A man or woman has come to this world. For what? What is his/her task here on earth? S/he will grow day by day. S/he will know, learn many things here. S/he will learn a skill for taking up his/her profession. S/he will get married one day. One day, they will have children. Ultimately, one day, they will become old and die. S/he must think about all of this lifecycle. Because s/he should not be confined or imprisoned or caged by this paltry life (in the sense that life is too short), s/he should think over and over again about life & death. And I believe, this thought must bring some good to the thinker in the long run.