of Philosophy, Vol.2, "Coherence Theory of Truth", auth: Alan R. White, p130-131 (Macmillan, 1969)
- ↑ Encyclopedia of Philosophy, Vol.2, "Coherence Theory of Truth", auth: Alan R. White, p131-133, see esp., section on "Epistemological assumptions" (Macmillan, 1969)
- ↑ Encyclopedia of Philosophy, Vol.2, "Coherence Theory of Truth", auth: Alan R. White, p130
- ↑ May, Todd, 1993, Between Genealogy and Epistemology: Psychology, politics in the thought of Michel Foucault' with reference to Althusser and Balibar, 1970
- ↑ See, e.g., Habermas, Jürgen, Knowledge and Human Interests (English translation, 1972).
- ↑ See, e.g., Habermas, Jürgen, Knowledge and Human Interests (English translation, 1972), esp. PART III, pp 187 ff.
- ↑ Rescher, Nicholas, Pluralism: Against the Demand for Consensus (1995).
- ↑ Encyclopedia of Philosophy, Vol.5, "Pragmatic Theory of Truth", 427 (Macmillan, 1969).
- ↑ 26.0 26.1 Peirce, C.S. (1901), "Truth and Falsity and Error" (in part), pp. 716–720 in James Mark Baldwin, ed., Dictionary of Philosophy and Psychology, v. 2. Peirce's section is entitled "Logical", beginning on p. 718, column 1, and ending on p. 720 with the intials "(C.S.P.)", see Google Books Eprint. Reprinted, Collected Papers v. 5, pp. 565–573.
- ↑ 27.0 27.1 James, William, The Meaning of Truth, A Sequel to 'Pragmatism', (1909).
- ↑ Encyclopedia of Philosophy, Vol.2, "Dewey, John", auth Richard J. Bernstein, p383 (Macmillan, 1969)
- ↑ Blackburn, Simon, and Simmons, Keith (eds., 1999), Truth in the Introductory section of the book.
- ↑ Kirkham, Theories of Truth, MIT Press, 1992.
- ↑ J. L. Austin, "How to Do Things With Words". Cambridge: Harvard University Press, 1975
- ↑ Encyclopedia of Philosophy, Vol.6: Performative Theory of Truth, auth: Gertrude Ezorsky, p88 (Macmillan, 1969)
- ↑ Ramsey, F.P. (1927), "Facts and Propositions", Aristotelian Society Supplementary Volume 7, 153–170. Reprinted, pp. 34–51 in F.P. Ramsey, Philosophical Papers, David Hugh Mellor (ed.), Cambridge University Press, Cambridge, UK, 1990
- ↑ Le Morvan, Pierre. (2004) "Ramsey on Truth and Truth on Ramsey", The British Journal for the History of Philosophy 12(4), pp. 705-718.
- ↑ Truth and Objectivity, Cambridge, MA: Harvard University Press, 1992.
- ↑ Truth as One and Many (Oxford: Oxford University Press, 2009).
- ↑ http://philpapers.org/surveys/results.pl?affil=All+respondents&areas0=0&areas_max=1&grain=medium
- ↑ Ludwig Wittgenstein, Tractatus Logico-Philosophicus
- ↑ See, e.g., Chaitin, Gregory L., The Limits of Mathematics (1997) esp. 89 ff.
- ↑ M. Davis. "Hilbert's Tenth Problem is Unsolvable." American Mathematical Monthly 80, pp. 233-269, 1973
- ↑ Yandell, Benjamin H.. The Honors Class. Hilbert's Problems and Their Solvers (2002).
- ↑ Chaitin, Gregory L., The Limits of Mathematics (1997) 1-28, 89 ff.
- ↑ Kripke, Saul. "Outline of a Theory of Truth", Journal of Philosophy, 72 (1975), 690-716
- ↑ See, for example, Father John Corapi's Easter Triduum.
- ↑ John 14:6.
- ↑ Catechism of the Catholic Church #2464.
- ↑ Catechism of the Catholic Church #2466.
- ↑ Catechism of the Catholic Church #2466.
- ↑ .
- ↑ 50.0 50.1 50.2 50.3 David, Marion (2005). "Correspondence Theory of Truth" in Stanford Encyclopedia of Philosophy
- ↑ Osman Amin (2007), "Influence of Muslim Philosophy on the West", Monthly Renaissance 17 (11).
- ↑ Jan A. Aertsen (1988), Nature and Creature: Thomas Aquinas's Way of Thought, p. 152. BRILL, ISBN 9004084517.
- ↑ Simone van Riet. Liber de philosophia prima, sive Scientia divina (in Latin).
- ↑ (2005) Avicenna: The Metaphysics of The Healing, Brigham Young University Press.
- ↑ Disputed Questions on Truth, 1, 2, c, reply to Obj. 1. Trans. Mulligan, McGlynn, Schmidt, Truth, vol. I, pp. 10-12.
- ↑ "Veritas supra ens fundatur" (Truth is founded on being). Disputed Questions on Truth, 10, 2, reply to Obj. 3.
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- ↑ "Die Wahrheit ist die Bewegung ihrer an ihr selbst." The Phenomenology of Spirit, Preface, ¶ 48
- ↑ On the Fourfold Root of the Principle of Sufficient Reason, §§ 29–33
- ↑ Kierkegaard, Søren. Concluding Unscientific Postscript. Princeton, Princeton University Press, 1992
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- ↑ Baudrillard's attribution of this quote to Ecclesiastes is deliberately fictional. "Baudrillard attributes this quote to Ecclesiastes. However, the quote is a fabrication (see Jean Baudrillard. Cool Memories III, 1991-95. London: Verso, 1997). Editor’s note: In Fragments: Conversations With François L’Yvonnet. New York: Routledge, 2004:11, Baudrillard acknowledges this 'Borges-like' fabrication." Cited in footnote #4 in Smith, Richard G., "Lights, Camera, Action: Baudrillard and the Performance of Representations", International Journal of Baudrillard Studies, Volume 2, Number 1 (January 2005)
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Theories of Truth
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