(Prabhupada's lecture - Śrīmad-Bhāgavatam 2.1.4 – Delhi, November 7, 1973)
This whole material world is based on sex desire. Puṁsaḥ striyā mithunī-bhāvam etam [SB 5.5.8]. Everywhere, either in cat society, dog society, human society, bird society, beast society, anywhere you go, even aquatics, fish, insects, flies, ants—everywhere you will find this attraction, sex attraction. This is the ādi-rasa. Everyone is trying to get some taste. So this is the beginning of taste. So we have got attraction, natural attraction. Puṁsaḥ striyā mithunī-bhāvam. This material world is simply attraction of this sex life. So when they are actually unite(d) in different ways... But they must unite. Either in a legal way or illegal way, they must unite. Because attraction is there. But human civilization, they have given some law, not like cats and dogs. Just like in the morning, in the street we saw, the dogs were enjoying sex life. So in the human society, that kind of sex enjoyment, although it is now actually being done in the Western countries... I have seen it. You see? In some public parks or in beach. They don't care, becoming just like cats and dogs, no human civilization. So for human civilization, there is some restriction: the allowance, marriage. That is a civilized way. And the fact is the same, but in a civilized way there is.
But civilized or uncivilized, as soon as there is sex life, then the attraction for material world immediately increase hundred times. When one remains single, the attraction is not so strong, but when they unite, the attraction becomes very strong, because to maintain a wife, you require room, apartment, gṛha, which is called gṛha. So therefore they are called gṛhastha, "one who lives in a gṛha, in a house." Everyone lives in a house. We are also living in a house, this temple. But gṛhastha means to living with wife in the house. Na gṛhaṁ gṛham ity āhur gṛhiṇī gṛham ucyate. Simply gṛhastha does not mean to live in a room or in a house, but to live with a wife. Gṛhiṇī. So then we require apartment or room or house, according to our position. Then we require some land for producing food. Now they don't require land for producing. They require something else—some slavery or some work in the factory. But formerly, everyone used to have a, possess a piece of land for producing food. Kṣetra. Gṛha-kṣetra. Then, when there is marriage, there will be children, suta. Then there will be friends also, relatives, suta āpta. Gṛha-kṣetra-sutāpta. Then vitta, the central point money. So as soon as they are united, immediately these things will be required. Gṛha-kṣetra-sutāpta-vitta. In this way the attachment for this material world increases.