Abstract

Is chemistry primarily about things or about processes, about chemical substances or about chemical reactions? Is a chemical reaction defined by the change of certain substances, or are substances defined by their characteristic chemical reactions? What appears to be a play on words to the modern scientist, is actually one of the most fundamental ontological question since antiquity, prompted by the most radical change – the chemical change or the ‘coming-to-be and passing-away’ as Aristotle’s treatise on theoretical chemistry came to be known. The question has bothered philosophers ever since, who were not satisfied with the much too simplistic answer of atomism, according to which the basic elements of nature are atoms.