Tibetan Collected Topics (bsDus grwa)
Origin. Tibetan monastic curriculum, systematized 12th-15th c. Cha-ba Chö-kyi Seng-ge, Sakya Pandita, later dGe-lugs codification. Debate training. Collected topics (bsdus grwa) as primer. Foundation of Tibetan Buddhist logic.
Models. Definitions, divisions, illustrations. Subjects and predicates. Pervasion (khyab pa). Colors and phenomena as training examples. Rigorous debate format.
Formalism.
Three components of definition: mtshan nyid: definition mtshon bya: definiendum mtshan gzhi: illustration/instance
Example: mtshan nyid: "that which is able to perform a function" (don byed nus pa) mtshon bya: functioning thing (dngos po) mtshan gzhi: a pot
Pervasion (khyab pa): A is pervaded by B: whatever is A is necessarily B. khyab pa: pervasion khyab byed: pervader (the larger class) khyab bya: pervaded (the smaller class)
Four relations of two phenomena:
- mutually inclusive (don gcig)
- four possibilities (mu bzhi)
- three possibilities (mu gsum)
- mutually exclusive (phan tshun spangs 'gal) Decided by which of the four corners are occupied.
Pervasion example: A = permanent (rtag pa) B = existent (yod pa) Both: space A not B: none, since whatever is permanent exists B not A: pot Neither: none, since nothing falls outside the existent Two corners only: A is pervaded by B. Not four possibilities, which needs all four occupied.
Debate format: Challenger (rigs lam pa): poses thesis Defender (dam bca' ba): accepts, rejects, or asks reason Responses: 'dod (accept), rtags ma grub (reason not established), khyab pa ma byung (pervasion not established)
Consequences (thal 'gyur): "It follows that X, because Y" Defender must accept, reject reason, or reject pervasion.
Types of phenomena: dngos po: functioning thing (impermanent) rtag pa: permanent gzugs: form shes pa: consciousness
Symbols.
| Symbol | Unicode | Name | Meaning |
|---|---|---|---|
| A | U+0041 | Latin capital letter A | First of the two classes compared |
| B | U+0042 | Latin capital letter B | Second class, the pervader where one pervades the other |
| ' | U+0027 | Apostrophe / a-chung | Wylie transliteration of the Tibetan letter འ |
| " | U+0022 | Quotation mark | Encloses a definition quoted in full |
| ( | U+0028 | Left parenthesis | Opens a Tibetan term or its gloss |
| ) | U+0029 | Right parenthesis | Closes it |
| : | U+003A | Colon | Separates a technical term from what it names |
| = | U+003D | Equals sign | Assigns a phenomenon to a class letter |
| khyab pa | — | Pervasion (ཁྱབ་པ) | Whatever is the one is necessarily the other |
| khyab byed | — | Pervader | The wider class |
| khyab bya | — | Pervaded | The narrower class |
| rjes khyab | — | Forward pervasion | Whatever bears the reason bears the predicate |
| ldog khyab | — | Reverse pervasion | Whatever lacks the predicate lacks the reason |
| thal 'gyur | — | Consequence (ཐལ་འགྱུར) | The form in which every thesis is put |
| chos can | — | Subject | What the consequence is about |
| rtags | — | Reason | The ground offered for the consequence |
| phyogs chos | — | Property of the subject | The reason holds of the subject |
| tshul gsum | — | Three modes | The conditions a reason must meet |
| mtshan nyid | — | Definition (མཚན་ཉིད) | The defining characteristic |
| mtshon bya | — | Definiendum | What the definition defines |
| mtshan gzhi | — | Illustration | An instance satisfying the definition |
| don gcig | — | Mutually inclusive | The two classes coincide |
| mu gsum | — | Three possibilities | Three of the four corners occupied |
| mu bzhi | — | Four possibilities (མུ་བཞི) | All four corners occupied |
| phan tshun spangs 'gal | — | Mutually exclusive | Nothing falls under both |
| med dgag | — | Non-affirming negation | Denies without putting anything in place of what is denied |
| ma yin dgag | — | Affirming negation | Denies and implies something in place of what is denied |
| 'dod | — | I accept | Respondent concedes the consequence |
| rtags ma grub | — | The reason is not established | Respondent denies that the reason holds of the subject |
| khyab pa ma byung | — | The pervasion does not follow | Respondent denies that the reason entails the predicate |
| rigs lam pa | — | Challenger | Poses the consequence |
| dam bca' ba | — | Defender | Answers it |
| dngos po | — | Functioning thing | Impermanent phenomenon |
| don byed nus pa | — | Able to perform a function | The definition of a functioning thing |
| rtag pa | — | Permanent | Phenomenon that performs no function |
| yod pa | — | Existent | The widest class |
| gzugs | — | Form | Material phenomenon |
| shes pa | — | Consciousness | Cognizing phenomenon |
Metatheory. The bsdus grwa is a debate manual and not an axiomatic system, so no completeness or decidability claim attaches to it; what it supplies instead is a fixed move set that can be checked mechanically. Every thesis is put as a consequence with three named parts — subject (chos can), predicate to be proved, and reason (rtags) — and the respondent is allowed exactly three replies, so each move either concedes or names which of the two conditions on a good reason has failed: that the reason holds of the subject (phyogs chos), or that the pervasion holds (khyab pa). Those conditions are Dharmakīrti's three modes (tshul gsum) regrouped, the second and third having been collapsed into forward and reverse pervasion (rjes khyab, ldog khyab), which are contrapositives and so stand or fall together. The fourfold classification of relations is exhaustive over pairs of non-empty classes that do not jointly exhaust the domain, and fails outside that condition: the pair of permanent and existent occupies only two corners, because nothing lies outside the existent, and so falls under none of the four. Termination is dialectical rather than semantic — the defender loses on being driven to contradict an earlier concession, so what the procedure tests is the consistency of the commitment record, not truth in a model.
Applies to. Tibetan monastic education. Buddhist philosophy training. Debate methodology. Logical pedagogy.
Limitations. There is no symbolic notation and no formation rules: arguments are stated in Tibetan on a fixed template, so there is no syntax for a proof-theoretic result to attach to, and validity is adjudicated by the assembly rather than decided by a procedure. Pervasion is the only conditional the system has, and it is a universally quantified one over classes, so there is no apparatus for nested or multiple quantifiers and no way to form a relational statement such as "every monk has a teacher." Connectives are absent as operators: negation is present, but the doctrinally important split between affirming and non-affirming negation (ma yin dgag, med dgag) is semantic and carries no mark in the template. The ontology is fixed rather than chosen — every phenomenon is permanent or impermanent, and the existent (yod pa) is the widest class — so empty terms fall outside the domain instead of being reasoned about, and the four-corner classification breaks down on any pair that exhausts the domain. The procedure refutes the defender, not the thesis, so a badly defended truth and a falsehood are indistinguishable by its outcome.
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