Truth in the context of Münchhausen trilemma

History is the systematic study of the past, focusing primarily on the human past. As an academic discipline, it analyses and interprets evidence to construct narratives about what happened and explain why it happened. Some theorists categorize history as a social science, while others see it as part of the humanities or consider it a hybrid discipline. Similar debates surround the purpose of history—for example, whether its main aim is theoretical, to uncover the truth, or practical, to learn lessons from the past. In a more general sense, the term history refers not to an academic field but to the past itself, times in the past, or to individual texts about the past.

Historical research relies on primary and secondary sources to reconstruct past events and validate interpretations. Source criticism is used to evaluate these sources, assessing their authenticity, content, and reliability. Historians strive to integrate the perspectives of several sources to develop a coherent narrative. Different schools of thought, such as positivism, the Annales school, Marxism, and postmodernism, have distinct methodological approaches.

Reason is the capacity of consciously applying logic by drawing valid conclusions from new or existing information, with the aim of seeking truth. It is associated with such characteristically human activities as philosophy, religion, science, language, and mathematics, and is normally considered to be a distinguishing ability possessed by humans. Reason is sometimes referred to as rationality, although the latter is more about its application.

Reasoning involves using more-or-less rational processes of thinking and cognition to extrapolate from one's existing knowledge to generate new knowledge, and involves the use of one's intellect. The field of logic studies the ways in which humans can use formal reasoning to produce logically valid arguments and true conclusions. Reasoning may be subdivided into forms of logical reasoning, such as deductive reasoning, inductive reasoning, and abductive reasoning.

Epistemology is the branch of philosophy that examines the nature, origin, and limits of knowledge. Also called the theory of knowledge, it explores different types of knowledge, such as propositional knowledge about facts, practical knowledge in the form of skills, and knowledge by acquaintance as a familiarity through experience. Epistemologists study the concepts of belief, truth, and justification to understand the nature of knowledge. To discover how knowledge arises, they investigate sources of justification, such as perception, introspection, memory, reason, and testimony.

The school of skepticism questions the human ability to attain knowledge, while fallibilism says that knowledge is never certain. Empiricists hold that all knowledge comes from sense experience, whereas rationalists believe that some knowledge does not depend on it. Coherentists argue that a belief is justified if it coheres with other beliefs. Foundationalists, by contrast, maintain that the justification of basic beliefs does not depend on other beliefs. Internalism and externalism debate whether justification is determined solely by mental states or also by external circumstances.

A belief is a subjective attitude that something is true or a state of affairs is the case. A subjective attitude is a mental state of having some stance, take, or opinion about something. In epistemology, philosophers use the term belief to refer to attitudes about the world which can be either true or false. To believe something is to take it to be true; for instance, to believe that snow is white is comparable to accepting the truth of the proposition "snow is white". However, holding a belief does not require active introspection. For example, few individuals carefully consider whether or not the sun will rise the next morning, simply assuming that it will. Moreover, beliefs need not be occurrent (e.g., a person actively thinking "snow is white"), but can instead be dispositional (e.g., a person who if asked about the color of snow would assert "snow is white").

There are various ways that contemporary philosophers have tried to describe beliefs, including as representations of ways that the world could be (Jerry Fodor), as dispositions to act as if certain things are true (Roderick Chisholm), as interpretive schemes for making sense of someone's actions (Daniel Dennett and Donald Davidson), or as mental states that fill a particular function (Hilary Putnam). Some have also attempted to offer significant revisions to our notion of belief, including eliminativists about belief who argue that there is no phenomenon in the natural world which corresponds to our folk psychological concept of belief (Paul Churchland) and formal epistemologists who aim to replace our bivalent notion of belief ("either we have a belief or we don't have a belief") with the more permissive, probabilistic notion of credence ("there is an entire spectrum of degrees of belief, not a simple dichotomy between belief and non-belief").

Evidence for a proposition is what supports the proposition. It is usually understood as an indication that the proposition is true. The exact definition and role of evidence vary across different fields.

In epistemology, evidence is what justifies beliefs or what makes it rational to hold a certain doxastic attitude. For example, a perceptual experience of a tree may serve as evidence to justify the belief that there is a tree. In this role, evidence is usually understood as a private mental state. In phenomenology, evidence is limited to intuitive knowledge, often associated with the controversial assumption that it provides indubitable access to truth.

Knowledge is an awareness of facts, a familiarity with individuals and situations, or a practical skill. Knowledge of facts, also called propositional knowledge, is often characterized as true belief that is distinct from opinion or guesswork by virtue of justification. While there is wide agreement among philosophers that propositional knowledge is a form of true belief, many controversies focus on justification. This includes questions like how to understand justification, whether it is needed at all, and whether something else besides it is needed. These controversies intensified in the latter half of the 20th century due to a series of thought experiments called Gettier cases that provoked alternative definitions.

