Lines of Thought: Branching Diagrams and the Medieval Mind, Hardcover

We think with objects--we conduct our lives surrounded by external devices that help us recall information, calculate, plan, design, make decisions, articulate ideas, and organize the chaos that fills our heads. Medieval scholars learned to think with their pages in a peculiar way: drawing hundreds of tree diagrams. Lines of Thought is the first book to investigate this prevalent but poorly studied notational habit, analyzing the practice from linguistic and cognitive perspectives and studying its application across theology, philosophy, law, and medicine.

These diagrams not only allow a glimpse into the thinking practices of the past but also constitute a chapter in the history of how people learned to rely on external devices--from stone to parchment to slide rules to smartphones--for recording, storing, and processing information. Beautifully illustrated throughout with previously unstudied and unedited diagrams, Lines of Thought is a historical overview of an important cognitive habit, providing a new window into the world of medieval scholars and their patterns of thinking.

About author(s):Ayelet Even-Ezra is a senior lecturer in the History Department at the Hebrew University of Jerusalem. She is the author of Ecstasy in the Classroom: Trance, Self, and the Academic Profession in Medieval Paris and her articles have appeared in Harvard Theological Review, Traditio, and the Journal of Ecclesiastical History, among many other publications.