In his early epistemological system, which he called Radical Conventionalism, Ajdukiewicz analyzed any
language as a set of expressions or sentences, with inferential
rules of meaning that specify the relation of one expression to another, or to external data. There are three kinds of rules: Axiomatic, Deductive, and Empirical. Following the rules, one can map all knowable sentences of a language. However, some languages' vocabularies can produce
disconnected sentences, which are only partly mapped by the
meaning rules. Therefore, when one uses a language, even scientific one, a
conceptual apparatus, an untranslatable set of meanings, is needed too, and with it a choice of the problems to be settled. For this reason the theory is a form of
conventionalism, and it is radical because even simple experiential reports are exposed to these language-wide considerations. Ajdukiewicz discarded this theory as the 1930s progressed. ==Bibliography==