Signs, search and communication: Towards an empirical future for semiotics -- I SIGNS AND REPRESENTATIONS -- Semiosis, cognition, interpretation -- A triadic theory of perception -- Systems of logical representation and inference: An empiricist approach to cognitive science -- Semiotic primitives and conceptual representation of knowledge -- Semiotic aspects of neurally based representation of knowledge -- II ABDUCTION AND REASONING IN EXPERT SYSTEMS -- Human-like reasoning under uncertainty in expert systems -- Abduction: The creative process -- Expert systems and the abductive circle -- Can machines compensate for biased human reasoning? Case studies in medical decision making -- Procrustes, or the future of flexibility -- III COMMUNICATION WITH EXPERT SYSTEMS -- Believing, causing, intending: The basis for a hierarchy of sign concepts in the reconstruction of communication -- On knowledge representing interacting systems -- Implementing a sense of time in intelligent systems -- Towards an evaluation tool for natural language interfaces -- The linguistic analysis of expert texts -- Cooperative human-machine reasoning: Communication through the user interface -- Name index -- Subject index -- Addresses of the authors.