Knowledge is key to this, but it's not enough. Some people will try to fool you, and then knowledge will help you decide whether that is the case. It may be a cultural thing you haven't picked up on.

If I came across a case of taharrush gamea, Heaven help me. I believe I would turn out a killer. If I came across some guy not being able to tell me he's late with a delivery; I understand it, but to him it's a loss of face? Of course I try to help.

I can't believe defending those in an exposed situation is a bad thing. The thing is: One has to be able to trust oneself without some sort of nonsensical, theoreticsl framework.