Knowledge can be produced in many ways. The main source of empirical knowledge is perception, which involves the usage of the senses to learn about the external world. Introspection allows people to learn about their internal mental states and processes. Other sources of knowledge include memory, rational intuition, inference, and testimony. According to foundationalism, some of these sources are basic in that they can justify beliefs, without depending on other mental states. Coherentists reject this claim and contend that a sufficient degree of coherence among all the mental states of the believer is necessary for knowledge. According to infinitism, an infinite chain of beliefs is needed.

Friedrich Wilhelm Nietzsche (15 October 1844 – 25 August 1900) was a German philosopher. He began his career as a classical philologist, turning to philosophy early in his academic career. In 1869, aged 24, Nietzsche became the youngest professor to hold the Chair of Classical Philology at the University of Basel. Plagued by health problems for most of his life, he resigned from the university in 1879, and in the following decade he completed much of his core writing. In 1889, aged 44, he suffered a collapse and thereafter a complete loss of his mental faculties, with paralysis and vascular dementia, living his remaining 11 years under the care of his family until his death. His works and his philosophy have fostered not only extensive scholarship but also much popular interest.

Nietzsche's work encompasses philosophical polemics, poetry, cultural criticism and fiction, while displaying a fondness for aphorisms and irony. Prominent elements of his philosophy include his radical critique of truth in favour of perspectivism; a genealogical critique of religion and Christian morality and a related theory of master–slave morality; the aesthetic affirmation of life in response to both the "death of God" and the profound crisis of nihilism; the notion of Apollonian and Dionysian forces; and a characterisation of the human subject as the expression of competing wills, collectively understood as the will to power. He also developed influential concepts such as the Übermensch and his doctrine of eternal return. In his later work he became increasingly preoccupied with the creative powers of the individual to overcome cultural and moral mores in pursuit of new values and aesthetic health. His body of work touched a wide range of topics, including art, philology, history, music, religion, tragedy, culture and science, and drew inspiration from Hebrew literature, Indian literature and Greek tragedy, as well as figures such as Zoroaster, Arthur Schopenhauer, Ralph Waldo Emerson, Richard Wagner, Fyodor Dostoevsky and Johann Wolfgang von Goethe.

Dialectic (Ancient Greek: διαλεκτική, romanized: dialektikḗ; German: Dialektik), also known as the dialectical method, refers originally to dialogue between people holding different points of view about a subject but wishing to arrive at the truth through reasoned argument. Dialectic resembles debate, but the concept excludes subjective elements such as emotional appeal and rhetoric; the object is more an eventual and commonly-held truth than the 'winning' of an (often binary) competition. It has its origins in ancient philosophy and continued to be developed in the Middle Ages.

Hegelianism refigured "dialectic" to no longer refer to a literal dialogue. Instead, the term takes on the specialized meaning of development by way of overcoming internal contradictions. Dialectical materialism, a theory advanced by Karl Marx and Friedrich Engels, adapted the Hegelian dialectic into a materialist theory of history. The legacy of Hegelian and Marxian dialectics has been criticized by philosophers, such as Karl Popper and Mario Bunge, who considered it unscientific.

A fact is a true datum about one or more aspects of a circumstance. Standard reference works are often used to check facts. Scientific facts are verified by repeatable careful observation or measurement by experiments or other means. Generally speaking, facts are independent of belief, knowledge and opinion. Facts are different from inferences, theories, values, and objects.

For example, "This sentence contains words." accurately describes a linguistic fact, and "the Sun is a star" describes an astronomical fact. Further, "Abraham Lincoln was the 16th president of the United States" and "Abraham Lincoln was assassinated" are both historical facts.

Mimesis (/mɪˈmiːsɪs, maɪ-/; Ancient Greek: μίμησις, mīmēsis) is a term used in literary criticism and philosophy that carries a wide range of meanings, including imitatio, imitation, similarity, receptivity, representation, mimicry, the act of expression, the act of resembling, and the presentation of the self.

The original Ancient Greek term mīmēsis (μίμησις) derives from mīmeisthai (μιμεῖσθαι, 'to imitate'), itself coming from mimos (μῖμος, 'imitator, actor'). In ancient Greece, mīmēsis was an idea that governed the creation of works of art, in particular, with correspondence to the physical world understood as a model for beauty, truth, and the good. Plato contrasted mimesis, or imitation, with diegesis, or narrative. After Plato, the meaning of mimesis eventually shifted toward a specifically literary function in ancient Greek society.

Intellect is a faculty of the human mind that enables reasoning, abstraction, conceptualization, and judgment. It enables the discernment of truth and falsehood, as well as higher-order thinking beyond immediate perception. Intellect is distinct from intelligence, which refers to the general ability to learn, adapt, and solve problems, whereas intellect concerns the application of reason to abstract or philosophical thought.

