My dear Uddhava, I have thus explained to you perfect knowledge. There are philosophers, however, who challenge My conclusion. They state that the natural position of the living entity is to engage in fruitive activities, and they see him as the enjoyer of the happiness and unhappiness that accrue from his own work. According to this materialistic philosophy, the world, time, the revealed scriptures and the self are all variegated and eternal, existing as a perpetual flow of transformations. Knowledge, moreover, cannot be one or eternal, because it arises from the different and changing forms of objects; thus knowledge itself is always subject to change. Even if you accept such a philosophy, My dear Uddhava, there will still be perpetual birth, death, old age and disease, since all living entities must accept a material body subject to the influence of time.