The third variety of Pravacananihnavas (the apostasy which disowns (or denies) any one doctrine propounded by the Āgama (2) (canonical work) (and propounds his own));
the view (put forward by an apostate), which denies the truth; a kind of scepticism, according to which nothing can be said certainly about anything; everything is uncertain and inexpressible.
avyaktaṃ- asphuṭaṃ vastu abhyupagamato vidyate yeṣāṃ te'vyaktikāḥ, saṃyatādyavagame sandigdhabuddhaya iti bhāvanā.
(Sthā 7.140 Vṛ Pa 389)