In philosophy, intellect (Ancient Greek: dianoia) has often been contrasted with nous, a term referring to the faculty of direct intuitive knowledge. While intellect engages in discursive reasoning, breaking down concepts into logical sequences, nous is considered a higher cognitive faculty that allows for direct perception of truth, especially in Platonism and Neoplatonism. Aristotle distinguished between the active intellect (intellectus agens), which abstracts universal concepts, and the passive intellect, which receives sensory input.

In logic, specifically in deductive reasoning, an argument is valid if and only if it takes a form that makes it impossible for the premises to be true and the conclusion nevertheless to be false. It is not required for a valid argument to have premises that are actually true, but to have premises that, if they were true, would guarantee the truth of the argument's conclusion. Valid arguments must be clearly expressed by means of sentences called well-formed formulas (also called wffs or simply formulas).

The validity of an argument can be tested, proved or disproved, and depends on its logical form.

Declarative knowledge is an awareness of facts that can be expressed using declarative sentences. It is also called theoretical knowledge, descriptive knowledge, propositional knowledge, and knowledge-that. It is not restricted to one specific use or purpose and can be stored in books or on computers.

Epistemology is the main discipline studying declarative knowledge. Among other things, it studies the essential components of declarative knowledge. According to a traditionally influential view, it has three elements: it is a belief that is true and justified. As a belief, it is a subjective commitment to the accuracy of the believed claim while truth is an objective aspect. To be justified, a belief has to be rational by being based on good reasons. This means that mere guesses do not amount to knowledge even if they are true. In contemporary epistemology, additional or alternative components have been suggested. One proposal is that no contradicting evidence is present. Other suggestions are that the belief was caused by a reliable cognitive process and that the belief is infallible.

In philosophy, rationalism is the epistemological view that "regards reason as the chief source and test of knowledge" or "the position that reason has precedence over other ways of acquiring knowledge", often in contrast to other possible sources of knowledge such as faith, tradition, or sensory experience. More formally, rationalism is defined as a methodology or a theory "in which the criterion of truth is not sensory but intellectual and deductive".

In a major philosophical debate during the Enlightenment, rationalism (sometimes here equated with innatism) was opposed to empiricism. On the one hand, rationalists like René Descartes emphasized that knowledge is primarily innate and the intellect, the inner faculty of the human mind, can therefore directly grasp or derive logical truths; on the other hand, empiricists like John Locke emphasized that knowledge is not primarily innate and is best gained by careful observation of the physical world outside the mind, namely through sensory experiences. Rationalists asserted that certain principles exist in logic, mathematics, ethics, and metaphysics that are so fundamentally true that denying them causes one to fall into contradiction. The rationalists had such a high confidence in reason that empirical proof and physical evidence were regarded as unnecessary to ascertain certain truths – in other words, "there are significant ways in which our concepts and knowledge are gained independently of sense experience".

In philosophical epistemology, there are two types of coherentism: the coherence theory of truth, and the coherence theory of justification (also known as epistemic coherentism).

Coherent truth is divided between an anthropological approach, which applies only to localized networks ('true within a given sample of a population, given our understanding of the population'), and an approach that is judged on the basis of universals, such as categorical sets. The anthropological approach belongs more properly to the correspondence theory of truth, while the universal theories are a small development within analytic philosophy.

An axiom, postulate, or assumption is a statement that is taken to be true, to serve as a premise or starting point for further reasoning and arguments. The word comes from the Ancient Greek word ἀξίωμα (axíōma), meaning 'that which is thought worthy or fit' or 'that which commends itself as evident'.

The precise definition varies across fields of study. In classic philosophy, an axiom is a statement that is so evident or well-established, that it is accepted without controversy or question. In modern logic, an axiom is a premise or starting point for reasoning.

Logical truth is one of the most fundamental concepts in logic. Broadly speaking, a logical truth is a statement which is true regardless of the truth or falsity of its constituent propositions. In other words, a logical truth is a statement which is not only true, but one which is true under all interpretations of its logical components (other than its logical constants). Thus, logical truths such as "if p, then p" can be considered tautologies. Logical truths are thought to be the simplest case of statements which are analytically true (or in other words, true by definition). All of philosophical logic can be thought of as providing accounts of the nature of logical truth, as well as logical consequence.

Logical truths are generally considered to be necessarily true. This is to say that they are such that no situation could arise in which they could fail to be true. The view that logical statements are necessarily true is sometimes treated as equivalent to saying that logical truths are true in all possible worlds. However, the question of which statements are necessarily true remains the subject of continued debate.

A premise or premiss is a proposition—a true or false declarative statement—used in an argument to prove the truth of another proposition called the conclusion. Arguments consist of a set of premises and a conclusion.

An argument is meaningful for its conclusion only when all of its premises are true. If one or more premises are false, the argument says nothing about whether the conclusion is true or false. For instance, a false premise on its own does not justify rejecting an argument's conclusion; to assume otherwise is a logical fallacy called denying the antecedent. One way to prove that a proposition is false is to formulate a sound argument with a conclusion that negates that proposition.