Chapter 3 , titled “Space, Time, and Being” begins a series of five chapters that examine the people and ideas that shaped Ian McHarg’s vision of environmental design. The chapter starts with McHarg’s use of a passage by the Puritan mystic Jonathan Edwards to pose fundamental questions about design and its relationship to observation, inference, and the temporal and material qualities of space. McHarg’s professional collaboration with the architect Louis Kahn in a project (unbuilt) for the Research Institute of Advanced Study situates this discussion within the realm of practice. During this collaboration, McHarg witnessed an experiment in applied science that opened his eyes to a vital but hidden dimension of the landscape that changed the way he read the land and perceived his relationship to it. The chapter sets the stage for McHarg’s subsequent decision to move beyond the spatial confines and material concerns of architectural modernity.