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Reasoning Tools for Deontic Logic and Applications to Indian Sacred Texts

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» What happens when commands clash?«

What happens when commands clash? A standard devise to deal with the topic is the idea of taking one as a general rule and the other as a specific one. In Sanskrit, these are called, respectively, utsarga and apavāda. Mīmāṃsā authors have, however, other devices.

For instance, Kumārila, discusses the prohibition to perform violence and its seeming conflict with the ritual prescription to perform ritual killing within a given sacrifice. See his Commentary in verses (Ślokavārttika), chapter on Injunction (codanā) , vv. 223—224:

तेन सामान्यतः प्राप्तो विधिना न निवारितः ||
फलांशोपनिपातिन्या हिंसायाः प्रतिेषेधकः |

“Therefore the prohibition to killing, obtained in general applied and not stopped by another injunction, prohibits the killing when it pertains to the fruit-portion.''

Is this a case of a general rule overturned by a specific one (as claimed in [Kei Kataoka 2012], Is Killing Bad?)?

If it were so, we would have the general prohibition to perform violence (i.e. F(violence/T) which has to be read as `it is forbidden to do violence given T', where T stands for any situations) being overruled by the more specific obligation to perform ritual killing in a specific setting:

- F(violence/T)
- O(violence/sacrifice for Agni and Soma)

However, this is not the solution adopted by Kumārila. Rather, Kumārila's point is that the original prohibition to perform violence should be reconfigured as a prohibition regarding only violence as the result of the action, and not regarding instrumental violence.

That is, according to Kumārila, the Vedic prohibition to perform violence should not be read as F(violence/T) but as F(violence as a result/T), which does not conflict with O(instrumental violence).

Comments, as usual, welcome!

7 October 2020
Indology member team

» Denotation as complex and chronologically extended«

The prescriptive sentences of the Vedas (specifically in the Brāhmaṇas) are considered by the Mīmāṃsā philosophers to be of central importance, and they thus argue that the Vedas convey primarily something which must be done (kārya). This focus on the deontic language of the Vedas led the Mīmāṃsā philosophers to deliberate upon several aspects on the nature of language and meaning, and two distinct theories of verbal cognition – abhihitānvaya and anvitābhidhāna – were put forth by the Bhāṭṭa and Prābhākara Mīmāṃsakas respectively. Śālikanātha (800-900 CE) is arguably the most important thinker among the Prābhākara Mīmāṃsakas, and his Vākyārthamātṛkā is the locus classicus for the philosophical presentation of the Prābhākara doctrine.

In a talk presented at the 9th Coffee Break Conference on Science and Technology in Premodern Asia (University of Oxford), the project's Shishir Saxena discussed the specific manner in which Śālikanātha defines abhidhāna or denotation, how this is distinct from the corresponding conception of the Bhāṭṭas, and the fundamental significance of this definition of denotation in Śālikanātha’s overall theory of anvitābhidhāna. This theory is especially crucial to understand since, according to Śālikanātha himself, it forms the basis (mūla) for the Prābhākara doctrine that all sentences have a deontic meaning, a formerly unknown thing which must be done (apūrvakārya).

15 January 2019
Indology member team

» On bādha and belief-revision in Mīmāṃsā«

What is bādha?: bādha is a way of dealing with contrasting Vedic rules, so as to know what to do when they seem to clash. E.g., what shall we do when we encounter a prescription telling us to do X and then one telling us not to do X?

How is bādha dealt with? Śabara's investigation on the problem starts by asking what exactly is bādhita `blocked' in such cases. Is it something already obtained (prāpta) or not? If it was already obtained to our treasure of knowledge, how can it then later be blocked without invalidating the epistemological status of the Veda? If it was not yet obtained, how can it be blocked?

