 The description of logical constructions as “incomplete symbols” derives from the use of contextual definitions that provide an analysis or substitute for each sentence in which a defined symbol may occur. The definition does not give an explicit definition, such as an equation with the defined expression on one side that is identified with a definiendum on the other, or a universal statement giving necessary and sufficient conditions for the application of the term in isolation. The connection between being a fiction and expressed by an “incomplete symbol” can be seen in Russell’s constructions of finite cardinal and ordinal numbers by means of the theory of classes. That “no-classes” theory, via the contextual definitions for class terms, makes all the numbers “incomplete symbols”, and so numbers can be seen as “logical fictions”.