Common Sense
Common Knowledge
noun
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.
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.
常識がない人との付き合いはストレスです。
Dealing with people who lack common sense is stressful.
常識的に考えれば、その計画は成功しないだろう。
Common sense suggests that the plan won't succeed.