Chemical “Substances” That Are Not “Chemical Substances”

Abstract

The main scientific problems of chemical bonding were solved half a century ago, but adequate philosophical understanding of chemical combination is yet to be achieved. Chemists routinely use important terms (“element,” “atom,” “molecule,” “substance”) with more than one meaning. This can lead to misunderstandings. Eliminativists claim that what seems to be a baseball breaking a window is merely the action of “atoms, acting in concert.” They argue that statues, baseballs, and similar macroscopic things “do not exist.” When macroscopic objects like baseballs move, exceedingly large numbers (∼1025) of microscopic components coordinate their activities. Understanding how this happens requires attention to the interactions that link parts into larger units. Eliminativists say that everything that truly exists has causal relationships in addition to those of its components—“nonredundant causality.” This paper holds that if a number of entities interact in such a way that the effect of that collection on test objects is different than it would have been in the absence of the interaction, then identification of that collection as a single composite agent is warranted, for purposes to which that difference is relevant. Ordinary “chemical substances” (both elementary materials such as dihydrogen and compounds such as water) fulfill this version of the requirement of nonredundant causality. Other sorts of chemical coherences, including chemical dissipative structures (e.g., flames), also fulfill that criterion. All these types of coherences qualify as “substances” (as that term is used in philosophy) even though they are not all “chemical substances.”