The discussions on bādha become longer and longer in Kumārila's commentary on Śabara and then in Somanātha's sub-commentary on Kumārila. Somanātha explains that in case of bādha what happens is not that a later prescription or prohibition invalidates a previous one, for the reasons just said. Rather, what is blocked is only one's understanding of that precept. One thought at first that "Do X" meant "Do X in all cases", but after having heard "Do not do X in case of y", one revises one's understanding and comes to interpret "Do X" as "Do X in all cases apart from y". Thus, the initial prescription is rephrased as referring to all but the content of the later deontic statement (y-vyatirikta X). The first prescription had this restricted scope all the way long, so that no part of it is in fact invalidated, but one's belief is blocked and needs a revision. Somanātha speaks here of the need to take back one's previous opinion (buddhi-apahāra), not the existence of the epistemic content (viṣayasattva).

Somanātha articulates it in terms of the opposition between a sāmānyaśāstra 'general teaching' and a viśeṣaśātra 'particular teaching'. This is tantamount to the well-known principle of jurisprudence that Lex specialis derogat legi generali, but the interesting point is how exactly this occurs. In order to avoid endangering the validity of the first prescription's source, namely the Veda, Somanātha explains that the Veda initially produced only a cognition (jñāna), which is not necessarily valid, and that a specific understanding (vijñāna, interpreted as viśeṣa jñāna) comes about only thereafter, through the mechanism of bādha.

In some concluding verses he sums up the point by saying that as long as one looked at the Veda from a one-sided perspective (ekadeśa) one had a certain understanding of it. Later, through the completion of one's perspective (paripūrṇa), one also gets a full (samasta) understanding of the meaning at stake.

Why is bādha relevant (for us)? It is interesting for us because it can show us new ways of dealing with such problems and it can drive out attention to problems we would not have considered otherwise.

Who wrote about it? All Mīmāṃsā authors needed to deal with this problem. In a sense, bādha is the reason for the existence of Mīmāṃsā. Had the Veda not entailed any seeming contradictions, the Mīmāṃsā enterprise would not have been undertaken.

Do readers share the impression that what we are dealing with in Somanātha's interpretation is a device to account for belief-revision?

1 December 2018
Indology member team

» Various types of prescriptions vs. permission according to Maṇḍana «

How are duties and obligations conceived in Mīmāṃsā? Can Mīmāṃsā contribute to the deontic logic debate by suggesting alternative ways of conceiving duties and other deontic concepts, such as permissions and prohibitions?

In order to answer such questions, we looked in a text by Maṇḍana Miśra, the Vidhiviveka. This text is philosophically extremely rich, but its style is terse and hard to understand, so that no English translation has been prepared so far. The 8th c. Mīmāṃsā scholar Maṇḍana Miśra discusses exhortative statements in the Vidhiviveka by putting them all under the umbrella category of vidhi `prescription'. He distinguishes four types, namely ājñā `command', abhyarthana `order', anujñā `permission' and upadeśa `teaching'. The first three are distinguished according to the power and authority relation between the commander and the commandee. The latter category, by contrast, comprises prescriptions which are independent of the people who utter them, like in the case of laws. The main distinction between permission and the other types of prescriptions in Maṇḍana (as interpreted by his commentator Vācaspati) seems to be that other prescriptions, e.g., teaching, cause people to act, whereas a permission merely allows to someone who had already initiated an action out of her own will to continue acting. In other words, the addressee of the permission does not act because of the permission itself, but rather because of her own wish. For this reason, in the case of permissions there is no enjoined person (niyojya).

Further, a teaching is distinguished from a command insofar as the latter is uttered for the purpose of the commander, whereas the former is for the purpose of the person enjoined (since there is no enjoiner for a teaching, it cannot have the enjoiner as purpose). The permission, writes Vācaspati, may behave in the same way (i.e., it is not for the purpose of the person uttering it), but still it is distinguished from the teaching since the teaching causes people to act and the permission does not.

