If there is a conflict between two verses of the Koran, or a verse of the Koran seems in conflict with an authentic tenet of the hadith, Muslim doctors of law propose the following harmonizations.
1st rule: exception.
If one text is more restricted in scope than a conflicting other, the narrower is considered an exception to the larger.
The major premise: “X is to do Y”;
the minor: “X is not to do Y, when Z”;
the putative conclusion: “X is to do Y, only when not Z”.
The conclusion renders the major premise conditional. This solution seems credible, granted both texts have comparable level of authority and reliability. Note that this rule is comparable to Rule 10 or perhaps 13 of R. Ishmael in Talmudic hermeneutics; it is a dialectical reconciliation.
2nd rule: merger.
If one text prescribes (or forbids) a part of some class and the other similarly prescribes (or forbids) another part of the same class, there is no contradiction: together the two texts form a larger proposition.
The major premise: “X is to do Y, when Z1”;
the minor: “X is to do Y, when Z2”;
the putative conclusion “X is to do Y, when Z1 or Z2 (or ‘when Z’, if Z1 and Z2 constitute all of Z)”.
This is a valid merger or amplification.
3rd rule: exclusion.
If one text prescribes (or forbids) to what seems a general subject (X) what seems a specific predicate (Y1), and another text obversely forbids (or prescribes) to what seems a specific subject (X1) what seems a general predicate (Y), then we must conclude that either the specific subject is not included in the general subject or the specific predicate is not included in the general predicate (the decision between these two alternatives depending on finding another text which comforts the one or the other).
The major premise: “All X are to do some Y1”;
the minor: “No X1 is to do any Y”;
the putative conclusion: “No X1 is X” and/or “No Y1 is Y”.
For, it is tacitly argued, if we add to the major and minor that “All X1 are X” (subjectal) and “All Y1 are Y” (predicatal), we must conclude that “All X1 are to do some Y” (pitting the minor against the three other premises) and “At least some X are not to do any Y1″ (pitting the major against the three other premises), by regular syllogisms and substitutions.
Note that in fact, it suffices for the subjectal premise to be “At least some X1 are X” to obtain the result “No X1 is X”. Also, given the needed generality of the predicatal premise, the second result should be “At least some Y1 are not Y”. But we can accept the generalities everywhere, granting that we are dealing in kinds, i.e. whole classes (to be precise, such acceptance involves a generalization). Also note, the disjunction in the conclusion may be taken as inclusive, and/or.
This is a credible resolution of conflict, granted both texts have the same level of authority and reliability. Comparing to Talmudic hermeneutics, this rule concerns a situation treated under Rule 10 of R. Ishmael; but whereas the latter resolves the conflict by a daring particularization of the major premise, the Islamic version more carefully challenges the subjectal or predicatal premise.
4th rule: abrogation.
If one text prescribes (or forbids) the entirety of what another text conversely forbids (or prescribes), one or the other text must be abrogated, i.e. considered null and void. If one is more recent, it is to be preferred. Otherwise, add certain commentators, if one is seemingly more demanding, it is to be preferred. But there are often disagreements, when such conflict resolutions are not readily available. (Another logically conceivable resolution, note, would be to particularize both premises to some extent—but I do not know if Islamic interpreters use this option.)
There is a Koranic text (2:106) saying that abrogation of a law occurs only when a better or similar one is promulgated (for some this implies that God, the author of the Koran, is the only abrogator or promulgator). This is understood at one level to refer to God’s abrogation through the Koran of some pre-Koranic laws. At a second reading, it may imply that there should be no unresolved contradictions within the Koran, which is doubtful considering the need for two of the previous three rules. Naturally, if one text has greater authority and reliability (e.g. Koran vs. hadith), it is to be preferred. But the law doctors wonder whether the lower text (hadith) may abrogate the higher (Koran) in certain cases.
On a formal level,
the major premise: “X is to do Y”;
the minor: “X is not to do Y”;
so, one or the other must indeed be abandoned in the conclusion.
The preference of the more recent (say, within the Koran, which is not chronologically ordered) is sound practice, though it is unclear why God would change His mind so quickly, before the earlier law has had time to be put into practice (if that is the case).
Concerning the subsidiary rule about the relative severities or leniencies of the two texts, the implication is that the two predicates are not really identical (Y).
Regarding conflicts between texts of unequal authority and reliability, I fail to see how the lower (hadith) can displace the higher (Koran), but I have not seen relevant examples.
We may add that it could be appropriate to use such a rule when there is a conflict between a text (Koran or hadith) and an established empirical fact; the latter winning, according to our modern view.
For comparison, abrogation is not officially included in Talmudic hermeneutics, though in practice it occurs (e.g. at least, when one rabbi’s position is preferred to another—but sometimes perhaps also in Torah contexts, as e.g. in the apparent conflict between Gen. 1:29 and 9:3).
There are some similarities between the above four rules and Talmudic harmonization rules. But the latter often consider more complex situations and propose more far-fetched logical responses. One significant underlying difference is the rabbinic concern with redundancies.
There are, additionally (mentioned in my said source), two types of reasoning by analogy.
This involves generalization. An issue, here, is why the original text did not mention the sought-for generality in the first place. In cases where the new cases were unknown at the time (e.g. electricity, say), this is understandable. But in other cases, the use of such reasoning may seem daring.
5th rule: extension by direct analogy.
A law given in the text concerning some particular case(s), may be extended to all other cases of the same sort. The difficulty with this method, as the law doctors admit, is the vagueness of the underlying criterion of resemblance. Formally,
“X1 is to do Y” and “X1 is an X”,
therefore “At least some X are to do Y”;
therefore “All X are to do Y”.
