The Buddha as a source of knowledge
A key aspect of Dharmakīrti’s epistemological theory to bear in mind is that his overall purpose in writing his epistemological works seems to be to demonstrate that the teachings of the Buddha, and especially the four noble truths, are uniquely suited to guide people to the highest good, nirvana. Other theories of the nature of discontent, its causes and the means of eliminating it, being either demonstrably false or not demonstrably true, are said to be attended by a greater risk of failure than are the basic teachings of the Buddha.
PV 1.134: The Compassionate One is well versed in strategies for getting rid of discontent, because it is a difficult task to explain the goal, which is not within the range of the senses, and the means of attaining it.
Here Dharmakīrti clearly states his view that the goal of achieving nirvana, which is the same as the cessation of the causes of discontent, is not available to the senses. The knowledge necessary to achieve nirvana, therefore, is not considered to be a purely empirical matter. Rather, it requires the application of the intellectual faculty and is facilitated by the guidance of traditional Buddhist scriptures.
PV 1.135: Examining things through both reasoning and the traditional teachings, one [who desires nirvana] inquires into the cause of discontent through the particularities of discontent, and inquires also into the impermanence that characterizes it.
PV 1.136: Since one sees that there is no end of the effect so long as the cause remains, one inquires into what is incompatible with the cause in order to get rid of it.
PV 1.137: And the antidote to the cause is ascertained by knowing the nature of the cause. The cause is attachment, which is created by the concepts of self and ownership, and which become part of one’s character.
As Vasubandhu had done before him, Dharmakīrti spares no effort in showing that the Buddhist view of the human condition is uniquely capable of leading to nirvana, since Buddhism is alone in recognizing that there is no enduring self (ātman), and that a false belief in such a self is the root delusion from which spring all unhealthy mental states, such as desire and aversion, from which in turn arise all counterproductive and harmful verbal and bodily actions.
PV 1.138‒139: The realization that there is no self, which realization is incompatible with the cause, destroys it. The virtues and shortcomings of that cause become very clear to one who practices many methods repeatedly for a long time. And because of that lucidity of mind, the impression left by the cause is left behind.
PV 1.140: This is what differentiates the great sage from the solitary buddhas and others who attempt to help others. [Buddhist] education is held to be nothing but the constant practice of methods [of getting rid of the fundamental causes of discontent].
PV 1.141‒142: Since he first came into being [as a Buddha] because of the perfection [of these two virtues, namely, the desire to help others and skill as a teacher], these two things are said to be the cause [of the Buddha]. The fact of being a Buddha, which comprises three virtues, consists in getting rid of the cause [of discontent]. His well-being stems from the fact that discontent has nowhere to stand in him, because he has realized that there is no self as well as because of his methodical reasoning. The production of birth and the production of vices [such as desire] are called rebirth.
PV 1:143‒144c: The end of rebirth comes from getting rid of the seed, namely, the view that there is a self. Because of alienation from that truth, remaining is without afflictions and torment with imperfections in body, speech and mind, or it is lack of skill in explaining the path. Getting rid of that completely is a result of practice.
The judgment that the words of the Buddha provide sound advice on how best to achieve nirvana is arrived at through a long chain of reasoning. One must use his words to infer the beliefs that he had in speaking them; then one must determine both that the Buddha was sincere in stating his beliefs and that his beliefs were correct. And the task of determining whether or not the Buddha’s beliefs were correct requires that one be able to find some independent means of verifying what he said, a means that does not depend solely on one’s unwarranted confidence in the Buddha’s wisdom and benevolent intentions.
One key question that required attention was: How can one assess the Buddha’s account of his own awakening?