We should cooperate, but there must be these four classes of men. Not that simply śūdras and vaiśyas. At the present moment, there are few vaiśyas and mostly śūdras. Rajas-tamo-bhāvāḥ (SB 1.2.19). Rajas-tamaḥ, by the rajo-guṇa, the kṣatriya are produced, and by tamo-guṇa the vaiśyas are produced, and vaiśyas are mixed up, rajo-guṇa and tamo-guṇa. So it doesn't matter in whatever guṇa or status of life we are. If all of us take to Kṛṣṇa consciousness, then our life is successful, mutual cooperation. Therefore Kṛṣṇa says, manuṣyāṇāṁ sahasreṣu kaścid yatati siddhaye (BG 7.3).
Now, how to make perfect, perfection of life, siddhi? That is stated in the Caitanya-caritāmṛta:
- anādi-bahirmukha jīva kṛṣṇa bhuli' gelā
- ataeva kṛṣṇa veda-purāṇa kailā
- (CC Madhya 20.117)
Because we have all forgotten Kṛṣṇa. That is our miserable condition of life. We are all forgotten about Kṛṣṇa. Therefore Kṛṣṇa is teaching us personally. Five thousand years ago, He personally appeared and teaching us, we forgetful of Kṛṣṇa, the whole human society. Kṛṣṇa is teaching everyone. Don't think that Kṛṣṇa is teaching only in India, and to the brāhmins or the Hindus.
Kṛṣṇa is for everyone. Therefore Kṛṣṇa is being accepted by everyone all over the world. It is our duty. Caitanya Mahāprabhu therefore says it is the duty of all Indians to spread this Kṛṣṇa consciousness movement for para-upakāra, all over the world. That is our business.