Francis Bacon's earliest surviving natural philosophical treatise (composed circa 1603) bears the title Valerius Terminus of the Interpretation of Nature. This study, resting on fresh attention to the surviving authorial manuscript, has three goals. It begins by identifying a lost precursor work apparently entitled "Of Active Knowledge." It then examines the significance of the pseudonyms Bacon chose to introduce his ideas, considering especially his invocation of Erasmus's emblem, the Roman deity Terminus. Finally, it shows how the Valerius Terminus's global vision of contemporary knowledge ultimately helped shape the iconography of Bacon's published Instauratio magna.