Can you be certain that it is truly non-doubt?

It is said that scientists used instruments to determine that the Earth is oval-shaped, and almost everyone believed it—and it seems to be the kind of belief that is held with complete conviction, as if such belief had already taken deep root and become unalterable. If someone does not believe it, others will go and debate with them, even mocking and ridiculing them; yet this too is not true belief with true absence of doubt. Belief also has many levels; some people even believe firmly without doubt, convinced beyond question, without the slightest hesitation. But without personal verification, all such belief belongs to blind faith and superstitious faith, not to belief born of realization. Therefore doubt still exists; it is merely deep and hidden, not easy to observe.

Knowing that the Earth is oval-shaped is merely hearsay, not something seen with one's own eyes; it is knowledge the mind consciousness has gained from hearsay. Since the manas has not personally seen it, doubt has not been eliminated. Moreover, even what many people see with their own eyes may not necessarily be true and real; cases of seeing wrongly are extremely numerous—what the eyes see is not necessarily real—so the manas's doubt cannot be eliminated. Once some other condition arises, saying that the Earth is actually not oval-shaped but rhombus-shaped or triangular, quite a few people's former belief will waver and turn into disbelief.

Why can faith be changed? It is precisely because there has been no personal realization. No matter to what degree the mind consciousness is convinced, it is unreliable; once conditions change, the mind consciousness's doubt appears. Why? Because the manas never believed in the first place, and the manas has not eliminated doubt; once conditions change, without the support of the manas's personal realization, the mind consciousness becomes fickle and loses its backbone—or rather, the mind consciousness's backbone has always been the manas, and at critical moments it invariably turns with the manas. Only by truly seeing the Earth, by genuinely witnessing the Earth's shape in its entirety and from a macroscopic perspective, can the manas eliminate doubt and give rise to faith. In the future, even if conditions change, the manas will still believe firmly without doubt, and then the mind consciousness will follow the manas in firm, unwavering belief; even if the mind consciousness has doubt, it will not take effect, and it will still trust the manas.

 Some people say that as long as you yourself are convinced that you have eliminated the self-view (ātma-dṛṣṭi) and have no doubt, you have attained the first fruit. How childish and laughable such a claim is! Is a worldling's firm conviction without doubt reliable? If it were reliable, why are sentient beings so fickle, changing their belief at the slightest stir and ceasing to believe? If a worldling's conviction and absence of doubt were reliable, why did the Buddha say, "Beware of trusting your own mind, for your mind is not to be trusted," and that only upon attaining arhatship may one trust one's own mind?

Historically recorded figures who confirmed for others the elimination of self-view and the attainment of the fruits are, first, the Buddha himself during the Buddha's lifetime, and second, the Fourth Patriarch Prajñāgupta after the Buddha's parinirvāṇa. As for the Buddha, that goes without saying: with immeasurable wisdom and unlimited supernatural powers, he knew all things, and with the ability to know others' minds and the recollection of past lives (pūrvanivāsānusmṛti), he could know and see the thoughts of sentient beings exactly as they were; whether or not his disciples had attained the fruits, the Buddha could know immediately without even meeting them. As for the Fourth Patriarch Prajñāgupta, he had not only attained arhatship but also possessed great supernatural powers; he even personally subdued the various disturbances and harassments of Māra Pāpīyas, restoring purity to Buddhism.

Judging by the Fourth Patriarch's realization of liberation and his powers of recollection of past lives and knowledge of others' minds, he could of course also know immediately whether his disciples had attained the fruits, without error. Others who lack realization, whose wisdom and realization are insufficient, and who have no supernatural powers or spiritual strength, probably cannot observe others' states of mind as they truly are, and therefore cannot confirm for others whether they have attained the fruits. Those with extremely profound wisdom, who have attained the fruits countless times over successive lifetimes and are rich in experience, can confirm for others the matter of attaining the fruits truthfully even without supernatural powers; apart from such people, no one else has the ability or qualification to confirm attainment for others. How much less can a worldling confirm it for himself: lacking experience, errors of judgment are simply unavoidable, and the consequences wrought are unimaginable.

 Practicing the Buddhadharma should be even more pragmatic and rigorous than worldly affairs; one must not treat the Buddhadharma as child's play, thinking it is very simple. In fact, nothing is more difficult than the Buddhadharma, because sentient beings have been engaged in worldly affairs for beginningless kalpas and are far too unfamiliar and unpracticed with the Buddhadharma; added to this are layer upon layer of karmic obstructions, and the obstacles are often far greater than we can imagine. Therefore, studying the Buddha's teachings and cultivating practice in a down-to-earth manner is our proper duty; only thus can we avoid adding further karmic obstructions and afflictions and sinking deeper into the abyss of birth and death.