This isn't exactly meditation - it's thinking with your eyes closed. That isn't to say it's bad or that you shouldn't do it, but you can do the suggested exercises outside the context of meditation. Focusing on thoughts and ideas is the opposite of traditional Buddhist meditation, where the ultimate goal is to realize the horrifying truth that "you" don't exist, aka enlightenment. Ramana Maharshi might be a good person to investigate.
edit: thank god this was spam-banned from front page