1. The ātman is not an object of consciousness.

Question. – Why does the ātman not exist?

Answer. – We have already said above [when we were explaining the phrase] Evaṃ mayā śrutam ekasmin samaye (cf. Traité, I, p. 67–69F), but we will repeat it.

The Buddha spoke of six consciousnesses (vijñāna): 1) the eye consciousness (cakṣurvijñāna) and the dharmas associated with the eye consciousness (cakṣurvijñānasaṃprayukyakadharma) together take color (rūpa) as object (ālambana), but are not concerned with houses (gṛha), cities (nagara) and other nominal fictions of all kinds; 2–5) similarly, the consciousnesses of ear, nose, tongue and body (śrotraghrāṇajihvākāyavijñāna) [are concerned with sound (śabda), smell (gandha), taste (rasa) and touchable (spaṣṭavya) repectively]; 6. the mental consciousness (manovijñāna) and the dharmas associated with the mental consciousness (manovijñānasaṃprayuktakadharma) cognize the eye (cakṣus), color (rūpa), the eye consciousness (cakṣurvijñāna), and so on up to : they cognize the mind (manas), dharmas and the mental consciousness (manovijñāna).^[1]

The things that are the object (ālambana) of these consciousnesses (vijñāna) are all empty (śūnya), impersonal (anātman) and perish after their arising (utpannaniruddha); they are not independent (svatantra).

Neither can an ātman cannot be attributed to unconditioned dharmas (asaṃskṛtadharma),^[2] for they experience neither suffering (duḥkha) nor happiness (sukha). If an ātman were needed in all of that, there must be a seventh consciousness to cognize this ātman; but this is not the case. Therefore we know that there is no ātman.

Footnotes and references:

[1]:

According to the Kośa, IX, p. 238, the Vātsīputrīyas believe that the ātman or pudgala is cognized by the visual consciousness. When the visual consciousness, they say, cognizes color and shape, i.e., the body, they secondarily discern the pudgala (chakusurvijñeyāni rūpāṇi pratītiya pudgalaṃ prativibhāvayati). – Here the Mppś establishes that the object belonging to the six consciousnesses is empty and does not constitute an ātman; it will add that there is no seventh consciousness to cognize the ātman. This difficulty will later lead the idealist school to posit a seventh consciousness which they call the kliṣṭamanas. Stained by belief in a self, this kliṣṭamanas has the store-consciousness (ālayavijñāna) as object which it wrongly takes to be an ātman (cf. Saṃgraha, p. 16–22; Triṃśikā, p. 22–24; Siddhi, p. 225–288).

[2]:

These asaṃskṛta dharmas are space (ākāśa), cessation (= nirvāṇa) due to wisdom (pratisaṃkhyānirodha) and the cessation not due to wisdom (apratisaṃkhyanirodha); cf. Kośa, I, p. 8.