 The possible world interpretation of modal operators (Kripke 1959) is related to the notion of “state description” introduced by Carnap (1947). A state description is a conjunction that contains exactly one of each atomic sentence or its negation (see  section 4.3).  The ambition to define a good probability measure for state descriptions was one of the motivations for Solomonoff (1960, 1997) to develop algorithmic information theory. From this perspective Kolmogorov complexity, with its separation of data types (programs, data, machines) and its focus on true sentences describing effects of processes is basically a semantic theory. This is immediately clear if we evaluate the expression: