"Learned ignorance," the recognition that God is beyond us and our knowing capacities is the theological concept for which Nicholas of Cusa is most famous. Despite God's apparent absence Nicholas offers original ways to think about God that would unite his presence with his absence. He called these proposals "conjectures" (coniecturae). Conjecture and conjecturing are central to the methodology of Nicholas's philosophical theology and to his thinking about human knowledge.

By using concrete examples from the everyday life of his times as symbolic imagery Nicholas makes what we say about God imaginatively available and theoretically plausible. He called such conjectural symbols "aenigmata" (= "symbolic or 'enigmatic' conjectures") because they partially clarify and likewise point to an exact truth that is beyond us. Novel and imaginative, Nicholas's conjectural examples break with the traditional medieval Aristotelian examples and provide further evidence of his role as a figure bridging medieval and Renaissance thought.

Following his earlier book, Reading Cusanus (The Catholic University of America Press, 2003), Clyde Lee Miller here examines and comments on the meaning of "conjecture" in Nicholas of Cusa. The Art of Conjecture: Nicholas of Cusa on Knowledge explores what Nicholas meant by conjecture and its import as demonstrated in his treatises and sermons. Beginning with Nicholas' On Conjectures, Miller analyzes a series of conjectural symbols and proposals across Nicholas's less frequently discussed texts and recently published sermons. This early Renaissance thinker offers an original and ground-breaking way of framing speculation in philosophical theology and more generally in philosophy itself.