Agnoiology (from the Greek ἀγνοέω, meaning ignorance) is the theoretical study of the quality and conditions of ignorance,[1][2] and in particular of what can truly be considered "unknowable" (as distinct from "unknown").
The term was coined by James Frederick Ferrier, in his Institutes of Metaphysic (1854),[3] as a foil to the theory of knowledge, or epistemology.
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