In modern times, speaking to a woman you don’t know causes you negligible risk, even if it doesn’t go well. In a city of millions, you are unlikely to see this person ever again. Yet the primitive part of your mind still perceives this action as dangerous, as socially inappropriate. Your mind sends you signals: “This isn’t safe. You’re jeopardizing your position in the group.” Your mind is efficiently inhibiting a behavior that is seen as a threat to your survival. And you have no control over this reaction.
