The memory that always comes to my mind is when I first started being interested in sex when I was about 11 or 12. If I were thinking about it in public, I'd think the people around me knew what I was thinking. So, I'd try to suppress the thoughts. Maybe that's what underlies the problem - having thoughts we feel ashamed of.

Aside from the fact that I now know people can't read other people's mind, I no longer feel ashamed of any of my thoughts. They're not all nice, but they're just thoughts. When you understand that they can't control you and they don't mean you're a bad person, you can just let them go. If they scare you for some reason, they tend to hang around longer because you're engaging with them.

Sometimes it seems like someone is "reading your mind," because you have a thought or memory come into your head, then they suddenly mention the same thing. It always comes back, in my experience, to the fact that something in the external environment cued the same thought in both of you. It can feel kind of freaky when it happens, though.

Sometimes people just "know" what we're thinking, because we're thinking the same thing they'd be thinking in our shoes. Our brains are just set up to let us understand the other guy's emotions, to empathize.