So there is no question of happy life within this material world. This is to be understood first. Very pessimistic. Those who are intelligent, they are very pessimistic. Even materially they are pessimistic. They are living some standard of life, "This is not good." There are many houses, very low, and cottage, so people think that "This is not very good life. Let us have very nice building." So this struggle is going on. That is human nature, that unless. . . Until he approaches the final post or platform of happiness, he is not happy. That is called struggle for existence and survival of the fittest. So sura-asura(?) means those who are trying to reach the ultimate goal of life where happiness is guaranteed. One who is trying for that, he is called sura, devatā. And one who is satisfied with this temporary so-called happiness, he is called asura. That is the difference.
Now, if you want to reach to the ultimate goal of life, where only blissful life, sac-cid-ānanda-vigrahaḥ (Bs. 5.1), eternal body of knowledge and bliss, then you have to become sura. It is not that the asuras will remain asura. It doesn't matter. Even born in the asura family one can become sura. Just like Prahlāda Mahārāja. His father was asura, but he was perfect sura. That is possible. It is not prohibited to anyone. If he wants to become sura. . . Just like in ordinary life also: If you are determined to become medical man, you can become. There is no impediment. If you are persistent, you can become medical man, engineer or anything. People are trying, education. Similarly, if you want to become sura, there is no impediment, there is no obstacle. You can become. Simply you have to know what sort of life we should accept, pravṛtti—this is called pravṛtti—and what sort of life we should reject. This is required. This is the distinction between sura and asura.
Just like these European, American boys, before coming to my shelter, they were doing everything. We prohibit illicit sex. We prohibit intoxication. We prohibit meat-eating. We prohibit gambling. So these boys and girls were accustomed to all these habits, pravṛtti. But they have now changed their pravṛtti because they want to become sura. They want to achieve the ultimate goal of life. One may not know what mode of life we should accept. One may not know what mode of life we should reject. But in the śāstra, in the teachings of great men, learned scholars, things are there. We have to accept. We may not know, but we should accept. The Kṛṣṇa consciousness movement is for this purpose, to change the pravṛtti, nivṛtti. Just like there is pravṛtti for meat-eating. We are advising, "Please do not eat meat." This is nivṛtti. Before that, they do not know what is the difference between meat-eating and not meat-eating. But now they are understanding. Therefore they are becoming sura.