Abstract

Sir Benjamin Collins Brodie’s Calculus of Chemical Operations (1866, 1877) proposed a new way of representing chemical substances and operations using the language of symbolic algebra. It claimed independence of any ontological commitment, particularly as regards the reality of atoms and molecules. It has been of interest to historians and to those interested in nineteenth-century debates about the atomic theory. This paper revisits Brodie’s epistemology, challenging the received view that Brodie’s was primarily a philosophic project. It will propose a new interpretation of the Calculus, based upon an examination of Brodie’s previous work as a chemist. It will be argued that a central goal of the Calculus was to justify a new theory of the elements, and that Brodie hoped to use this to ground a classification scheme that could embrace all chemical substances. Like a biological taxonomy this grand ordering would demonstrate the actual plan of nature. Had he succeeded, it might have fulfilled a project pursued previously by Charles Gerhardt.