Pragmatic theory of information
The pragmatic theory of information (PTOI) is a set of concepts and principles for defining, measuring, and tracking the time evolution of information. PTOI is derived from Charles Sanders Peirce's general theory of signs and inquiry. Peirce explored a number of ideas about information throughout his career. One set of ideas is about the "laws of information" having to do with the logical properties of information. Another set of ideas about "time and thought" have to do with the dynamic properties of inquiry. All of these ideas contribute to the pragmatic theory of inquiry.
Peirce set forth many of these ideas very early in his career, periodically returning to them on scattered occasions until the end, and they appear to be implicit in much of his later work on the logic of science and the theory of signs, but he never developed their implications to the fullest extent.
More recently, Edward D. Weinberger formulated a quantitative theory of pragmatic information. In contrast to standard information theory that says nothing about the semantic content of information, Weinberger's theory attempts to measure the amount of information actually used in making a decision. Included in Weinberger's paper is a demonstration that his version of pragmatic information increases over the course of time in a simple model of evolution known as the quasispecies model. This is demonstrably not true for the standard measure of information.
- Weinberger, Edward D. (2002), "A Theory of Pragmatic Information and Its Application to the Quasispecies Model of Biological Evolution", BioSystems 66 (3), 105–119. Eprint.