Tyaktvā dehaṁ punar janma naiti BG 4.9. But people are so attracted to this material body that they are prepared to become cats and dogs next life, but they are not prepared to go back to home, back to Godhead. This is the problem. So why this problem? Because the human society is in chaos. A chaotic condition. There must be division of four classes. One class must be brāhmaṇa, intelligent class of men. And one should be kṣatriya, one class, the administrators. Because human society, they require good consulting brain, good administrators, good producers and good worker. That is the division of brāhmaṇa, kṣatriya, vaiśya, śūdra. Therefore Kṛṣṇa says: catur varṇyaṁ mayā sṛṣṭam BG 4.13. In order to keep smooth facilities for human life, there must be four divisions. If you say that don't, "We don't require brāhmaṇa." If you don't require brāhmaṇa, then you'll suffer.
Just like you have got this body. And if you think "This part of the body's very expensive, always eating. Cut it off." Then you'll dead. Similarly, just to keep your body in good condition, in living condition, you must have your head, you must have your arms, you must have your belly, you must have your legs. You cannot say that "I can avoid this part of the body." No. Similarly, catur varṇyaṁ mayā sṛṣṭam BG 4.13, the four divisions of the society must be there. Otherwise it will be chaotic or dead body.
So at the present moment, the difficulty is there is no brāhmaṇa, there is no kṣatriya. There are only the vaiśyas and the śūdras, belly, vaiśya means belly and śūdra means the leg. So if, out of the four divisions, one is wanting, the society must be in chaotic condition. The four must exist. Although comparatively head is the most important part of the body, still you cannot neglect the leg also. This is a cooperative combination.
So we have to cooperate. It doesn't matter. One is very intelligent. One is less intelligent. One is less intelligent. The four classes are there. The most intelligent class is the head, brain. And the next intelligent class, the administrator, government. The next intelligent class, the industrialists, merchants. The next intelligent class is the worker. All of them are required. But at the present moment, there is only this mercantile industrialist and worker. There is no brain. How to conduct society? How to become perfect human society, how to fulfill the mission of human society, for these things, there is no brain.