Truth

• 1. Introduction

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  Truth is conformity to reality or fact. A sentence like "the carrot is orange" seems to demand nothing more than a glance at the carrot. Yet philosophers have argued about what makes such a sentence true for thousands of years, and they still disagree. The statement "I am lying" tangles itself into knots. If it is true, it must be false. If it is false, it must be true. That single sentence, known as the liar paradox, has resisted easy answers since antiquity. How can something so ordinary, so woven into law, science, religion, and everyday honesty, lack an agreed definition? What does it mean for words to match the world, and who decides when they do? The questions begin with a carrot and reach all the way to God.

• 2. What Carries Truth

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  Sentences like "It's raining in Nairobi" are concrete strings of words, public and clearly structured. That public nature aids analysis, but it brings trouble. A sentence may be true under one interpretation and false under another, because meaning shifts with context and ambiguous terms. Sentences also belong to specific languages, which risks limiting philosophy to features of one tongue rather than universal principles.

  Propositions offer an escape from these snags. Treated as abstract entities that serve as the meanings of declarative sentences, they sidestep context dependence, ambiguity, and language specificity. Their abstractness comes at a price, since some philosophers doubt that abstract objects exist at all. Beliefs form a third candidate, concrete psychological states that link truth directly to cognition, yet remain hard to study because they are private.

  Monists insist on a single kind of truthbearer, while pluralists accept several. Some thinkers name one kind as primary and explain the rest through it. One proposal reduces the truth of beliefs to sentences, on the grounds that sentences can be used to express beliefs.

• 3. Anchored In Reality

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  An orange carrot can act as a truthmaker for the sentence "the carrot is orange." A truthmaker is a real entity whose existence makes a truthbearer true, linking thought and language to the world. Candidates include facts or states of affairs, tropes, and particular objects. Truthmakers are often treated as sufficient conditions, meaning their existence alone is enough to make a sentence true.

  Truth conditions describe the circumstances under which a statement holds. One truth condition of "it is raining" is that raindrops are falling. These are usually treated as necessary conditions, so if the condition fails to obtain, the sentence cannot be true. The motivation behind both ideas is that truth depends on reality rather than floating free as a mere convention. The carrot, not the speaker, settles the matter.

• 4. Honesty And Its Shadows

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  Someone may state a truth with the intent to deceive, and a liar may accidentally tell a truth. Truthfulness is a virtue tied to honesty and consistency among one's words, beliefs, and behavior, and truth alone is not enough to secure it. A person who sincerely states a false belief may still be truthful. Lying occurs when a speaker intentionally says something they believe to be false.

  Bullshitting describes a speaker indifferent to truth or falsehood, caring only about persuading or manipulating the audience. Truthiness names the tendency to prioritize intuition and gut feelings over evidence and rational analysis, overlapping with the term post-truth, where public opinion is shaped by appeals to emotion rather than objective facts. Deception can also take non-verbal forms, including edited photographs and deepfakes designed to mislead.

  Verisimilitude, also called truthlikeness, applies to theories that approximate the truth without reaching it. Heliocentrism is correct that planets orbit the sun but wrong that the orbits are perfect circles, so it is not strictly true, only truthlike. It is more truthlike than geocentrism, which places the Earth at the center of the universe. Some suggest truth itself comes in degrees, an idea found in fuzzy logics, against the traditional bivalent view that an assertion is either true or false.

• 5. Competing Theories

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  The correspondence theory, one of the oldest and most influential, holds that a belief or statement is true if it corresponds to facts. Critics charge it with being uninformative or circular, since it never explains what correspondence means. Others object that it is too narrow, struggling to account for truth in mathematics, logic, and morality, where independent facts are hard to identify. Truthmaker theory is often treated as a modern version of it, with truthmaker maximalism asserting that every truth has a truthmaker.

  The coherence theory understands truth as a relation between beliefs rather than between a belief and a fact. A belief is true if it belongs to a coherent web of beliefs. The belief that photons lack mass rests on a network of ideas from particle physics. Critics reply that a fictional story does not become true just because it is coherent, and that competing coherent sets may contradict each other.

  Pragmatists characterize truth by the role it plays in human affairs. One version says truth is what works, what has beneficial consequences when acted upon. A difficulty is that a false belief may sometimes have good consequences. A different version defines truth as the ideal limit of inquiry, or what researchers would believe after unlimited investigation.

  The semantic theory, originally formulated by Alfred Tarski, analyzes truth through T-sentences. The example "'La nieve es blanca.' is true in Spanish if and only if snow is white" treats Spanish as the object language and English as the meta-language. Tarski limited his view to formal languages, while Donald Davidson later applied it to natural languages. Talking about truth through a meta-language helps avoid paradoxes like the liar paradox.

