How to Use Thesis, Reason, and Example in Argumentation

The Buddhist logic (hetuvidyā) used by bodhisattvas is called thesis, reason, and example (宗因喻). The thesis is the main proposition or viewpoint, the reason is the theory to be expounded, and the example is the analogy, instance, and fact. How are thesis, reason, and example to be employed? Let us illustrate with an example.

Someone says that the manas is one of the six faculties and, like the five physical faculties, is a material faculty. After we have engaged in logical reasoning that accords with the Dharma, we proceed to argue and expound: the manas is not a material faculty but a non-material faculty. The topic to be argued first—that is, the viewpoint, the notion, and the proposition—is: the manas is a non-material faculty. Once the proposition is put forward, it must be expounded comprehensively and completely, with arguments and reasoning presented. After the ideas have been clearly expounded, concrete instances are then adduced as evidence, letting the facts speak. In this way, the theoretical arguments are tightly bound to the proposition, and the concrete instances are tightly bound to the argumentation and the ideas, each link interlocking with the next, tightly sealed without any gaps. This carries the strongest persuasive power; even if someone objects, they cannot articulate any grounds for objection. If one opposes merely for the sake of opposing, or debates merely for the sake of debating, then both the opposition and the debate are ineffectual.

Of course, if one lacks rigorous logical reasoning and one's power of wisdom is insufficient, the arguments will be inadequate, lacking strong theoretical support, and the content expounded will fail to demonstrate the correctness of the proposition. If the reasoning is not rigorous and the exposition is not comprehensive, there will be gaps and loopholes, lacking persuasive power, insufficient to convince others. If the examples cited are far-fetched and cannot serve to support the correctness and soundness of the arguments, the persuasive power of the arguments will also be greatly diminished, unable to win people over. The capacity for logical reasoning reflects a practitioner's level of wisdom: the stronger the wisdom, the more meticulous the reasoning, the more powerful the capacity for logical argument, the more persuasive it becomes, and the greater the ability to deliver sentient beings. Those who practice the bodhisattva path, when encountering problems, should engage in deep and detailed contemplative practice (vipaśyanā-caryā), continually enhancing their own capacity for logical reasoning and observation. Of course, the prerequisite is very deep meditative concentration (samādhi); when reasoning is needed, one can then cast aside all distractions and concentrate on deep and careful deliberation, and only then can problems be resolved.