There are four classes of men, namely karmīs, jṣānīs, yogīs and bhaktas. This statement pertains especially to karmīs and jṣānīs. A karmī tries to he happy within this material world by changing from one body to another. His objective is bodily comfort, either in this planet or in another. When such a person becomes a jṣānī, however, be aspires for liberation from material bondage. Among many such persons who aspire for liberation, one may actually be liberated during his life. Such a person gives up his attachment for society, friendship, love, country, family, wife and children. Among many such persons, who are in the vānaprastha stage, one may understand the value of becoming a sannyāsī, completely accepting the renounced order of life.