Prabhupāda: So, first-class man is described, śamo damaḥ tapaḥ śaucaṁ kṣāntir ārjavam, these are the qualifications, second-class these are the qualifications, third-class, fourth-class. So there are different varieties of men, so divide them according to the instruction of Bhagavad-gītā, then whole human society will be... There are four division of your body—the head division, the arm division, the belly division, the
leg division. If you engage the head for walking, that is mistake, and if you engage the
leg for thinking, that is mistake. Similarly, there are different types of men, combine together, and it will be nice body, the
leg will walk, the hand will protect, the head will give instruction, and the belly will get energy by eating food. Those divisions are required. Not that everyone is all. No, there must be division of labor. So that is described, how to make civilization perfect, who is going to hear and take it. Cātur varṇyaṁ mayā sṛṣṭaṁ guṇa-karma-vibhāgaśaḥ (
BG 4.13). If you can adjust things, you can utilize things, then everything will be useful. And if you do not know how to utilize things, then everything will be useless. Take instruction from Bhagavad-gītā and make everything useful. Then the human society will be perfect. Otherwise you'll go on manufacturing ideas, you'll never be successful. Because nature's law is working, you cannot interfere with the nature's law. That is not possible. You may think yourself very much advanced in science, but nature's law, you cannot interfere. Just like now there is movement, man and woman, equal.