Epistemic Mediators and Chance Morphodynamics

The recent epistemological and cognitive studies concentrate on the concept of abduction, as a means to originate and refine new ideas. Traditional cognitive science and computational accounts concerning abduction aim to illustrate discovery and creativity processes in terms of theoretical and “internal” aspects, by means of computational simulations and/or abstract cognitive models. We will illustrate in this papercognitive models. We will illustrate in this paper that some typical internal abductive processes are involved in chance discovery and production (for example through radical innovations). Nevertheless, especially concrete manipulations of the external world constitute a fundamental passage in chance discovery: by a process of manipulative abduction it is possible to build prostheses (epistemic mediators) for human minds, by interacting with external objects and representations in a constructive way. In this manner it is possible to create implicit knowledge through doing and to produce various opportunity to find, for example, anomalies and fruitful new risky perspectives. This kind of embodied and unexpressed knowledge holds a key role in the subsequent processes of scientific comprehension and discovery. The paper describes some of the “templates” of manipulative behavior which account for the most common cognitive and epistemic acting related to chance discovery and chance production. The last part of the paper is devoted to illustrate chance discovery from the perspective of dynamical systems. Chance discovery and production can be viewed as a kind of event related to the transformations of the attractors responsible of the cognitive system performances. Theoretical and Manipulative Reasoning Science is one of the most explicitly constructed, abstract, and creative forms of human knowledge. In the twentieth century Kuhnian ideas about irrationality of conceptual change and paradigm shift (Kuhn 1962) brought philosophers of science to distinguish between a logic of discovery and a logic of justification, and to the direct conclusion that a logic of discovery, and then a rational model of discovery, cannot exist. Today researchers have by and large abandoned this attitude by concentrating on the concept of abduction pointed out by C.S. Peirce as a fundamental mechanism by which it Copyright c 2002, American Association for Artificial Intelligence (www.aaai.org). All rights reserved. is possible to account for the introduction of new explanatory hypotheses in science. Abduction is the process of inferring certain facts and/or laws and hypotheses that render some sentences plausible, that explain or discover some (eventually new) phenomenon or observation; it is the process of reasoning in which explanatory hypotheses are formed and evaluated. There are two main epistemological meanings of the word abduction (Magnani 2001): 1) abduction that only generates “plausible” hypotheses (“selective” or “creative”) and 2) abduction considered as inference “to the best explanation”, which also evaluates hypotheses. To illustrate from the field of medical knowledge, the discovery of a new disease and the manifestations it causes can be considered as the result of a creative abductive inference. Therefore, “creative” abduction deals with the whole field of the growth of scientific knowledge. This is irrelevant in medical diagnosis where instead the task is to “select” from an encyclopedia of pre-stored diagnostic entities. Theoretical abduction1 certainly illustrates much of what is important in creative abductive reasoning, in humans and in computational programs, but fails to account for many cases of explanations occurring in science when the exploitation of environment is crucial. It fails to account for those cases in which there is a kind of “discovering through doing”, cases in which new and still unexpressed information is codified by means of manipulations of some external objects (epistemic mediators). The concept of manipulative abduction2 captures a large part of scientists thinking where the role of action is central, and where the features of this action are implicit and hard to be elicited: action can provide otherwise unavailable information that enables the agent to solve problems by starting and by performing a suitable abductive process of generation or selection of hypotheses. Many attempts have been made to model abduction by developing some formal tools in order to illustrate its comMagnani (Magnani 2001; 2002a) introduces the concept of theoretical abduction. He maintains that there are two kinds of theoretical abduction, “sentential”, related to logic and to verbal/symbolic inferences, and “model-based”, related to the exploitation of internalized models of diagrams, pictures, etc., cf. below in this paper. Manipulative abduction and epistemic mediators are introduced and illustrated in (Magnani 2001). putational properties and the relationships with the different forms of deductive reasoning (Bylander et al. 1991). Some of the formal models of abductive reasoning are based on the theory of the epistemic state of an agent (Boutilier & Becher 1995), where the epistemic state of an individual is modeled as a consistent set of beliefs that can change by expansion and contraction (belief revision framework). These kinds of logical models are called sentential (Magnani 2001). They exclusively deal with selective abduction (diagnostic reasoning)3 and relate to the idea of preserving consistency. Exclusively considering the sentential view of abduction does not enable us to say much about creative processes in science, and, therefore, about the nomological and most interesting creative aspects of abduction. It mainly refers to the selective (diagnostic) and merely explanatory aspects of reasoning and to the idea that abduction is mainly an inference to the best explanation (Magnani 2001).