  Deflationary theories argue that truth has no significant intrinsic nature. The redundancy theory claims that "Snow is white" and "'Snow is white' is true" have the same meaning, with the predicate adding nothing. Disquotationalism treats "is true" as a device for removing quotation marks, while the performative theory treats it as a way to endorse statements, as when saying "That's true."

• 6. Many Kinds Of True

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  Water boils at 100 degrees Celsius at standard atmospheric pressure, a fact known only through sensory experience, marking it as a posteriori truth. A priori truths can be known through pure reasoning, such as a proof of a mathematical theorem. Synthetic truths depend on what the world is like, as with "Mount Everest is the highest mountain on Earth." Analytic truths depend only on the meanings of their terms, as in "all bachelors are unmarried."

  Logical truths form a special class whose truth is fixed by logical form alone. Their negation is a contradiction, such as "the light is on and the light is not on." Most logicians treat all contradictions as false to avoid absurdity. The school of dialetheism is the exception, holding that some contradictions are true and that reality itself can be contradictory.

  Evaluative truths concern what is good or bad. Ethical truths assess the moral status of actions, as in "murder is wrong," while aesthetic truths concern beauty and the meanings of artworks. Axiological nihilists and error theorists deny that such truths exist. The claim "Harry Potter wears glasses" illustrates truth in fiction, a statement that accurately describes the imagined universe of a work. In model theory, a formula may be true in one model and false in another, and a sentence true in the actual world can be false in some possible world where the dinosaurs survived.

• 7. Faith And The Divine

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  Jesus's statement "I am the way, the truth, and the life" places truth at the heart of Christianity. The Abrahamic traditions closely link truth to the divine, reflected in the Jewish description of God as El Emet, meaning God of Truth, and in the Islamic term Al-Haqq as one of Allah's names. Philosophers in these traditions debated whether the truths of faith and the truths of reason conflict, often arguing that apparent tensions dissolve through right interpretation, or invoking the doctrine of double truth.

  In Hinduism, truth or satya is a virtue practiced in thought, speech, and action, and counts as one of the five moral restraints in Patanjali's Yoga. Buddhism formulated the Four Noble Truths about the causes of suffering and the path to liberation, along with the theory of two truths, separating conventional truth of everyday experience from ultimate truth about the fundamental nature of reality. Jainism draws a related contrast between relative truth, bound to time, place, and perspective, and absolute truth, which transcends viewpoints but cannot be fully expressed in language. Taoism holds a form of perspectivism, treating each viewpoint as a partial view of reality.

• 8. From Antiquity To The Present

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  The Rigveda, composed in the 2nd millennium BCE, stressed the spiritual importance of truthfulness and explored the relation between cosmic truth and individual truth. Jainism flourished in the 6th century BCE, around the same era that Buddhism originated. In ancient Greek thought, truth was understood as aletheia or disclosure. Parmenides distinguished truth from opinion, Protagoras proposed that "man is the measure of all things," and Aristotle (384 to 322 BCE) conceived an early form of the correspondence theory, holding that something can be true even if no one thinks about it.

  Augustine of Hippo (354 to 430 CE) maintained that truth is identical to God. Anselm of Canterbury (1033 to 1109 CE) argued that truth primarily resides in things that participate in God as the highest truth. Thomas Aquinas (1225 to 1274 CE) held that a thing is true if it matches God's idea of it. In Islamic thought, Avicenna (c. 980 to 1037 CE) distinguished three senses of truth, including the reality of individual entities and the divine reality of God as a necessary being.

  René Descartes (1596 to 1650) argued for clear and distinct ideas that cannot be doubted. Immanuel Kant treated judgments as the main truthbearers and held that people have a duty to tell the truth, prohibited from lying. Søren Kierkegaard (1813 to 1855) emphasized subjective truth in the slogan "truth is subjectivity." Friedrich Nietzsche (1844 to 1900) saw truth as an expression of the will to power and favored perspectivism over correspondence. William James characterized truth through practical consequences, while C. S. Peirce held that truth is what would result after endless inquiry.

  Among twentieth-century figures, G. E. Moore and Bertrand Russell first defended truth as an indefinable property, then proposed a fact-based correspondence theory. Ludwig Wittgenstein (1889 to 1951) defined truth as correspondence in which a proposition pictures a fact. Martin Heidegger understood truth as unconcealment, recovering the Greek aletheia. Michel Foucault explored how institutions determine what counts as truth and use it to wield power, a reminder that the carrot still waits on the table while the argument continues.