The essay examines the proper ends and limits of human knowledge, arguing that natural inquiry must be governed by religion and oriented to practical use. It warns against confusing investigation of created things with discovery of the divine will, criticizes both excessive speculative learning and excessive hostility to exploration, and defends the systematic pursuit of natural philosophy and inventions. The author surveys impediments that arise when sciences are treated in isolation, calls for an inventory of existing inventions and the identification of unmet needs, and proposes guiding principles to shape a disciplined, useful expansion of knowledge.