Improbability and Novelty of Descriptions

In this chapter we define the information of an event A ∈ Σ, or in our terminology the novelty of a propositionA as \({-\log }_{2}p(A)\). We further define the important new concept of a description and extend the definition of novelty from events to descriptions. Finally we introduce the notions of completeness and directedness of descriptions and thereby the distinction between surprise and information, which are opposite special cases of novelty.