Minerva is a collaborative effort between communication designers and humanities scholars in understanding how information visualizations can support philosophical historiography studies. Proceeding through a concrete case study, we present an investigative process that has led to a first iteration prototype of a digital tool for the exploration and the interpretation of large text corpora combining term frequency visualizations with text annotations. What distinguishes this project from more traditional approaches to text analysis and visualization in the digital humanities is its foundation on an open-ended and collaborative experimentation rather than on a requirements- driven development. As part of a broader research project, this work aims also at exploring opportunities and challenges of bringing together scholars, designers, and computer scientists in the definition of novel research practices in the humanities, involving data visualizations and rich graphical interfaces.