The quality or state of being edifying; the degree to which something instructs, improves, or uplifts morally or intellectually.
From edifying plus the nounal suffix -ness (expressing state or quality). This abstract noun form allows the concept to be discussed as a measurable characteristic.
Edifyingness is technically valid English but almost never actually used—we'd just say 'how edifying it is' rather than 'the edifyingness of it,' showing how grammar permits words that real speakers never need.
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