Architectura civil recta y obliqua (1678–79), by the Cistercian Juan Caramuel de Lobkowitz (1606–82), is one of the most important Spanish architectural treatises of the seventeenth century. The work was published in three volumes, and until recently, scholars knew of an unpublished fourth volume, Architectura natural, only through a fragment of sixty pages titled Compendio de architectura natural. In her Findings article Architectura natural, the Unpublished Fourth Volume of Juan Caramuel’s Seventeenth-Century Architectural Treatise, Maria Elisa Navarro Morales presents more than two hundred manuscript pages unearthed at the episcopal archive in Vigevano. This research not only proves that Caramuel intended to publish an additional volume but also critically expands our knowledge of his treatise by underscoring the vital importance of an understanding of the natural world for architectural education. This challenges our contemporary emphasis on professional specialization and invites us to rethink how architecture was viewed in the early modern world.