So we believe. We blindly believe, blindly or knowingly. It is not possible knowingly, but if we accept Kṛṣṇa's argument, then we have to believe. Kṛṣṇa does not say anything without any reason. Nobody says. No authority says like that. So what to speak of Kṛṣṇa? Kṛṣṇa is the greatest authority. If we blindly accept His statement, that is also good, and if we apply our reason and argument, that also you can do. Kṛṣṇa says in the Bhagavad-gītā,
- dehino 'smin yathā dehe
- kaumāraṁ yauvanaṁ jarā
- tathā dehāntara-prāptir
- dhīras tatra na muhyati
- (BG 2.13)
He is giving very practical example that because the soul is within this body, therefore bodily changes are taking place. Now, suppose if a child is born dead. That... You can keep it by some method, preservative method, but it will not grow. One can understand very easily. Because the soul is there, therefore the child from the womb of his mother grows gradually. Grows means changing body. Everything, information, is there in the Śrīmad-Bhāgavatam. The man and woman, father and mother, after sex the two secretion is emulsified and it takes a form like a pea. And the small living entity, the measurement is also given. Keśāgra-śata-bhāgasya śatadhā kalpitaḥ: (CC Madhya 19.140) "One ten-thousandth part of the upper portion point of hair." You know the point of hair. Now divided into ten thousand part and take one part. That is the form of the soul. That little spark takes shelter into that emulsified pea, and because the soul is there within, it develops from the mother's womb.