philosophy Philosophy ('love of wisdom' in Ancient Greek) is a systematic study of general and fundamental questions concerning topics like existence, reason, knowledge, Value (ethics and social sciences), value, mind, and language. It is a rational an ...

, verisimilitude (or truthlikeness) is the notion that some

proposition A proposition is a statement that can be either true or false. It is a central concept in the philosophy of language, semantics, logic, and related fields. Propositions are the object s denoted by declarative sentences; for example, "The sky ...

s are closer to being true than other propositions. The problem of verisimilitude is the problem of articulating what it takes for one false

theory A theory is a systematic and rational form of abstract thinking about a phenomenon, or the conclusions derived from such thinking. It involves contemplative and logical reasoning, often supported by processes such as observation, experimentation, ...

to be closer to the truth than another false theory. This problem was central to the

Karl Popper Sir Karl Raimund Popper (28 July 1902 – 17 September 1994) was an Austrian–British philosopher, academic and social commentator. One of the 20th century's most influential philosophers of science, Popper is known for his rejection of the ...

, largely because Popper was among the first to affirm that truth is the aim of scientific inquiry while acknowledging that most of the greatest scientific theories in the

history of science The history of science covers the development of science from ancient history, ancient times to the present. It encompasses all three major branches of science: natural science, natural, social science, social, and formal science, formal. Pr ...

are, strictly speaking, false. If this long string of purportedly false theories is to constitute progress with respect to the goal of truth, then it must be at least possible for one false theory to be closer to the truth than others.

Karl Popper

Popper's formal definition of verisimilitude was challenged since 1974 by Pavel Tichý, John Henry Harris, and David Miller, who argued that Popper's definition has an unintended consequence: that no false theory can be closer to the truth than another. Popper himself stated: "I accepted the criticism of my definition within minutes of its presentation, wondering why I had not seen the mistake before." This result gave rise to a search for an account of verisimilitude that did not deem progress towards the truth an impossibility.

Post-Popperian theories

Theories proposed by David Miller and by Theo Kuipers build on Popper's approach, guided by the notion that truthlikeness is a function of a truth factor and a content factor. Others (e.g. those advanced by in collaboration with , by Mortensen, and by Ken Gemes) are also inspired by Popper's approach but locate what they believe to be the error of Popper's proposal in his overly generous notion of content, or consequence, proposing instead that the consequences that contribute to closeness to truth must be, in a technical sense, "relevant". A different approach (already proposed by Tichý and and developed especially by Ilkka Niiniluoto and Graham Oddie) takes the "likeness" in truthlikeness literally, holding that a proposition's likeness to the truth is a function of the overall likeness to the actual world of the possible worlds in which the proposition would be true. An attempt to use the notion of point-free metric space is proposed by Giangiacomo Gerla. There is currently a debate about whether or to what extent these different approaches to the concept are compatible.

References

{{Karl Popper Concepts in epistemology Concepts in the philosophy of science Epistemology of science Karl Popper

Karl Popper

Post-Popperian theories

See also

References