Does Ramanujacharya believe that inhabitants of Brahmaloka attain Moksha when they die?
Ramanujacharya is not stating his own view. Rather, he is stating a Purvapaksha argument which Badari refutes in the next Sutra (Sutra 9). Here is how this PDF presents Ramanujacharya's commentary on Sutra 9.
With the dissolution of the of the world of HiraNyagarbha along with him the soul of the one who has reached there goes beyond . So it is stated.
There is a further objection that if the individual soul goes to the world of HiraNyagarbha the texts that state the attainment of immortality such as 'thayOrDhvamAyAn amrthathvamEthi, (Chan.4-15-6) will have no meaning as according to the statement of the Lord in the Gita 'AbrhambuvanAllOkAh punarAvrtthinO arjuna, the worlds upto that of Brahma are subject to return.' Also because the scriptures state the dissolutin of HiraNyagarbha at the end of the period known as dviparArDHa.
To this BAdhari replies...
The portion in bold is what Ramanujacharya says at the end of his commentary on Sutra 8. And Badari's refutation of it is that although the inhabitants of Brahmaloka may be subject to rebirth, they do not actually get reborn because they will acquire knowledge of Brahman and thus attain Moksha at the end of the Mahakalpa.
For further confirmation, we can examine Adi Shankaracharya's commentaries on these same Sutras, and see that they have the exact same structure. Here is Adi Shankaracharya's commentary on the equivalent Sutra 8 (his numbering is different:
The word 'but' indicates the setting aside of the doubt.--As the lower Brahman is in proximity to the higher one, there is nothing unreasonable in the word 'Brahman' being applied to the former also. For when the higher Brahman is, for the purposes of pious meditation, described as possessing certain effected qualities--such as consisting of mind and the rest--which qualities depend on its connexion with certain pure limiting adjuncts; then it is what we call the lower Brahman.--But with the assumption of the lower Brahman there does not agree what scripture says about the souls not returning; for there is no permanence anywhere apart from the highest Brahman. And scripture declares that those who have set out on the road of the gods do not return, 'They who proceed on that path do not return to the life of man' (Kh. Up. IV, 15, 6); 'For them there is no return here' (Bri. Up. VI, 2, 15); 'Moving upwards by that a man reaches immortality' (Kh. Up. VIII, 6, 5).
To this objection we make the following reply.
And then he makes the same refutation in his commentary on the following Sutra:
When the reabsorption of the effected Brahman world draws near, the souls in which meanwhile perfect knowledge has sprung up proceed, together with Hiranyagarbha the ruler of that world, to 'what is higher than that i.e. to the pure highest place of Vishnu. This is the release by successive steps which we have to accept on the basis of the scriptural declarations about the non-return of the souls. For we have shown that the Highest cannot be directly reached by the act of going.
I discuss about the use of the term "place of Vishnu" in my question here, by the way.
In any case, now that we know that Ramanujacharya is not actually stating his own view in the passage I quoted, it follows that the only positions of Badari's and Jaimini that Ramanujacharya disputes are the ones he discusses in his commentaries in Sutra 14 and Sutra 15, where he discusses Badarayana's views.
So here is what Ramanujacharya actually believes:
If someone meditates on Hiranyagarbha (Brahma), then when they die, they don't go along the path of the gods outlined in the Panchagni Vidya. Rather, they just go to Brahmaloka. Then they attain knowledge of Brahman, and at the end of the Mahakalpa they attain Moksha along with Brahma.
If someone meditates on the supreme Brahman, then when they die, they immediately attain Moksha, by ascending along the path of the gods outlined in the Panchagni Vidya.
So everything makes sense after all! It's similar to how I thought I found an inconsistency in the work of Adi Shankaracharya here, and there turned out to be an explanation. It is a testament to these great thinkers that the coherence of their work stands up to such scrutiny.
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