This section focuses on books about the calculation and representation of time and space in fields including geometry, astronomy, anatomy, art history, theology and criminology. In particular, it examines how book forms such as illustrations, pop-ups, foldouts and volvelles helped the reader to think beyond the two-dimensional space of the page, in order to apprehend unfamiliar spatial and temporal forms and even to participate in complex spatio-temporal processes. Books about measurement by nature evoke a world of reference and utility outside the book. It is not surprising, then, that many of them seem to exceed their own material bounds, whether through foldouts that quadruple the spatial dimensions of the page or by paper constructions (pop-ups) that convert the page from a two- to three-dimensional object. With such books, use means practice in the most explicit sense, since their readers are asked to use their hands to manipulate the matter of the book in order to apprehend it and so (often literally) unfold knowledge.
Some of these books attempt to give the reader access to things not usually evident, to secrets and hiding places, to the interior of the body, to the elusive space of the psyche. Books on the art of memory are important here, since they aimed both to construct and expose such places, instructing readers to visualize in spatial terms both the contents of their memories and the temporality of the memory process itself.
With material features that enabled readers to move, materially and conceptually, between different dimensions, all of these books from the mathematical and human sciences positioned themselves as models for the mind at work.