Old age is the fourth stage. By the time one reaches this stage of his journey, he must have discovered that the joys available in this world are trivial and fleeting. He must be equipped with the higher knowledge of spiritual joy, available through delving into the inner spring of Bliss. Through his experiences, his heart must have softened and be filled with compassion. He has to be engrossed in promoting the progress of all beings without distinction. And he must be eager to share with others the knowledge he has accumulated and the benefit of his experiences.