To make certain types of spiritual progress we have to fool the demons, divert the mischevious elementals. There are many ways to do this. One of the best, if you wish to empty the mind of thoughts, it to fill the mind with thoughts. How can this be? After all, you might say, the mind is already full of thoughts and that doesn’t empty it now. The trick is to fill the mind with thoughts that aim at emptiness. You focus on your breathing, and projections into the future and the past disappear. You decide to really feel the moment and worries evaporate. Thoughts can be used to refine thinking itself. This is one of the goals of Qigong.