13 February 2018
Indology member team

» Mīmāṃsā, Deontic Logic, and Machine Ethics «

Reasoning about machine ethics is a very important and controversial topic, as witnessed, e.g., by the recent Report on Automated and Connected Driving issued by the Ethics Commission of the German Federal Ministry of Transport and Digital Infrastructure. The report points out that while genuine dilemmatic decisions can not be clearly standardized, nor can they be programmed such that they are ethically unquestionable (p.11), under certain circumstances [p]rogramming to minimize the number of victims [...] could [...] be justified, at any rate without breaching [...] the Basic Law (p.18). How can we specify such ethical obligations a program is required to meet? As suggested here, This question necessitates the study of logics of ethics and obligations.

1 December 2017
Logic member team

» Maṇḍana on the Śyena «

We already discussed (on November the 30th 2017) Jayanta's position on the Śyena sacrifice. In this post we will observe that Jayanta was in fact inspired by Maṇḍana and, perhaps, by Maṇḍana's commentator Vācaspati (it is still unsure whether Vācaspati was inspired by Jayanta or the other way around). According to Maṇḍana, there are two kinds of Vedic prescriptions, the ones regarding the person (puruṣārtha) and the ones regarding the sacrifice (kratvartha). In the case of puruṣārtha actions, the Vedic prescriptions do not motivate people to undertake them, since one would undertake them anyway because thery lead to happiness. Rather, the Vedic prescriptions motivate people to undertake these actions with a certain set of auxiliaries. Similarly, in the case of the Śyena, the prescription about it do not promote it, since it is in itself puruṣārtha. The Śyena remains an anartha„. (VV, p. 279, Goswami edition) (ef and Sudipta Munsi)

24 January 2018
Indology member team

» Jayanta on the Śyena «

According to Jayanta, the Veda only tells you how to perform something you already decided to carry out. The trigger of your (objectionable) action is not the Veda, but rather you. The Veda only gives you the instrument. Jayanta shows that this is the case through his analysis of the prescription regarding the Śyena, namely "The one who desires to kill his enemy should sacrifice bewitching with the Śyena'':

„Therefore, the Śyena and [the other malefic sacrifices], are not dharma. In their case, in fact, through the active present participle suffix (śatṛ) in `bewitching' the one who desires to kill his enemy with a Vedic means is shown to be the adhikārin of it (Śyena sacrifice). In this case, it is not the case that the Veda is the trigger. For he (the adhikārin) thinks: "I know that this has to be done by me, only the means is not known by me''. The Śyena-[passage] only teaches the means. There is no prescription saying "Perform the Śyena'', since the sheer desire to injure is the trigger for that (performance of the Śyena). Therefore, since Śyena etc. are not dharma, there is the employment (upādāna) of the word artha for the sake of excluding them [from the definition of dharma] in "Dharma is the artha conveyed by Vedic prescriptions'' (PMS 1.1.2).'' Therefore, the violence [prescribed] in the case of the offering to Agni and Soma is not adharma. The prohibition "One should not perform violence on any living being'' is a general teaching. And a general teaching functions only after excluded the content of the particular teaching (which means that a general rule excludes from its precinct of application the particular rule). Therefore, since the violence prescribed in the case of the offering to Agni and Soma is prescribed by the Veda, the prohibition (to perform any violence) does not communicate that [the above-mentioned violence] is an anartha„. (NM, book 5, vākyārtha)
(ef and Sudipta Munsi)

30 November 2017
Indology member team

» Reasons for formalising «

I am constantly confronted with the problem of why going through the ordeal of formalised language in order to better understand Mīmāṃsā. Therefore, here are some advantages of formalisation:

  • A. clarification (I definitely understood better why, e.g., the distinction between prescriptions and prohibitions is so important once I saw that "Ought not to X" cannot be translated into "Forbidden to X" and vice versa).
  • B. hermeneutic circle 1 (I looked for (and found) things I was not sure I should be looking for, e.g., a statement of the principle of non contradiction)
  • C. hermeneutic circle 2 (I revised my understanding of things)

