I would like to know what 事柄 adds to the sentence in terms of nuance (instead of more generic expressions such as こと、or もの, ...)
The context is of a veteran police inspector giving some advice to a new recruit on her first case.
あんたが教わってきた事柄は全て理詰めのセオリーだ それがどれだけ無意味なもんか すぐに思い知る羽目になるだろさ まあ覚悟だけはしておくんだな
Everything you've been taught is based on theories and logic. Soon, you'll likely come to realize how pointless they are. Well, at least be prepared.