Kṛṣṇa therefore says in the Bhagavad-gītā, mattaḥ parataraṁ nānyat kiñcid asti dhanañjaya (BG 7.7). Absolute Truth means the Supreme. In the Brahmā-sūtra it is indicated that the human form of life is meant for understanding the Absolute Truth. Athāto brahma jijñāsā. We have to enquire about the Absolute Truth. That is human form of life, not to waste our time simply going to the market and enquire, "What is the rate of rice and what is the rate of ḍāl?" That should go on, but along with it, there should be inquiry what is the Absolute Truth, what is Kṛṣṇa, what is God. That is beginning of human form of life.
Therefore in the Śrīmad-Bhāgavatam it is said, parābhavas tāvad abodha-jāto yāvan na jijñāsata ātma-tattvam (SB 5.5.5). The foolish persons, foolish living entities, abodha-jāto . . . All of us, we are born ignorant; otherwise why we are sent to school? Why the children are sent to school? Because they're abodha-jāto. By birth they are all śūdras, abodha. Therefore according to Vedic system there are saṁskāras, reformatory methods, and when the child is taken for saṁskāra, that is called upanāyana. Upanāya means bringing him nearer to understand spiritual life. That is sacred thread ceremony.