The same knowledge can be utilized for finding out God. That is mahātmā. This is the difference. You may have some particular knowledge. Suppose you are expert singer. Very good. But if you earn your money for fulfilling your sense desires, that is demonic. But you know the art, how to sing. If you very melodiously sing Hare Kṛṣṇa mantra, then you are demigod. The same thing can be utilized both ways. Anything. Therefore śāstra says, idaṁ hi puṁsas tapasaḥ śrutasya vā (SB 1.5.22). People are advancing by research and by education. Śrutasya. Śrutasya means education, and tapasaḥ, and. . . To become very learned scholar, scientist, it requires tapasya, austerities, penance. It is not that all of a sudden one becomes very great scientist. After many, many research work. Therefore it is called tapasaḥ. Idaṁ hi puṁsas tapasaḥ śrutasya vā sviṣṭasya sūktasya ca buddhi-dattayoḥ (SB 1.5.22). People do very pious activities, charity, munificence. Now, what is the purpose? What is the purpose of becoming educated, learned scholar, very charitable and all these pious activities? What is the end? Ask them. Somebody will say, those who believe next life—that is also fact—that "Next life also I will get opulence, properly situated." That is also fact.
But we Vaiṣṇava philosopher, Krishnites, we do not think in that terms. Suppose in next life I become some demigod like Lord Brahmā or the Moon or the Sun. They are all demigods. Or Vāyu, Varuṇa. The Vaiṣṇava says, "No, we don't want this." Because either you become Rockefeller or Ford in this life, and next life the king of moon planet or sun planet or in any way, up to the Brahmā planet, Brahmaloka, Lord Brahmā, Kṛṣṇa says, ābrahma-bhuvanāl lokāḥ punar āvartino 'rjuna (BG 8.16): "My dear Arjuna, by your endeavor, even you become promoted to the highest position of this material world, still, you have to die, and again—either come down or remain there—there will be change of body." Ābrahma-bhuvanāl lokāḥ punar āvartino 'rjuna (BG 8.16). "So why should you be implicated in these material activities? Try to come to Me, back to home, back to Godhead. Then you'll haven't got to return again in this material world. That is the highest perfection." So this is called brahma-jijñāsā. By inquiring about Brahman one can understand that "Even if I go to the topmost planet of this material world, the four principles of miseries—birth, death, old age and disease—there is."