Common Knowledge
Noun
じょうしき
常識のある人たちばかりで、安心しました。
I was relieved that you guys have common sense.
常識テストを受けてみたが、結果はさんざんだった。
I took a common knowledge test, but my results were terrible.
常識は脇に置いて、少しだけ既存の考えに囚われずに考えてみませんか？
How about putting common sense aside and thinking outside the box for a second?
Normal discerning is the discerning you do on a daily basis, without thinking. It is all the things that you do that are common sense.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.