  • An example of C regards the case of the yathāśakti principle applying to auxiliaries of fixed sacrifices. Mīmāṃsā authors distinguish between obligations regarding fixed sacrifices and elective sacrifices. The former have to be performed anyway, e.g., every morning and evening. The latter have only to be performed if you desire their outcome, e.g., a son, cattle or rain. Thus, you have a stronger obligation in the first case and a weaker obligation in the second case. The subsidiaries of elective sacrifices are to be performed at all costs, in the sense that you are not allowed to undertake an elective sacrifice unless you are able to perform all its subsidiaries. By contrast, the subsidiaries of fixed sacrifices are only obligatory according to the yathāśakti principle, i.e., insofar as one can perform them. Now, until now I thought that there was a symmetric relation between fixed and elective sacrifices and their auxiliaries, so that a strong obligation for the sacrifice meant a weak obligation for its auxiliaries and a weak obligation for the sacrifice meant a strong obligation for its auxiliaries. Working with my colleagues of the logic department, however, I saw that in fact there are two types of weak obligation. The one regarding elective sacrifices is akin to a recommendation (``If you desire X, it is recommended to perform sacrifice Y"). By contrast, the one regarding the auxiliaries of a fixed sacrifice entails an alethic element (``If you can perform X, you ought to perform X"). (ef)

    7 November 2017
    Indology member team

    » Śyena reinterpreted: You can kill your enemy, if he is about to kill you «

    The Śyena sacrifice is a sacrifice aiming at the death of one's enemy. The usual interpretation of the Śyena sacrifice is that you just don't perform it, because it is violent and violence is prohibited (unless it is performed as an element of a rite, e.g., in the Agnīṣomīya). Here comes, however, a novel interpretation: "For Mīmāṃsā, it is not the case that violence in itself is the cause for pāpa (evil karman), only prohibited violence is. The killing of the sacrificial animal performed within the Jyotiṣṭoma is [just] effecting that the sacrifice is complete with all its elements. Out of the result of the Śyena sacrifice anartha is produced. Out of this result, which consists in the killing of one's enemy, there is anartha in the form o reaching suffering, i.e., hell. [For] the killing of one's enemy, which is the result of the Śyena sacrifice, is not known through a prescription. However, If the enemy is already ready to kill (ātatāyin), then his killing is prescribed. Since in that case violence is prescribed, the Śyena sacrifice does not produce anartha. Therefore, it is established that the Śyena sacrifice does not in itself lead to anartha as result." (p. 25 of Rāmaśaṅkara Bhaṭṭācārya's commentary (called Jyotiṣmatī) on Sāṃkhyatattvakaumudī) The author of this work, Dr. Ram Shankar Bhattacharya (1927-1996), was a scholar of international repute, well-known for his ground-breaking works in the field of Indological scholarship in general and Sanskrit in particular. He was a pupil of Hariharānanda Āraṇya and then of his successor, Dharmamegha Āraṇya. He has at least 30 works and hundreds of articles in various languages (English, Bengali, Hindi and Sanskrit) dealing with Purāṇas, Sānkhya and Yoga philosophies, Sanskrit grammar, Indian History, etc. to his credit. He co-edited (along with Prof. Gerald James Larson) the volumes on Sānkhya and Yoga philosophies of the Encyclopaedia of Indian Philosophies series, published under the general editorship of Karl H. Potter, by M/S Motilal Banarsidass. He also served as the scholar-in-residence (sabhāpaṇḍita) of His Royal Highness, the King of Benaras, and the editor of the bi-annual multi-language journal, Purāṇam, published by the All-India Kashiraj Trust, for years, which contains innumerable research articles from his pen. Besides, he also edited four Purāṇas (Agni, Vāmana, Kūrma and Garuḍa) for the same institution. What remains to be researched, is what it means for an enemy to be ātatāyin (lit. `with one's bow stretched', i.e., ready to shoot). Should the enemy be literally about to kill one? If so, there would be no time to perform a Śyena sacrifice. So, either Rāmaśaṅkara Bhaṭṭācārya thinks of preventive actions against people who are known to be about to kill someone or his is just a theoretical discussion. In order to partly solve this problem, we checked the definition of ātatāyin in the Śabdakalpadruma (a famous Skt-Skt dictionary). This states `ready to kill' and then quotes a verse from the commentary of Śrīdhara on the BhG discussing six types of such villains: people who are about to set something on fire, poisoners, people with a sword or a knife (śastra) in their hands, robbers, people taking away one's wife or fields (perhaps: the products of one's fields?). Śrīdhara then concludes: ``There is no flaw in killing an ātatāyin". The Vācaspatyam (Skt-Skt) dictionary has a much longer entry. I am still not sure whether someone can be defined an ātatāyin for just plotting a killing ---something which would allow one to prepare and perform the Śyena sacrifice. Sudipta thinks that plotting should be included, since otherwise it might be too late to take action against the ātatāyin and the prescription about killing an ātatāyin found in Dharmaśāstra would be futile. Sudipta accordingly thinks that the Śyena is not prohibited in the case of preventing, e.g., a terrorist attack and that it is only prohibited if performed for one's own sake, as an offensive action. (This post has been jointly discussed by EF and Sudipta Munsi, who kindly showed me the quote mentioned above.) (ef)

