Till now 171 aphorisms have been discussed out of 555 aphorisms of Brahma Sūtra. In the previous sūtra-s (1 to 171), Brahman as the cause of the universe has been established. In this section containing 45 sūtra-s other philosophies such as Sāṁkhya, Vaiśeṣika, Buddhist doctrine, Jaina doctrine, Pāśupata doctrine and Pāñcarātra (Pancharatra) doctrine.

First ten sūtra-s again refute Sāṁkhya philosophy, as most of the aphorism in the previous section refuted Sāṁkhya philosophy from different angles. But the refutation in this part is purely based on reasoning.

Brahma Sutras II.ii.1

Pradhāna, which is explained as the cause of the universe cannot be accepted, as there is no sequential method to explain creation as in Advaita philosophy, which is based on the revelations of Upaniṣad-s. Sāṁkhya philosophy says that a pot which is made of clay is part of the earth. Thus a pot that is made out of clay taken out from the earth forms a part of earth or transfused with the earth. Similarly, the three guṇas – sattva, rajas and tamas originate only from Pradhāna cause creation.
But this argument is refuted by Vedāntin-s on the following grounds. Pradhāna has no intelligence (Brahman is full of knowledge) and without jñāna (knowledge) creation cannot proceed smoothly. For example, clay on its own cannot form a pot and it needs the assistance from the potter. Further effects of guṇa-s are restricted only to the individual beings and not connected to macrocosm. Thus Pradhāna cannot be the cause of the universe, whereas Brahman is.

Brahma Sutras II.ii.2

Pradhāna has no tendency to create because it has no jñāna (knowledge), where Brahman has the will to create (icchāśakti). In the absence of will to create, creation cannot happen and if the will and the knowledge to create is there, creation happens in an orderly manner. Brahman is omniscient whereas Pradhāna is not. Hence Pradhāna cannot be the creator.

Brahma Sutras II.ii.3

Sāṁkhya argues that it is only due to Pradhāna milk is produced which nourishes not only the calves but also all other beings. Similarly, water is also produced by the earth to nourish both good and bad beings. Thus Pradhāna acts impartially for the benefits of all the beings. Then why not Pradhāna be the creator? This argument cannot be accepted because Bṛhadāraṇyaka Upaniṣad (III.vii.4) says, “He (Brahman) inhabits water, but is within it, whom water does not know, whose body is water and who controls water from within is the Self.” According to this Upaniṣad, it is not enough to merely cause something. In order to be the Self it has not only to create, but also permeate the created and hold control of the creation by remaining within. As this capacity is not there for Pradhāna, it cannot be creator.

Brahma Sutras II.ii.4

In Pradhāna all the three guṇas exist in equilibrium (avyakta - Lalitā Sahasranāma 398). Apart from equipoise of guṇa-s, nothing exists in Pradhāna (Prakṛti), through which it can create, sustain, dissolve, etc. Thus Pradhāna becomes helpless. But Brahman has His own Power acting as māyā, through which He perfectly executes all His acts.

Brahma Sutras II.ii.5

Sāṁkhya argues that grass consumed by a cow becomes milk and similarly Pradhāna can transform into mahat. Mahat is the second principle from prakṛti as per Sāṃkhya philosophy. Mahat means great. This is not accepted as Pradhāna cannot change into milk straight from the grass, as the grass is to be first consumed by a cow. Thus the change is not spontaneous, but gradual, over a period of time and is subjected to conditions. For example, if a bull grazes on grass, it does not give milk. This is happening only because of the will of Brahman (icchāśakti). Hence, the role of Pradhāna cannot be accepted as the creator.

Brahma Sutras II.ii.6

Even for the sake of argument, if Pradhāna as the creator, what is its purpose of being a creator? Pradhāna cannot cause bliss and liberation. If Pradhāna cannot offer liberation, how can it be the creator?

Brahma Sutras II.ii.7

Sāṃkhya says that Puruṣa (Soul) cannot direct the movements of Pradhāna, as Soul is only a witness and does not cause any actions. But Sāṃkhya says, it is like magnet controlling iron, both being insentient. This argument also is not accepted because Sāṃkhya says that Pradhāna is independent. Further, Puruṣa itself being inactive how can one insentient lead another insentient Pradhāna? On the contrary, Brahman acts through māyā and thereby He always remains unchanged. Brahman does not undergo changes or modifications.
If we go by Sāṃkhya philosophy, assuming that all other activities are acceptable, there is no liberation for the souls. When there is no liberation for the souls, purpose of philosophy is not served. Even on this basis, Sāṃkhya doctrine is not accepted.

Brahma Sutras II.ii.8

According to Sāṃkhya philosophy, Pradhāna is inactive because all the three guṇas are in equilibrium. Activity cannot happen unless this equilibrium is modified. Creation has to progress from the avyakta stage by modifications and changes. How modifications can happen without external agencies? Puruṣa cannot cause modifications, as an individual soul is not concerned about these modifications, as soul is always a witness. Hence, Pradhāna cannot be considered as the creator.

Brahma Sutras II.ii.9

As discussed earlier, Pradhāna has no wisdom (jñānaśakti) and therefore cannot create. Guṇa-s have some inherent powers in them and they can by themselves make modifications, which could lead to further creation. As Pradhāna is devoid of intelligence, proper process of creation cannot be executed by it. Further, equilibrium of guṇa-s cannot be modified without an external influence, as Pradhāna itself is inert. But on the contrary, Brahman has the will to create using His intelligence and that is why He says, “Let me create the universe…”

Brahma Sutras II.ii.10

Thus, Brahma Sūtra demolishes Sāṃkhya philosophy by pointing out its inconsistency. First, it does not follow the guidelines laid down by Vedas. Secondly, it has numerous loose ends. For example, five tanmātra-s (rudimentary subtle elements such as sound, touch, etc) originate from mahat and sometimes from ego. Similarly there are contradictions about antaḥkaraṇa. Sometimes it says that antaḥkaraṇa is a single entity and other times, it is explained as the combination of mind, intellect and ego. Thus there are several contradictions. Not only on the basis impracticality, but also on the basis of several contradictions, Sāṃkhya philosophy is set aside.

The next seven aphorisms argues on Vaiśeṣika.

Further Readings:

Brahma Sutra II.i.29 - 37

Brahma Sutra - II.ii.11 - 17