The all-basis is what falls away when we recognize our nature.
Could you elaborate on this, or provide a reference please?
The nature of mind is 'non-dual emptiness and clarity', so either (i) clarity (cognizance) must be recognized as empty, or (ii) emptiness must be recognized as non-dual with clarity.
The all-basis [skt. ālaya, tib. kun gzhi] essentially represents non-recognition of our nature, and so is naturally implied if we aren't in recognition of our nature. Differentiating mind and vidyā, or the all-basis and vidyā, mind and the nature of mind, ālaya and dharmakāya, etc., is a common theme in Dzogchen.
Clarity (cognizance) alone implies a subtle reference point and a subtle grasping, but when clarity is sealed with emptiness that reference point is freed up and the grasping is cut. cl
Clarity alone (divorced of the recognition of its emptiness) is merely the neutral indeterminate cognizance of the ālaya. All sentient beings function from the standpoint of the ālaya.
There's (i) non-fixation which is resting in the clarity of mind (as a reference point), and then there's (ii) non-fixation resting in the nature of mind (free of a reference point). Confusing the former for the latter causes a lot of issues.
Dudjom Rinpoche points out the difference between the ālaya and vidyā [rig pa]:"When the mind starts to rest, a slight diminishment of movement and thoughts constitutes a false semblance of stillness. When deep certainty arises that stillness is unborn and movement unceasing, and that stillness and movement are an equal taste, you have begun to meditate correctly."
The ālaya is the deluded reference point of mind which abides as the 'stillness' behind the movement of thought. This is also the clarity of mind. The deep certainty he's alluding to is the recognition of the mind's nature, where that clarity (i.e. stillness) is recognized as empty (or unborn as he puts it). Instead of the background stillness or clarity, it's recognized that the stillness was only ever precisely the movement of thought and phenomena, and that 'cognizance' is precisely the 'forms' of experience, at that point 'stillness and movement are an equal taste' as Dudjom Rinpoche put it, and that is knowledge of the mind's nature, which is vidyā [rig pa]. 'Meditating correctly' in this context means authentic vipaśyanā i.e. resting in the natural state.
The Reverberation of Sound Tantra explains the etymology of 'all-basis':"The etymology of 'kun' [all] lies in it's subsuming everything.
The etymology of 'gzhi' [basis] lies in it's accumulation and hoarding (of karmic traces and propensities)."
The same text continues:"Here I will explain the all-basis to start off:
It is the ground of all phenomena and non-phenomena."
The Tantra of the Self-Arisen Vidyā states:"The all-basis [skt. ālaya, tib. kun gzhi] is adulterated by diverse cognitive processes
By force of it's sustaining neurotic conceptuality;
The all-basis is the real ignorance [skt. avidyā, tib. ma rig pa]."
Jigme Lingpa in 'Distinguishing The Three Essential Points of Dzogchen' states:"The ālaya is the basis of all samsara and nirvana;
It is not unlike muddy water.
[In it], because of confusion led by latent ignorance,
The brightness of wisdom and gnosis has become hidden."
Elsewhere he states:"Those who, not understanding this, mistake the ālaya for the dharmakāya, are like blind men wandering in the desert without a guide. Because of their confusion about the vital points of the basis and result, they have come to a standstill on the path that accomplishes buddhahood in one lifetime."