Over on Less Wrong, there is a wiki article about the Dark Arts. This is any form of persuation that takes advantage of a person’s cognitive biases to get them to do what you want them to do.
I’ve read a bit about cognitive science, and “hacking” my own brain to become more aware of my own biases seems like, at the least, harmless fun and at the most a massive supporting beam in the skyscraper of my self-improvement. However, there’s another side to that: Knowing that your own cognitive biases are also present in other people. It’s only a short leap to go from not telling people about those biases and simply using their own ignorance of their brainware to your advantage.
Yudkowsky’s allusion to the Dark Side of the Force seems apt.
For example, you can prime people to land on an answer you want by making them decide on something else totally unrelated. If you ask someone to tell you how many letters there are in some sentence, and then later ask them to guess how many countries are in Africa, they’ll guess a number pretty close to how many letters there are in the unrelated sentence.
That is a very simple, harmless application of brain-hacking. But what about more nefarious things? You could probably use something like the availability heuristic to scare someone or fool them into taking a position you currently hold or favor. I kinda did this to myself; a friend of mine is in Afghanistan and I would always read stories about all of the craziness going on over there, needlessly worrying myself.
On the other hand, I made it a point to not mention to her how bad sexual harrassment and rapes are over in Afghanistan with her being an attractive girl. She actually did ask me what I thought about her going over there, telling me how important it was that she go there to advance her career, so mentioning that might have scared her more than necessary. I’m ex-military, so I’ve had more briefings about how problematic sexual harrassment is over in theater than I can remember. But then again, that in and of itself might be an availability heuristic that the military forced on us guys to make us more cognizant of it!
Another example, I was trying to teach an ex-gf of mine about cold reading and how that plays into the leaps in inference that the brain makes. What brought this up was that she thought that astrology tapped into some sort of evil energy and I rejoined that no, astrology is bullshit because it’s a cold reading technique. So I did a little cold reading game on her, and she seemed a bit startled about how “accurate” it was. There’s one point in the cold read game where I describe her “ideal boyfriend”, and it would have been easy for me to manipulate the cold read to say “wow, your ideal boyfriend sounds like me!” but I didn’t do that since it seemed to be an abuse of my powers, so to say (especially with her being my ex and all).
Some further reading: http://lesswrong.com/lw/9iw/the_dark_arts_a_beginners_guide/