A theory of historical discovery: The construction of componential models

Abstract

One of the major goals of 18th century chemistry was to determine the components of substances. In this paper we describe STAHL, a system that models significant portions of 18th century reasoning about compositional models. The system includes a number of heuristics for generating componential models from reactions, as well as error recovery mechanisms for dealing with inconsistent results. STAHL processes chemical reactions incrementally, and is therefore capable of reconstructing extended historic episodes, such as the century-long development of the phlogiston theory. We evaluate STAHL's heuristics in the light of historical data, and conclude that the same reasoning mechanisms account for a variety of historical achievements, including Black's models of mild alkali and Lavoisier's oxygen theory. STAHL explains the generation of competing accounts of the same reactions, since the system's reasoning chain depends on knowledge it has accumulated at earlier stages.

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“…The table also shows the reliability of the questionnaire based on the calculated Cronbach's Alpha (Total: 0.95). (ii) Historical validity: "One way to ensure greater historical validity is to require that a model accounts for a historical sequence of discoveries, rather than isolated events" (Zytkow and Simon, 1986). The proposed model in this research is a result of a series of studies which reveals a historical sequence of findings (e.g.…”

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“…From the standpoint of computational representation, this means that particle reactions can be represented in the same data structures as used in STAHL (Zytkow & Simon, 1986), STAHLp (Rose & Langley, 1986), and GLAUBER (Langley, Simon, Bradshaw & Zytkow, 1987) for the representation of chemical reactions. Moreover, some of the inference rules (e.g., substitution and reduction) used by these systems are also applicable to particle reactions.…”

“…BR-3 differs from STAHL (Zytkow & Simon, 1986), STAHLp (Rose & Langley, 1986), and REVOLVER (Rose & Langley, 1988) in the scope and generality of its goals. The main goal of STAHL and STAHLp is to infer valid reactions and components from their existing knowledge of chemical reactions and componential formulae; belief revision is secondary to their main function.…”

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“…The COPER program also includes abilities above and beyond those of BACON; for instance, it can determine the relevance of a variable even when its values are held constant. Similarly, STAHLp operates in the same domain as Zytkow and Simon's (1986) original STAHL model and uses many of the same heuristics. However, STAHLp also incorporates other heuristics that make it more robust than its precursor.…”