Help strangers who are in trouble

Taking this on as a goal to me will only count as accomplished when I spontaneously do the right thing without being prompted. But I did have this experience of taking a walk in my neighborhood when a woman carrying a gas can came up to me and asked for money to fill up her totally empty car, stranded on the side of the street. I hesitated, but I ended up walking to the gas station with her and gave her some money. I think I did a good thing, but it was entirely self-conscious, and that’s not going far enough for me.

I wonder if the cars I see parked on the side of the highway need my help, and inevitably my deliberation takes too long and I’ve already passed them by. What stops me from responding spontaneously to someone in possible need? Probably the same fear that stops most everyone else in this culture when it comes to strangers.