The material nature is divided into three modes: sattva-guṇa, tamo-guṇa, rajo-guṇa. So to become within the material nature, under the control of the material nature, means to accept one of these guṇas, sattva-guṇa, rajo-guṇa, tamo-guṇa. So if you accept this sattva-guṇa, the brahminical qualification, satyaṁ śamo damas titikṣā ārjavaṁ kṣāntiḥ, jñānaṁ vijñānam āstikyaṁ brahma-karma svabhāva-jam... (BG 18.42). If you associate with the brahminical qualifications, then you get nicer body. Ūrdhvaṁ gacchanti sattva-sthāḥ (BG 14.18). Those who are associating with the sad-guṇa, they are also described. Sad-guṇa means satyaṁ śamo damas titikṣā ārjavaṁ kṣāntiḥ, jñānaṁ vijñānam āstikyaṁ brahma-karma... This is brahma-karma. So tapasya means come to the brahma-karma, not to the śūdra-karma. Kāraṇaṁ guṇa-saṅgo 'sya (BG 13.22). Don't associate with the śūdra qualifications. Now, what is the śūdra qualification? Paricaryātmakaṁ kāryaṁ śūdra-karma svabhāva-jam (BG 18.44). You are highly educated, but your desire is how to get a service. Paricarya... I am highly educated, but unless I render service to somebody else like a dog, I am not recognized. This is called śūdra-karma. Why a brāhmaṇa, kṣatriya, vaiśya should search after service? Therefore in this Kali-yuga it is said, kalau śūdraḥ sambhavaḥ: "Kalau, in this Kali-yuga, everyone is almost śūdras." There is lack of brāhmaṇa. There is lack of kṣatriya and vaiśya.
So in Bhagavad-gītā we'll find all the solutions of the human problems, all the solutions. Cātur-varṇyaṁ mayā sṛṣṭaṁ guṇa-karma-vibhāgaśaḥ (BG 4.13). Unless you divide the whole human society into four divisions, the brāhmaṇa, kṣatriya, vaiśya and śūdra... You must have to divide. You cannot say "classless society." That is useless society. Classless society means useless society. There must be an intelligent high class, ideal class of men to see the "Here is human civilization." That is brāhmaṇa. Cātur-varṇyaṁ mayā sṛṣṭaṁ guṇa-karma... (BG 4.13). Unless people see the ideal men, how they will follow? Yad yad ācarati śreṣṭhaḥ, lokas tad anuvartate (BG 3.21). The brāhmaṇa is compared with the brain of the body. Unless there is brain, what is the use of these hands and legs? If one's brain is cracked, madman, he cannot do anything. So at the present moment, because there is scarcity of brahminical qualified men in the whole human society... It is not meant... Brāhmaṇa is not meant for simply for India of Hindus. For the whole human society. Kṛṣṇa never says that the cātur-varṇyaṁ mayā sṛṣṭam (BG 4.13) is meant for India, or for Hindus, or for a class of men. For whole human society, there must be a very ideal intellectual man, so that people will follow. Brain, brain of the society. That is the teachings of Bhagavad-gītā. You cannot say that "We can do without brain." Suppose from your body if the brain is cut off, your head is cut off, then you are finished. What the hands and legs will do if there is brain, if there is no brain? So at the present moment there is scarcity of brain in the whole human society. Therefore, it is in the chaotic condition. So there is need, as it is stated in the Bhagavad-gītā. The human society, the whole human civilization, must be reformed in this way, that there are intellectual class of men, naturally. There are first-class intellectual class of men, second-class intellectual, third-class, fourth-class, like that. So the first-class intellectual man, they must be brāhmaṇas, in the brahminical qualification, and they must be Kṛṣṇa conscious. Then they can guide the whole society in the right way, and there will be no problem. This is Kṛṣṇa consciousness movement.
So here Kṛṣṇa says how to become Kṛṣṇa conscious. That is for the brāhmaṇas, or the intellectual class of men. That is being described by Kṛṣṇa. What is that? Mayy āsakta-manāḥ: "The mind should be attached upon Me, Kṛṣṇa." This is the beginning. Some way or other we have to... Our mind is attached to something else. Mind cannot be detached. We have got so many desires. So mind's business—to become attached. Therefore, I accept something, I reject something. This is mind's business. So you cannot become zero, you cannot become desireless. That is not possible. Our process... Just like others, they say, "You become desireless." That is a foolish proposal. Who can become desireless? It is not possible. If I am desireless, then I am a dead man. A dead man has no desire. So that is not possible. We have to purify the desires. That is required. Purify the desires. Sarvopādhi-vinirmuktaṁ tat-paratvena nirmalam (CC Madhya 19.170). This is called purification. Nirmalam. Tat-paratvena. Tat-paratvena means when God conscious, Kṛṣṇa conscious, then desires become purified.