The spirit-world is incomprehensible to the mind which is only acquainted with the laws of the physical world. An individual who is a limited being here, is like a world there; a soul is a person here and a planet there. When one considers the helplessness of this plane, one cannot for a single moment imagine the greatness, the facility, the convenience, the comfort, and the possibilities of the next world; and it is human nature that that which is unknown to man, means nothing to him. A pessimist came to Hazrat Ali and said, 'Is there really a hereafter for which you are preparing us by telling us to refrain from things that we desire, and to live a life of goodness and piety? What if there is no such thing as a hereafter?' Ali answered, 'If there is no such thing as a hereafter, I shall be in the same situation as you are; but if there is a hereafter, then I shall be the gainer, and you will be the loser!' Life lives and death dies; the one who lives will live, must live; there is no alternative.