I believe that this is saying that our thought process is derived from what we believe in. It is how we perceive things should or shouldn't be. However, what is physically present is an illusion to the values that are instilled in us by parents and other authority figures. The physical is not neccesary what we want to happen but it is what we believe should happen. Thus, making our thoughts the real answer and the physical action an illusion to hide our real thought process.