The state of being perceptive; acumen, discernment, insight(noun)
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Use "perceptiveness" in a sentence
"[T] he film's perceptiveness is frequently bracing, capturing the way starry-eyed proclamations and promises can foreshadow uglier truths, and - as in a sterling underplayed scene - the means by which simple gestures such as asking a girlfriend to call your relatives on your behalf can signal a momentous shift in trust and togetherness."
"Hopefully Tadpole’s perceptiveness is advanced for her age …"
"Sylvanshine's intuitive perceptiveness is melded with the related talent of another character, the ability to count the number of words in any speech or conversation: I've said 2,742 words right now since I started."