Gatisāmānyāt  गतिसामान्यात् (I.i.10)

Gati – state, cause; sāmānyā – same;

Because the state of knowledge is the same, as explained in upanishad-s, or upanishad-s say that cause is the same for existence, etc, there is no second to Brahman. This Brahma Sutra reaffirms the omnipresent and omnipotent nature of Brahman. Since there is no second in hierarchy, Brahman is omnipresent and omnipotent. Many of the aphorisms convey that Brahman alone is the cause and not pradhāna, as described in Sāṁkhya philosophy. According to Sāṁkhya, the universe has originated from pradhānaka, the original germ out of which the material universe has evolved. This point of argument is refuted in the first few sūtra-s, by saying that the universe has not originated from pradhānaka, but from Brahman. To prove this argument, Brahma Sūtra has quoted several examples from the point of view of Vedānta (essence of Vedas, upanishad-s). Even if there is a subtlest teaching somewhere in some upanishad, the point of view of Sāṁkhya philosophy can further be discussed. But, none of the upanishad-s make any reference, whatsoever towards pradhānaka of Sāṁkhya. Hence, the argument that there is some other thing or things that is responsible for the origin of the universe is totally negated through these aphorisms. This is done mainly to avoid any confusion in the minds of students, who eagerly pursue spiritual knowledge. In spiritual pursuit, faith is paramount, as spiritual knowledge deals only with subtleties.

This Brahma Sutra says, since the same knowledge is imparted in all the upanishad-s, obviously, the universe is not only created from Brahman, but also sustained and annihilated by Him. Taittirīya upanishad (II.i.1) explains Brahman. It says, “Brahman is Truth, Knowledge and Infinity (satyaṁ-jñānam-anantaṁ brahma). He, who realizes the Self through his intellect not only realizes Brahman, but also attains everything he wants (Such a realized person will never desire for any material things is to be understood). From this Self comes space, air, fire, water, earth, etc in an orderly manner.” All other upanishad-s endorse this revelation. For example, Chāndogya upanishad (VII.26.1) says, “everything comes from the Self.” Similarly, Praśna upanishad (III.3) says, “prāṇa comes from the Self. Like a body having its shadow (shadow follows the body everywhere), prāṇa is inherent in Brahman (like a shadow being inherent in a body); and It assumes a particular shape or form, when it so wishes.” There are many such elucidations in every upanishad. When upanishad-s which are considered as the source of revelation of the highest knowledge about the Self, how there can be an alternative to Brahman? Thus, with authority and authenticity, Brahma Sūtra-s rule out any remote chances of any possible substitute to Brahman.

Śrutatvācca श्रुतत्वाच्च (I.i.11)

Śrutatva – taught; aca (derived from añc) – making clear.

Brahman alone is Supreme is the teaching, which is made abundantly clear in all upanishad-s. Śruti means Vedas; upanishad-s, classified as Smṛti-s, convey the essence of Vedas to realize Brahman.
Vedas can be interpreted in two ways; one is the gross interpretation which leads to various yajña-s (sacrifices in fire rituals as oblations), and another is subtle interpretation, which leads to the revelations of upanishad-s and Brahma Sūtra.

Śvetāśvatara upanishad (VI.9 and 10) explains Brahman in a different way. “There is nobody who can govern Him; there is nothing by which He can be identified; He is the cause of all. Like a spider hides itself in its web, Brahman hides Himself by the projections of His māyā such as shapes and forms and by actions.” This goes to prove again the omnipotence of Brahman. All that we see are the projections of Brahman, as we see only the exterior and not the interior. Only in a space within the body, Brahman is present. Though Brahman is present all through the body, in order to help us in realizing Him within, a certain place is fixed such as a cave within the heart or in the pineal gland.

Having thus established the Supremacy of Brahman, now Brahma Sūtra proceeds to explain Brahman without attributes ((Nirguṇa Brahman) and Brahman with attributes (saguṇa Brahman) from the next aphorism onwards.

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