    6 October 2017
    Indology member team

    » Do we need an operator for necessity? «

    I'm not convinced that it's necessary to add the square (meaning ''necessity'') to our system of axioms, depending on whether the variables refer to discrete states of affairs or classes of states of affairs. In other words, if you relativize the entire definition to a single person at a single point in time, then it doesn't seem to make a difference whether you say that a given action (l) is obligatory for him, given his desire for the result (r), if and only if he can bring r into being by doing l (provided that some other conditions are met). We discussed "possible worlds" in which l is not an instrument for the realization of r, but in those worlds presumably l would not be obligatory. However, it is right that the intuitive sense of an obligation requires some quantification over states of affairs; in fact Mīmāṃsā holds that a Vedic injunction makes us aware of an obligation that exists "outside of time" which ought to be fulfilled in an infinite series of future states of affairs whenever the relevant conditions are satisfied. (ao)

    3 July 2017
    Indology member team

    Some benefits of a deontic logic analysis for Sanskritists

    We are working on a new article on how prescriptions and prohibitions are conceived in early Mīmāṃsā and how these notions have been reshaped in its "golden age" by thinkers like Kumārila, Prabhākara and Maṇḍana. It seems that they tried to systematise concepts which were not fully developed before them, for instance, by translating all three deontic operators (the one for optional sacrifices, the one for conditional sacrifices and the one for fixed sacrifices) into a single one. Deontic logic will allow us to see clearly the problems Maṇḍana was dealing with and wanted to solve (for instance, the alternation of sanction and result in the identification of deontic operators) and to evaluate his impact. (ef)

    3 July 2017
    Indology member team

    » Why is it interesting to deal with Mīmāṃsā deontics? «

    Most deontic theories conflate two different approaches:

    The Mīmāṃsā approach is interesting exactly because it separates the two. In other words, suppose we say that a person ought to perform p because p is good or because it is God's will etc. In this case, you are using your ethical (and metaphysical) assumptions to ground the validity of your deontic statements. By contrast, Mīmāṃsā authors analyse deontic statements on their own. Just like they analyse the epistemic validity of statements independently of the authority of their authors, so they analysed the deontic validity of statements independently of a further background. This does not mean that it is, for instance, ethically good to bring to poverty all human beings. In fact, if you do that, you are surely transgressing the prohibitions to harm human beings and will get negative consequences (=negative karman) out of it. Still, you do not need ethical presuppositions to make sense of the Mīmāṃsā theory. (ef)

    27 June 2017
    Indology member team

    » Mīmāṃsā and Law «

    The Mīmāṃsā principles were created for religious purpose, namely for making sense of the Vedas. Nonetheless, they were so rational and logical that they subsequently began to be used in law, grammar, logic, philosophy.
    → See here. (ac)

    15 May 2017
    Logic member team