Evolving natural kinds

Abstract

Abstract This chapter elucidates the nature and role of ‘truth-conducive conditionals-supporting inferences’ over time, seeing these inferences as joining the dots among modally robust phenomena and their lawlike dependencies. It is this inferential game that ultimately underpins the Neurathian strategy of NKHF. To illustrate this point, the chapter delves into an example taken from the history of the electron. It reconstructs how J.J. Thomson arrived at the identification of the charge-to-mass ratio for what he called a ‘corpuscle’ working on cathode rays around 1897 and the role of situated epistemic communities including glass-blowers and kelp-makers behind this discovery (Section 10.2). It turns then to a different perspective within which Grotthuss and later Helmholtz and others were studying the phenomenon of electrolysis (Section 10.3). And it briefly examines the influential treatment of the electric charge as a natural unit by Planck and the emerging quantum perspective (Section 10.4). These historical details feed into the philosophical analysis in the rest of the chapter, which returns to the notion of perspectival models as inferential blueprints and modally robust phenomena (Section 10.5). It illustrates how Grotthuss’s chain model and Thomson’s model of the Faraday tubes acted as inferential blueprints to support truth-conducive conditionals-supporting inferences. Section 10.7 zooms into the details of one such chain of conditionals-supporting inferences. The division of modal labour between indicative and subjunctive conditionals described in Chapter 5 is here applied to tease out and exemplify how our knowledge that there is an electric charge is the outcome of epistemic communities across scientific perspectives engaging in an inferential game of asking for reasons as to why any particular grouping of phenomena hangs together.