Nyāya Sūtras 23

Where, however, there is cessation, where there is conclusion, that is—

Final liberation is absolute release from that.

From that—namely from pain, from birth—absolute release is final liberation. How? The abandonment of the birth that had been acquired, and the non-acquisition of another. Those who know final liberation understand this endless state to be final liberation. That is the fearless, ageless, deathless state, brahman, the attainment of ultimate security.

Some think: 'The eternal pleasure of the self, like its omnipresence, is manifested in liberation; manifested by which, the absolutely liberated one shines forth as joyful.' This is untenable for them, due to the absence of any means of valid cognition. Neither perception, nor inference, nor testimony exists to show that the eternal pleasure of the self, like its omnipresence, is manifested in liberation. The manifestation of an eternal thing is its sensation; its cause must be stated. The manifestation of an eternal thing is sensation, that is to say, cognition; its cause must be stated, from which it arises.

If it be said that [this sensation] is eternal like the pleasure itself? Then there would be no distinction between one who remains in saṃsāra and one who is liberated. Just as the liberated one would be endowed with pleasure and with the continuous eternal sensation of it, so too, it would follow, would one who remains in saṃsāra, because both are eternal.

And if this were conceded, accompaniment and simultaneity with the fruit of merit and demerit would be perceived. That pleasure or pain which is experienced alternately in the various places of birth as the fruit of merit and demerit, would be perceived to coexist and occur simultaneously with that eternal sensation; for there is neither absence of pleasure nor non-manifestation, because both are eternal. [Next,] stating the cause if it is non-eternal: if the sensation of eternal pleasure in liberation is non-eternal, the cause from which it arises must be stated. Contact between self and mind having another auxiliary cause as its cause: if it be said that contact between self and mind is the cause, even so, its auxiliary operative cause must be stated. Stating the cause of merit: if merit is that operative cause, the cause from which it arises must be stated. If it is destroyed, because what is produced by yogic concentration conflicts with the cessation of effects, the sensation ceases: if merit produced by yogic concentration is the cause?

[If it is argued that] merit born of yogic concentration is the cause—because it conflicts with the cessation of its effect, when [that merit] is exhausted, consciousness [of pleasure] ceases completely.
And in the absence of consciousness, there is no difference from what does not exist. If [you say that] due to the exhaustion of merit consciousness ceases, and eternal pleasure is not experienced, then whether what exists is not experienced or what does not exist [is not experienced], there is no inference [to establish] anything specific.
And the non-exhaustion of merit is devoid of inference, because it has the property of being produced. There is no inference that merit born of yogic concentration is not exhausted; rather, there is an inference to the contrary: that whatever has the property of being produced is non-eternal. But for one who holds that there is no cessation of consciousness, it must be inferred that the cause of consciousness is eternal.
And if it is eternal, as has been said, there would be no difference between the liberated [soul] and one remaining in worldly existence. Just as the liberated soul has eternal pleasure and the cause of consciousness of it, and there is no cessation of consciousness because the cause is eternal, so it would also be for one remaining in worldly existence. And this being so, co-occurrence with the consciousness of pleasure and pain, which is the fruit of merit and demerit, would be apprehended.
If it is argued that connection with a body and so forth is the cause of obstruction—no, because the body and so forth are for the sake of experience, and because there is no inference to the contrary.

It might be thought: for one in the state of worldly existence, connection with a body and so forth obstructs the cause of consciousness of eternal pleasure, and therefore there is no lack of difference. But this is improper: the body and so forth are for the sake of experience; it is untenable that they would bring about an obstruction of experience. Nor is there any inference that an incorporeal self has any experience at all.

If it is argued that activity is for the sake of attaining what is desired—no, because it is for the sake of the cessation of what is undesired. This is the inference: teaching on liberation and the activity of seekers of liberation are for the sake of attaining what is desired, neither being purposeless. But this is improper: teaching on liberation and the activity of seekers of liberation are for the sake of the cessation of what is undesired. Nothing desired can occur without being intermingled with what is undesired; hence even what is desired turns out to be undesired, and striving to get rid of the undesired, one abandons even the desired, because abandoning them discriminately is impossible.
And going beyond what is observed applies equally to the body and so forth. Just as, abandoning observed non-eternal pleasure, one desires eternal pleasure, so going beyond the observed non-eternal body, sense organs, and cognitions, an eternal body, sense organs, and cognitions would have to be postulated for the liberated soul; and thus the complete unity of the liberated soul would be more appropriately postulated.
If it is argued that this is contradicted by reasoned grounds—it is the same. If it is said that the eternity of the body and so forth cannot be postulated because it is contradicted by the means of valid cognition, it is the same: the eternity of pleasure also cannot be postulated because it is contradicted by the means of valid cognition.
And even if there is scripture, there is no contradiction, because the word 'pleasure' refers to the absolute absence of worldly pain. Even if there were some scripture stating that the liberated soul has absolute pleasure,

it is justifiable in this way: the word 'pleasure' is applied to the absolute absence of pain, for the use of the word 'pleasure' for the absence of pain is frequently observed in the world.
If attachment to eternal pleasure is not abandoned, there is no attainment of liberation, because attachment is recognized as a bond. If this liberation is [thought to be] eternal pleasure becoming manifest, one who strives for liberation out of attachment to eternal pleasure would not attain liberation; he cannot attain it. For attachment is recognized as a bond, and it is not tenable that anyone is liberated while a bond still exists.
[If it is argued that] for one who has abandoned attachment to eternal pleasure, there is no adversity—if now his attachment to eternal pleasure is abandoned, once it is abandoned, attachment to eternal pleasure is not adverse to him? If so, whether the liberated soul has eternal pleasure or does not have it, on neither thesis is his attainment of liberation called into question. //22