This document discusses connecting and synchronizing scientific knowledge through an associationist model. It proposes a process model for tracking the evolution of categories in scientific knowledge over time. An example tool called AdvoCate is described that would allow researchers to model changes to categories and maintain connections between changing categories and tools like databases and ontologies. Future work includes formalizing the data model, developing change recognition rules for different category models, visualizing category evolution, and integrating with ontology and database evolution tools.