Styles of Reasoning: Analysis:Synthesis and Palaetiology is book examines Londoners using two di erent styles of reasoning in the life sciences between 1820 and 1858. e simplest way to tell this story is to focus on one style and then on the other. is does not result in an overly schematic history, if by this term one denotes a rigid and arti cial set of historiographic structures. One reason is because of the agents’ own self-descriptions and practices. Many researchers explicitly described themselves as practising one style or the other. In other cases, although they did not openly describe themselves as practising one style, researchers’ methods and practices clearly show a use of one common style or the other, and this is duly noted. In still other instances a researcher would appropriate what he liked from another’s work and reinterpret it according to his own style of reasoning. A less charitable reading is that others’ work could be deliberately misinterpreted. ose still concerned with matters of agency and structure can turn to the conclusion of this work for an extended discussion.