What's the noun for idealness? Here's the word you're looking for.
idealism
The property of a person of having high ideals that are usually unrealizable or at odds with practical life.
The practice or habit of giving or attributing ideal form or character to things; treatment of things in art or literature according to ideal standards or patterns;—opposed to realism.
(philosophy) An approach to philosophical enquiry, which asserts that direct and immediate knowledge can only be had of ideas or mental pictures.
“Orwell was indeed unsociable, anti-feminist and homophobic, but only ambiguously anti-Semitic, and by no means such a dewy-eyed idealiser of the plebs as some have imagined.”
“We must break past idealizations of community and embrace what is before us.”
“As idealizations, they appear to be predicated on normative but contradictory and ultimately irreconcilable understandings of excellence.”
“Such implausible idealizations, then as now, go hand in hand with nostalgia for the lost or vanishing world of the Gael as initially evoked by ethnographic prefaces.”