Proposition

A proposition is defined as "a grammatically structured combination of concepts to identify a subject by a process of measurement inclusion."

The value of any tool lies in its use. What concepts are used to do is to identify: to state in words what something is. The form in which we make conceptual identifications is the proposition.^[1]

According to Rand:

Since concepts, in the field of cognition, perform a function similar to that of numbers in the field of mathematics, the function of a proposition is similar to that of an equation: it applies conceptual abstractions to a specific problem.^[2]

This analogy highlights that just as equations apply mathematical abstractions to solve specific problems, propositions apply conceptual abstractions to identify specific Fact about reality.

A proposition must be distinguished from the sentence used to express it. A sentence is a series of words; the proposition is the cognitive content of the sentence, distinguished from its linguistic form.(More technically, a proposition represents the form of a judgment, in abstraction from whether one is asserting it, denying it, considering it, etc.)

Propositions can be general or specific. Specific propositions describe individual instances (e.g., "This chair is made of wood"), while general propositions (or generalizations) apply to all instances within a class (e.g., "A chair is man-made"). The process of forming generalizations involves identifying essential characteristics common to all instances of a concept while omitting non-essential measurements.