The human life is meant for composing an association where devotees may take part, sādhu-saṅga. In the Śrīmad-Bhāgavatam it is said, mahat-sevāṁ dvāram āhur vimuktes (SB 5.5.2). Mahat-seva. Mahat means whose mind has been broadened, not crippled. Cripple-minded man thinks in terms of personal interest or society's interest or community's interest, nation's interest or international interest.
Even international interest is cripple-minded, because there are many planets. If we expand ourself from self-interest to family interest, from family interest to community interest, similarly, even you expand to the international interest, it is imperfect unless your interest is expanded up to the Supreme Personality of Godhead.
That is the Vedic injunction in the Ṛg Veda, oṁ tad viṣṇoḥ paramaṁ padaṁ sadā paśyanti sūrayaḥ (Ṛg Veda 1.22.20). Those who are advanced in knowledge, their aim is, their interest is, the Supreme Personality of Godhead, Lord Viṣṇu. Tad viṣṇoḥ paramaṁ padam. But people do not know what is his self-interest. That is indicated in the Śrīmad-Bhāgavatam, na te viduḥ svārtha-gatiṁ hi viṣṇu (SB 7.5.31).
Everyone should be self-interested. But in this material world, being illusioned, being bewildered by the material energy, we are thinking our self-interest in terms of our particular type of education. Somebody is thinking that, "Simply I have to maintain my body somehow or other." Little expanded, thinking interest of society, you go on. But they do not know that the self-interest must expand to Lord Viṣṇu. And that is explained by Prahlāda Mahārāja.