According to followers of the Vedic principle, their process is śruti-pramāṇam. Śruti-pramāṇam means if it is mentioned in the Vedas, Upaniṣad, then it is pramāṇam. Śruti-pramāṇam.
Lecture on SB 1.5.35 -- Vrndavana, August 16, 1974:
So bhagavat-toṣaṇam, we must know first of all who is God, who is Bhagavān. So śāstra says, authority says, and history says. What more proof you want? Huh? What more proof? Is there anyone to challenge Kṛṣṇa? Everything is there. Still, why you are searching after God? This is foolishness. This is foolishness. Owls', owls' philosophy. Owls' philosophy... The owl will not open the eyes to see the sun. Just open your eyes, you see, here is sun. "No, there is no sun." This is owls' philosophy. Close the eyes, meditate. And the God is here, "No, I'll not open my eyes."
So we do not follow this philosophy, owls' philosophy. We follow real philosophy. What is that real philosophy? Śruti-pramāṇam, evidence from the Vedas, history, aitihya-pramāṇa, history. And anumāna-pramāṇa. There are many, pratyakṣa, anumāna, aitihya... So out of that, there are so many evidential processes, but according to followers of the Vedic principle, their process is śruti-pramāṇam. Śruti-pramāṇam means if it is mentioned in the Vedas, Upaniṣad, then it is pramāṇam. Śruti-pramāṇam. So Vedas, there are four Vedas and 108 Upaniṣads, and then eighteen Purāṇas, then this Mahābhārata. So all these are Vedic literatures. Śrīmad Madhvācārya describes them, these are Vedic literatures. Not only the four Vedas—Sāma, Yajur, Ṛg, Atharva—but expansion of Vedas. Purāṇas, they are also Vedas. So in the Purāṇa, in the history, in the Vedas, by the authorities.
Just like Brahmā, the best authority because he is the first living being created within the universe. Ādi-puruṣa. Not ādi-puruṣa; ādi-kavi. Ādi-puruṣa is Kṛṣṇa. Brahmā is ādi-kavi, the original learned scholar. So our theory of creation means first of all Brahmā is created. So Brahmā is called ādi-kavi. Tene brahma hṛdā ya ādi-kavaye (SB 1.1.1). Ādi-kavaye means Brahmā. So Brahmā's knowledge, what does he say? Brahmā says govindam ādi-puruṣaṁ tam ahaṁ bhajāmi **. Brahmā says Govinda, Kṛṣṇa. Cintāmaṇi-prakara-sadmasu kalpa-vṛkṣa-lakṣāvṛteṣu surabhīr abhipālayantam (Bs. 5.29). He's giving description about Kṛṣṇa in the Brahma-saṁhitā. And the description of Kṛṣṇa's abode. Cintāmaṇi-prakara-sadmasu kalpa-vṛkṣa-lakṣāvṛteṣu surabhīr abhipālayantam (Bs. 5.29). Everything is there. This is authority, śruti. Kṛṣṇa is very much fond of tending cows. Surabhīr abhipālayantam. Cintāmaṇi-prakara-sadmasu. He has got His abode, Goloka Vṛndāvana, where the residential houses are made of cintāmaṇi, touchstone. Touchstone, we have heard the description. Touchstone means the stone which you touch to the iron and the iron becomes gold. So such touchstone, they're used as brick. Cintāmaṇi-prakara-sadmasu kalpa-vṛkṣa-lakṣāvṛteṣu (Bs. 5.29).
And kalpa-vṛkṣa. This is Kṛṣṇa's abode. They are not like this. They are all spiritual. Here it is, everything is material, but there is spiritual touch. That spiritual touch we are describing in the Bhagavad-gītā, bījo 'haṁ sarva-bhūtānām (Bg 7.10). Without spiritual touch, there is no question of material manifestation. That is not possible. This body, your body, my body, this is material—everyone knows. It is made of earth, air, water, fire, like that. But how it is manifested? How the beautiful body is manifested? Because there is spiritual touch. The spirit soul is there. Dehino 'smin yathā dehe kaumāraṁ yauvanaṁ jarā tathā... (BG 2.13). This external body is changing, but it is forming on account of that spiritual touch. That spiritual touch means Kṛṣṇa. Bījo 'haṁ sarva-bhūtānām. So therefore the origin of everything is Kṛṣṇa. Just like the origin of a big tree is the root. Similarly, Kṛṣṇa is the ādi-puruṣam. Govindam ādi-puruṣam, sarva-kāraṇa-kāraṇam (Bs. 5.1). Just like in the tree there are trunk, branches, twigs, sub-branches, leaves, flowers, so many things. But the cause is the root.