To what degree must the cognition of the mind reach before it can be called wisdom?

The cognitive mind's understanding of the Dharma is divided into different degrees. Cognition heavily obscured by afflictions is generally wrong view (mithyā-dṛṣṭi); cognition with somewhat lighter afflictive obstruction is sometimes correct, but only relative to one's previous mistaken understanding—it is not yet completely correct. Its views have merely been turned somewhat in the right direction, and the cognitive mind has gained some power of wisdom (prajñā-bala), but it still cannot be called wisdom (jñāna). Wisdom is correct cognition after there is no afflictive obstruction; because there is no afflictive obstruction, the cognitive mind's cognition has no afflictive or defiled nature, and can very clearly reveal its purity. What it creates is all wholesome karma and pure karma, and it will not create unwholesome karma. At this point, wisdom is almost free of error, or has very little error, and is worthy of trust and reliance—only then can it be called wisdom (jñāna). 

When the Buddha was on the verge of parinirvāṇa, He instructed sentient beings of later generations to rely on wisdom, not on consciousness. This wisdom is not the wisdom of ordinary intelligence, nor is it the wisdom of the acceptance of non-arising that arises right after attaining the fruits and seeing the mind; rather, it is the wisdom of the acceptance of the non-arising of dharmas that is free of afflictive obstruction, the wisdom that comes after transforming consciousness into wisdom, the wisdom of the wisdom of the varieties of paths. Right after attaining the fruits and seeing the mind, although one's wisdom is somewhat deeper than that of ordinary beings, because there is still afflictive obstruction, the wisdom remains rather shallow, and the defilement of the mind is still quite evident; sometimes one may even create some unwholesome karma due to afflictions. This is not yet wisdom, so one's understanding of the Dharma can only be called wisdom-in-training (prajñā), and cannot be termed wisdom (jñāna). As long as the outcome has a harmful effect, it is not wise and cannot be called wisdom; only when the results are all wholesome is the action a wise one, and only then can it be called wisdom and be relied upon. 

Whatever ordinary beings' mind consciousness thinks and contemplates is all of the nature of consciousness; the discerning and deciding functions that arise relying on the inertia of afflictions all belong to the nature of consciousness, without wisdom. For noble persons who have attained the fruits and seen the mind but have not eradicated afflictions, their thinking has a certain degree of wisdom; the strengthened power of wisdom (prajñā-bala) of the cognitive mind is called prajñā, but it is not yet wisdom (jñāna), and on the whole it still falls within the domain of the nature of consciousness, and cannot be fully relied upon. Therefore, many people, after learning some Dharma, consider themselves how superior and transcendent—this all falls within the scope of cognition of the nature of consciousness, in which the proportion of error is still very, very great. So one should not trust one's own mind too much; such self-confidence is almost mistaken trust, a result brought about by the mental factor of pride. For many people, what they themselves consider to be non-doubt is also not truly non-doubt; when wisdom is insufficient, even when there is doubt, one cannot detect it through introspection, and what one takes to be fact is often not fact at all—it is merely a misjudgment.