Title: Communication in Tarski, Possible World and Situation Semantics

Author: Eric Werner, Ph.D.

Contact: eric.werner@cellnomica.com


We present a minimal theory of communication for agents in a social setting. We then compare our theory with Tarski semantics, Kripke's possible worlds semantics and situations semantics. The strengths and weaknesses of each theory is analyzed.


One of the fundamental functions of language is to communicate information about situations in the world. The reason there is any need to communicate at all is that we need information to act. Action or the possibility of action presupposes information. We need that information because of our universal epistemic position. We know very little about the state of the world. Our only access to the real state is by way of perception and communication. Perception gives us direct access (of a sort). Communication gives us indirect access by way a link or series of links to someone who has direct access through perception. Communication in this sense extends our perceptual field potentially to the range of perception of the entire linguistic community. Communication extends perception from the intra personal to the interpersonal sphere.

Although the world is constant enough to permit the invariencies necessary for the very possibility of perception and communication, the world changes enough that were it not for perception and communication, our functional knowledge about the state of the world would quickly degenerate into total uncertainty. Perception and communication keep this uncertainty from exploding.

Information and uncertainty stand in an inverse relationship. The greater (less) the information we have, the less (greater) is the uncertainty. Communication if it is non redundant will increase our information and decrease our uncertainty.

The communicative act leaves the world beyond the speakers practically unchanged. Rather the uncertainty of the recipient of the information is changed. (Assuming, for the present, that the recipient accepts the message and the message is non redundant.) The uncertainty is reduced or, equivalently, the information the recipient has about the world has increased. Let us call this state in the subject that changes as his uncertainty or information about the world fluctuates, the subject's information state I. The information state is a part of the larger representational state R realized in the mind-brain of the subject.