Conjectures and manipulations: External representations in scientific reasoning

Abstract

What I call theoretical abduction (sentential and model-based) certainly illustrates much of what is important in abductive reasoning, especially the objective of selecting and creating a set of hypotheses that are able to dispense good (preferred) explanations of data, but fails to account for many cases of explanations occurring in science or in everyday reasoning when the exploitation of the environment is crucial. The concept of manipulative abduction is devoted to capture the role of action in many interesting situations: action provides otherwise unavailable information that enables the agent to solve problems by starting and performing a suitable abductive process of generation or selection of hypotheses. Many external things, usually inert from the epistemological point of view, can be transformed into what I call epistemic mediators, which are illustrated in the last part of the paper, together with an analysis of the related notion of “external representation”. Finally, some examples of computational programs that simulate geometrical reasoning are illustrated. The computational embodiment generates a kind of “squared” epistemic mediator: geometrical construction, as an example of epistemic mediator, is further mediated.