Type–token distinction in the context of "Abstract thinking"

Abstraction is the process of generalizing rules and concepts from specific examples, literal (real or concrete) signifiers, first principles, or other methods. The result of the process, an abstraction, is a concept that acts as a common noun for all subordinate concepts and connects any related concepts as a group, field, or category.

Abstractions and levels of abstraction play an important role in the theory of general semantics originated by Alfred Korzybski. Anatol Rapoport wrote "Abstracting is a mechanism by which an infinite variety of experiences can be mapped on short noises (words)." An abstraction can be constructed by filtering the information content of a concept or an observable phenomenon, selecting only those aspects that are relevant for a particular purpose. For example, abstracting a leather soccer ball to the more general idea of a ball selects only the information on general ball attributes and behavior, excluding but not eliminating the other phenomenal and cognitive characteristics of that particular ball. In a type–token distinction, a type (e.g., a 'ball') is more abstract than its tokens (e.g., 'that leather soccer ball').

A truth-bearer is an entity that is said to be either true or false and nothing else. The thesis that some things are true while others are false has led to different theories about the nature of these entities. Since there is divergence of opinion on the matter, the term truth-bearer is used to be neutral among the various theories. Truth-bearer candidates include propositions, sentences, sentence-tokens, statements, beliefs, thoughts, intuitions, utterances, and judgements but different authors exclude one or more of these, deny their existence, argue that they are true only in a derivative sense, assert or assume that the terms are synonymous,or seek to avoid addressing their distinction or do not clarify it.

Type physicalism (also known as reductive materialism, type identity theory, mind–brain identity theory, and identity theory of mind) is a physicalist theory in the philosophy of mind. It asserts that mental events can be grouped into types, and can then be correlated with types of physical events in the brain. For example, one type of mental event, such as "mental pains" will, presumably, turn out to be describing one type of physical event (like C-fiber firings).

Type physicalism is contrasted with token identity physicalism, which argues that mental events are unlikely to have "steady" or categorical biological correlates. These positions make use of the philosophical type–token distinction (e.g., Two persons having the same "type" of car need not mean that they share a "token", a single vehicle). Type physicalism can now be understood to argue that there is an identity between types (any mental type is identical with some physical type), whereas token identity physicalism says that every token mental state/event/property is identical to some brain state/event/property.

The abundance of the chemical elements is a measure of the occurrences of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by mass fraction (in commercial contexts often called weight fraction), by mole fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases), or by volume fraction. Volume fraction is a common abundance measure in mixed gases such as planetary atmospheres, and is similar in value to molecular mole fraction for gas mixtures at relatively low densities and pressures, and ideal gas mixtures. Most abundance values in this article are given as mass fractions.

The abundance of chemical elements in the universe is dominated by the large amounts of hydrogen and helium which were produced during Big Bang nucleosynthesis. Remaining elements, making up only about 2% of the universe, were largely produced by supernova nucleosynthesis. Elements with even atomic numbers are generally more common than their neighbors in the periodic table, due to their favorable energetics of formation, described by the Oddo–Harkins rule.

A logical symbol is a fundamental concept in logic, tokens of which may be marks or a configuration of marks which form a particular pattern. Although the term symbol in common use sometimes refers to the idea being symbolized, and at other times to the marks on a piece of paper or chalkboard which are being used to express that idea; in the formal languages studied in mathematics and logic, the term symbol refers to the idea, and the marks are considered to be a token instance of the symbol. In logic, symbols build literal utility to illustrate ideas.

In knowledge representation, a class is a collection of individuals or individuals objects. A class can be defined either by extension (specifying members), or by intension (specifying conditions). According to the type–token distinction, the ontology is divided into individuals, who are real worlds objects, or events, and types, or classes, who are sets of real world objects. Class expressions or definitions gives the properties that the individuals must fulfill to be members of the class. Individuals that fulfill the property are called instances (as in the computing concept).