_ Convention_ was immediately recognized as a major contribution to the subject and its significance has remained undiminished since its first publication in 1969. Lewis analyzes social conventions as regularities in the resolution of recurring coordination problems-situations characterized by interdependent decision processes in which common interests are at stake. Conventions are contrasted with other kinds of regularity, and conventions governing systems of communication are given special attention.

This dissertation examines the functional roles symbols play in biological organisms, scientific models and adaptive learning devices, analyzing the process of how symbols acquire new functions. The semiotic categories of syntactics, semantics, and pragmatics are used to examine the functioning of symbols in organisms, models, and devices. The dissertation explores how we would go about designing self-organizing devices which adaptively construct their own relationships to the physical world . It bears on the frame/feature-generation problem in artificial intelligence, the problem of (...) machine creativity in philosophy, the measurement problem in physics, the problem of generating new observables in science, and the problem of emergent functions in evolutionary biology. Much of the perspective comes out of the work of theoretical biologists Howard Pattee and Robert Rosen. ;An analytical framework is developed for distinguishing between computation, measurement, control, and nonsymbolic functionalities. A taxonomy of adaptive cybernetic devices is proposed in which nonadaptive devices are distinguished from computationally adaptive ones and semantically adaptive ones . Evolutionary devices adaptively construct their own sensors and effectors contingent upon their performance, and are thus qualitatively different from devices now in use. Evolutionary devices are analogous to the biological evolution of new sense and effector organs. Relative capacities and limitations of the device types are outlined. ;Three contemporary conceptions of emergence are distinguished: computational emergence, thermodynamic emergence, and emergence-relative-to-a-model. Levels of adaptivity are connected to types of emergence. ;Throughout, purely computational, logic-driven strategies for generating new functions are criticized as being incapable of generating new primitives. It is argued that computers have completely nonemergent behavior because of their completely specified, digital, symbolic nature, while biological organisms are capable of emergent behavior because they also include analog, nonsymbolic processes. An evolutionary robotics research program is suggested as an alternative to purely computational approaches. (shrink)

The final version of the paper is published pp. 117-166 in: Myrdene Anderson and Floyd Merrell (eds.): On Semiotic Modeling . Mouton de Gruyter, Berlin and New York, 1991.

A new conceptual framework is proposed to situate and integrate the parallel theories of Turchin, Powers, Campbell and Simon. A system is defined as a constraint on variety. This entails a 2 × 2 × 2 classification scheme for “higher‐order” systems, using the dimensions of constraint, (static) variety, and (dynamic) variation. The scheme distinguishes two classes of metasystems from supersystems and other types of emergent phenomena. Metasystems are defined as constrained variations of constrained variety. Control is characterized as a constraint (...) exerted by a separate system. The emergence of hierarchical systems is motivated by evolutionary principles. The positive feedback between variety and constraint, which underlies the “branching growth of the penultimate level,” leads to the interpretation of metasystem transitions as phases of accelerated change in a continuous evolutionary progression toward increasing variety. The most important MSTs in the history of evolution are reinterpreted in this framework: mechanical motion, dissipative structuration, life, multicellular differentiation, sexuality, simple reflex, complex reflex, associating, thinking, metarationality and social interaction. (shrink)