I think probably all of you have experienced this from time to time. We're in meditation and all of the sudden the thought comes up, we're going to kill somebody, or we're planning to rob a bank and how perfect we can do it and all these different things. Where do they come from? How many movies did you see, how many TV shows did you see, how many stories did you read about? For a lot of people that's exactly where the thoughts come from. And it's just a thought, and the way to react is just to note them, let them go, but I'd add more than that, especially if it's a dream. I wake up from a dream in which I'm a so-called villain, or simply doing something I don't really want to do, that's another time I do Compassion/ Lovingkindness straight away. You've all been told that if you have a nightmare to do it, to me waking up from a dream where I did something I don't want to do is like a nightmare. I don't scream and all, but it's just - I don't want that! That is not what I want to do, that is not what I want to be, that is not a condition that I want. So when I wake up from a dream of that sort I'll immediately do Compassion/ Lovingkindness to everybody in the dream, to me, and to people around the world who are having a similar dream.
So sometimes you may do it when you're sitting in meditation. Personally I don't get this much anymore, but when I was younger, yeah, I could plan a perfect crime. I played enough games with my brother, cops and robbers and this and that, watched enough cop shows, so sometimes in meditation my mind would plan perfect crimes. As soon as you become aware, oh my gosh, I don't do that, note it and do Compassion/Lovingkindness for it, and then come back to your meditation subject. See it just as conditioning, it's just in there because you grew up with it, you put those thoughts in there, you watched enough shows, read enough books, magazines, and now you've got to work with it.
On top of learning how to let it go, you must work with all the Four Great Efforts. Letting it go is one of the Four Great Efforts, preventing is another great effort. How's this person going to prevent these unwise thoughts? How are you going to prevent them if you've got any of them? You're going to have to stop putting them in. Stop putting in violent movies or whatever else that will lead you to sitting in meditation just having those sorts of thoughts.