Srila Prabhupada's lecture - Śrīmad-Bhāgavatam 1.1.2 - London, August 15, 1971
So this is the actual human life, not that simply imitating the animals: how to eat, how to sleep, how to sex. No. Śāstra says that is already established. Don't worry. Just like the swans and the ducks in St. James. They don't worry, "Oh, what to eat?" But they're getting their eatables. They don't go to office, to factory. Even the swans and ducks, and what to speak of human being? This is nature's study, that the swans and ducks, they are getting at home, they are getting their sex life. Immediately, everything is there. According to their standard, everything is there. Āhāra-nidrā-bhaya, these are the four things required for this body. But even a small duck and swan, he has got everything ready there in St. James Park. He does not go to the Downing Street. So why don't you study?
So if a swan is provided with all the necessities of life, why I shall not be? I am so much developed human being. Why I am so much busy in economic development? This is called illusion. But one who is advanced in knowledge, he knows that "If the swan is already provided with all the necessities of life, then I shall also be provided with all the necessities of life. There is no need of endeavoring for it." That is a fact. That is the fact.
Jaya Srila Prabhupada !