By knowing one thing, everything becomes known

Brahmavidyā paramparā was established from the last mantra. Now, we have the teacher Angiras, who has this knowledge and available to teach. Śaunaka approached Angiras and got the knowledge from him. The dialogue between Angiras and Śaunaka begins the teaching of the Upaniṣad.

śaunako ha vai mahāśālo'ṅgirasam vidhivadupasannaḥ papraccha |

kasminnu bhagavo vijñāte sarvamidam vijñātaṃ bhavatīti ||1.1.3||

Śaunaka, the famous householder, approached Angiras as per the stipulation and asked thus: O revered sir! By knowing which one thing alone, does everything become known?

śaunako ha vai mahāśālaḥ - Śaunaka was indeed a great householder. The word mahāśālaḥ literally means the one who has big halls, including yajña-śālā (the hall used for performing fire rituals) and pāka-śālā (the kitchen). Food distribution is one of the limbs in the performance of rituals. Thus, mahāśālaḥ indicates that Śaunaka had done lot of rituals and lived a life of prayer and dharma, thereby has gained purity of mind. Mahāśālaḥ also indicates that he was a famous gṛhastha (married person), where householder life is a training ground for one to gain maturity in living one’s life.

Since the qualification for self-knowledge is there, therefore aṅgirasam vidhivadupasannaḥ papraccha - he approached Angiras (for the self knowledge) according to the stipulated method. He knew how to approach a teacher as per rule. Later, in this section, it is stated that a student should approach a teacher as a samitpāṇi, with a small bundle of twigs, used for daily rituals, in his hands. The twigs represent the student’s readiness to be of service.

Having approached Angiras in this manner, Śaunaka asked a question, kasminnu bhagavo vijñāte sarvamidam vijñātaṃ bhavatīti - oh revered sir, by knowing which one thing alone does everything become known? A contention is raised about Śaunaka’s question: how does he know that there is such thing, by knowing which one thing, everything is as well known? We do not see such a thing in the world. We always find that by knowing one thing, only that thing is known, and it is also not known completely. The first answer is that Śaunaka is a mahāśāla, indicating that he might have heard sentences like the ones in Chāndogya upaniṣad when Śvetaketu returns home after studying the Veda, and his father Uddālaka asks him whether he has learned that teaching: “by knowing which, the unheard becomes heard, the unthought becomes thought, and the unknown becomes known.” Śvetaketu asks how such knowledge is possible. Uddālaka then gives the famous examples: “just as, by knowing one lump of clay, everything made of clay is known.”

And Śaunaka also sees such a phenomenon in the world that, by knowing the truth of one gold ornaments, everything else made of gold is as well known. By knowing the material cause, all its products are as well known. So too, there must be one material cause for the entire universe, and  knowing that cause, everything else becomes as well known. If the two things (the cause and effect) discussed above are separate, then by knowing one, we are not going to know the other.

It doesn’t mean that one who knows the truth of the world will know every single specific thing in the world. Since the truth of everything is only one cause, the second thing is as good as not there. What you count as second, is only name, forms, and function. Just like the bangles, necklaces, rings, etc. are nothing but gold alone. Effects are just names and forms which don’t have the reality of their own. By knowing that vastu, this jagat is as well known; then the jagat should not be different from that vastu. From the question, we understand that this is the only way to answer it. Everything that is here has to be that very vastu and not separate from it. But the vastu has nothing to do with any of them. The vastu remains in its original form in spite of appearing as this jagat. The relationship between the vastu brahman and the world is a satyam-mithyā relationship.

The ability of inquiry on the part of Śaunaka is also shown here.