Monks would spend much of their time sitting in meditation. Thinking this is the way to enlightenment. Then to be enlightened, would remove them from suffering. Bodhidharma would take a roof tile and start to polish it. The monks asked him what he was doing. Answer was polishing roof tiles to become mirrors. One’s mind can not become enlightened. No more than one can polish a roof tile into mirror. The thinking reinforces the world we live in. Oops, sorry, rambling again.