Abstract

This paper analyzes features of the emergence of new fields in science by examining the cases of cytology and biochemistry. The first step in the emergence of these new fields was the discovery of a new entity. A subsequent claim was made that entities of this kind are found more generally; making this generalization constituted the construction of a new theory. As a line of research to test the theory began, a new domain was formed and the new field emerged. In each case the theory proposed a new solution to an old problem in science. Some implications of this analysis for understanding the emergence of other fields are indicated.