Untangling Rhetoric, Pathos, and Aesthetics in Data Visualization

In contemporary discourse, logos (reason) and, more recently, ethos (credibility) in data communication have been discussed extensively. While the concept of Pathos has enjoyed great interest in the VIS community over the past few years, its connection to similar but relevant concepts like aesthetics and rhetoric remains unexplored. In this paper, we provide definitions of these terms and explore their overlaps and differences in light of their historical development. Examining the historical perspective offers a deeper understanding of how these approaches in science and philosophy have evolved over time, offering a more comprehensive embedding into the design process and its role within it. Drawing from Campbell's seven circumstances, we illustrate how pathos is being used as a rhetorical device in data visualizations today, at times inadvertently.