'empiricalness' originates from English, specifically from the adjective 'empirical' plus the noun-forming suffix '-ness', where 'empirical' ultimately comes from Greek 'empeiria' (via Late Latin 'empiricus') meaning 'experience'.

'empirical' developed from Greek 'empeiria' → Late Latin 'empiricus' → Medieval/Modern Latin and then into English as 'empirical'; the modern noun 'empiricalness' arose in English by adding the suffix '-ness' to form a noun meaning 'the quality of being empirical'.

Initially it meant 'pertaining to experience' (as an adjective); over time, with the addition of '-ness', it evolved into the noun meaning 'the quality or condition of relying on observation/experience'.