In Adhyaya 5 Pada 2 Sutra 1 of the Nyaya Sutras, Gautama lists the 22 argumentative moves that cause you to lose a debate, known as Nigrahasthanas or Clinchers:
pratijñāhāniḥ pratijñāntaraṃ pratijñāvirodhaḥ pratijñāsaṃnyāso hetvantaramarthāntaraṃ nirarthakam avijñātārtham apārthakam aprāptakālaṃ nyūnamadhikaṃ punaruktam ananubhāṣaṇam ajñānam apratibhā vikṣepo matānujñā paryanuyojyopekṣaṇaṃ niranuyojyānuyogopasiddhānto hetvābhāsāśca nigrahasthānāni
- Violating the Proposition
- Shifting the Proposition
- Contradicting the Proposition
- Renouncing the Proposition
- Shifting the Probans
- Meaningless Jargon
- Confession of a Contrary Opinion
- Overlooking the Censurable
- Censuring of the non-censurable
- Fallacious Probans
are the Clinchers
These terms are defined in the subsequent Sutras of Adhyaya 5 Pada 2:
- When the property of the counter-instance is admitted by one to be present in the example cited by himself, - it is the case of Violating the Proposition.
- The subject of the Proposition having been denied, if the First Party finds a diversity in the properties, and puts it forward with a view to establish the former Proposition, - this is Shifting the Proposition.
- When there is contradiction between the Proposition and the Probans, it is Contradiction of the Proposition.
- The original thesis having been opposed, if what was formerly opposed happens to be retracted, - it is Renouncing the Proposition.
- The probans in the unqualified form having been opposed., if the first
party denies to qualify it, it is a case of shifting the probans.
- The putting forward of statements bearing no connection with the
purpose in hand constitutes Irrelevancy.
- That which is like the mere repeating of the letters of the alphabet
is Meaningless Jargon.
- If the assertion made is such that, though stated three times, it
fails to be understood by the audience and the Second Party, it is a
case of Unintelligibility.
- In a case where, there being no connection between the expressions
following one another, they are found to afford no connected meaning,
it is a case of Incoherence.
- When the factors of reasoning are stated in the reversed order,
it is a case of Inconsequentiality.
- That which is wanting in any one of the factors of reasoning is the Incomplete.
- That which contains superfluous Probans and Example is the Redundant.
- The re-statement of Words and Ideas constitutes Repetition' -
except in the case of reproduction.
- The actual statement by means of directly expressive word of what
is already implied [is also Repetition].
- If the First Party fails to restate what has been stated three times, and duly understood by the audience, it is a case of Non-reproduction.
- When the statement is not comprehended, it is a case of Incomprehension.
- It is Embarassment when the Party does not know the answer.
- When the Party breaks off the discussion under the pretext of
business, it is a case of Evasion.
- If the Party admits the flaw in his own thesisi, and then urges the
same in that of the Opponent, - this is a case of Confessing
the contrary opinion.
- When one party has rendered himself subject to a Clincher, if the
other party fails to bring it home to him, - the latter himself becomes subject to the Clincher of Overlooking the Censurable.
- When one party urges a 'Clincher' when there is no 'Clincher'
(incurred by the other party),- it is a case of Censuring the
- Having taken up one standpoint, if the party carries on the discussion
without restriction, -it is a case of Inconsistency'.
- The Fallacious Probans also as they have been already described.
For examples illustrating these fallacies, see this portion of Vatsyayana's Nyaya Sutra Bhashya. Now as to matching them with Western terms, Shifting the Proposition corresponds to the "No True Scotsman" fallacy, Irrelevancy corresponds to the Red Herring Fallacy, and Confession of a Contrary Opinion corresponds to the Tu Quoque Fallacy. Some of the others are at least discussed as concepts in Western works, but they aren't recognized as named fallacies. And others have not even been discussed in Western works.
I should also say something about the last item listed, Hetvabhasa or Fallacious Probans. The first 21 items are what are called informal fallacies in Western terminology. But Fallacious Probans refers to general category logical fallacies. These are not enumerated above, because they were enumerated earlier in the Nyaya Sutras. Here is what Gautama says in Adhyaya 1 Pada 2 of the Nyaya Sutras:
- (1) The Savyabhichara (Inconclusive), (2) The Viruddha (Contradictory)
(3) The Prakaranasama (Neutralised), (4) The Sadhyasama (unknown),
and the Kalatita (Mistimed) - are the Fallacious Probans.
- The Inconclusive is that which is tainted by indecision.
- A certain doctrine ( or view) having been accepted, the Probans that
is contradictory to it is called the 'Contradictory'.
- The Neutralised Probans is that which is put forward to establish
a definitive conclusion, while it is one that only gives rise to
suspense (and vascillation) in regard to the point at issue.
- The Unknown Probans is that which, being still to be proved, is not
different from the Probandum.
- The Belated or Mistimed Probans is that which, as adduced, is behind
It should also be mentioned that there are also some weak and/or underhanded argumentative moves that do not cause you to lose a debate. They go by the names Chchala or Casuistry and Jati or Futile Rejoinders. These too are enumerated in detail in Adhyaya 1 Pada 2. When your opponent does one of these, you don't automatically win the debate, but Vatsyayana's Nyaya Sutra Bhashya tell you how to counter these moves and thereby win the debate.
May we all endeavor to avoid all these moves in our arguments!