If you have to produce a child, you have to sow. The man has to sow the seed in the womb of the woman. This is a practical.
So the seed is eternal. That we get information from Vedic literatures. Bījo 'haṁ sarva-bhūtānāṁ (Bg 7.10). Na hanyate hanyamāne śarīre (BG 2.20). That bīja, that seed, does not, I mean to say, annihilate because the body is annihilated. This is the basic principle of understanding for making progress in spiritual life. One who does not understand this basic principle, that the spirit soul, the seed, is eternal, and it is transmigrating different bodies... And factually we know that "My father gave the seed in the womb of my mother, that seed. And from that seed developed this body. But I am... When my body was just like, as small, just like a pea, I was there. And I have become so big. I am there. So many bodily changes have taken place, but I am there." Similarly, tathā dehāntara-prāptir dhīras tatra na muhyati (BG 2.13). Similarly, when we change this body finally and take another body, so one who knows the fact or the science of birth and death, he is not disturbed. He is not disturbed. Dhīras tatra na muhyati. Dhīra means intelligent, cool-headed, not rascal. So this very word is used, dhīra. Dhīra means cool-headed, not disturbed. Na muhyati: "He is not bewildered." He's just changing this body. So now the business is that before changing this body, "What kind of other body I am going to get?" That is my business. That we can get according to as I deserve. Just like as you educate yourself in your childhood, so you get a particular type of post when you are businessman or working man. If you have got sufficient education, you could get good post, good salary. And if you are a nonsense, then you have to work like ordinary man, no good post. Just we have got, we get different types of post according to our culture or education, similarly this body, this human body, is the preparation ground for the next type of body. If you neglect that, then we are getting..., we are taking the risk.