This is syllogism followed by generalization, which is in principle acceptable, so long as no reason is found for particularization. This method calls to mind that of gezerah shavah in Talmudic hermeneutics.
6th rule: extension by indirect analogy.
When a law found in the text concerns some particular case(s), the reason for the law is sought, before extending to all other cases which seem subject to the same underlying reason. Formally,
(a) the initial law is “X is to do Y” (textually given);
(b) furthermore, we presume that “X is to do Y, because X is Z” (not textually given);
(c) granting this, we are supposing that “All Z are to do Y” (not textually given).
The third proposition is seen as an explanation of the “because” clause in the second. For, with the propositions “X is Z” and “All Z are to do Y”, we can by syllogism infer the given premise “X is to do Y”. It is clear that propositions (b) and (c) are not inferred from (a); rather, we have sought out propositions from which (a) might be inferred. (b) and (c) are thus hypotheses which fit this requirement; but it does not follow that they are the only possible such hypotheses. So long as no alternative explanation of (a) is found, then (b) and (c) have some credibility. We have, then, at best an inductive argument, not a deductive one, note well.
This method resembles somewhat that of binyan av in Talmudic hermeneutics. It is called qiyas, and was developed by the imam Al-Shafii (d. 820). Another jurist, Ibn Hazm, also known as Abu Mohammed Ali (Spain, 994-1064), criticized this approach, arguing that God’s intent in the Koran was precisely what he said and no more (except where the text is put in doubt by another text).
7th rule: application.
Additionally, some Moslem commentators acknowledge syllogistic reasoning composed of a Koranic major premise and an observed minor premise. E.g. “Fermented drinks are forbidden” and “wine is a fermented drink”, therefore “wine is forbidden”. The issue here is whether the middle term is correctly interpreted.
My source further mentions the methods of istihsan (a law is proposed because it seems ‘good’) and istislah (a law is proposed because it seems ‘useful to the Community’), which institute laws not mentioned in the text, that is, through insight of their value. As some Moslem commentators have pointed out, such methods may be subjective and arbitrary, and lead far from the given text. Indeed, value-judgments are almost bound to be conditioned by personal and social/cultural context; they may easily be prejudices.
There is also the principle of consensus (ijma), which resembles the Talmudic principle of rov (majority). The Islamic principle is based on a hadith where Mohammed says “My Community will never agree together on an error”. The issue then arose, on a practical level—who to include in the ‘Community’? Democratically, it would be the whole population; this being at the time impracticable, the law doctors were referred to; but in view of communication difficulties in the vast Islamic empire, only those of major Islamic centers were considered. Some commentators suggested, instead, that the ‘Community’ included only the immediate companions of the Prophet.
The very fact that there are disagreements among authorities regarding the reference intended by the language of this hadith—as well as the practical difficulties of application of different interpretations—make such a rule of consensus open to doubt, and therefore ultimately to some extent arbitrary.
The above is probably not a complete list of hermeneutic rules used in developing Islamic law.
Note also that the formal representations of the rules proposed above are my own logical clarifications. The Islamic jurists who appealed to these techniques were not necessarily as clearly aware of their structures; and those who were theoretically aware, did not necessarily always manage to adhere to them in practice. Probably, some interpreters occasionally wrongly (through mistakes or dishonesty) claimed their judgments based on these ideal forms.
Anyway, the rules mentioned above seem overall respectable, from a logician’s point of view. Needless to say, this positive evaluation of some logical methods is not intended as a comment on the content of Islamic law, or as an expression of any sort of personal endorsement of Islam.
Incidentally, some Islamic methods resemble Talmudic ones, but the former are on the whole more natural. It is significant that the latter are often more artificial. This may be due to their being of earlier date historically; it shows anyhow that they are not universal to all religious groups, and therefore not normal to human reasoning. Nevertheless, apparently, Talmudic logic includes valid forms, like the a-fortiori argument, which are (to my knowledge so far) absent in Islamic methodology, at least at a self-conscious level.
Note, finally, the distinction between Divine law (shar), found written in the Koran and not giving rise to disagreements among law doctors; and Applied law (sharia), developed by law doctors, in response to textual conflicts or through other motives.
This distinction is similar to that between unproblematic Torah law, and Talmudic and Rabbinic interpretation of law (halakhah).
There are four main schools of interpreters of the law:
· the liberal Hanefists (Abu Hanifa, d. 767), found in Turkey, Central Asia, Pakistan and India;
· the Malekists (from Malik b. Anas, d. 795), dominant in North Africa;
· the Shafeists (Shafii, d. 820), especially in Egypt and Indonesia;
· and the rigid Hanbalists (Ahmad ibn Hanbal, d. 855), in Saudi Arabia.
A fifth school, not officially recognized, is that of the Zahirists (including ibn Hazm, already mentioned), which sought literal readings and rejected laws based on human reasoning. We might roughly compare these to the Sadducees (Tsadokim) or the Karaites (Qaraim) in Judaism.
Mention should also be made of the Reformists (principally Jamal al-Din al-Afghani, 1838-1897; Mohammad Abduh, 1849-1905; Rashid Rida, d. 1935). They tried to “reopen the gates of the ijithad,” that is, the effort of personal interpretation, in lieu of the servile imitation (taqlid) of past law doctors by present ‘orthodox’ ones, and to adapt Islamic law to the modern world influenced by Western civilization. This may be comparable to Conservative or Reform Judaism.
Note that the above list makes no mention of Persian interpreters, so that I am not sure whether it applies only to Sunni Islam, or also to the Shi’ite branch.
The innovating velleities that begun 19th Century have come to little, due to the rise of modern fundamentalism, generated by the likes of the Muslim Brotherhood (founded 1928 in Egypt, by Hasan al-Banna, of the Hanbalist school).
An allegedly ‘orthodox’ backlash started occurring in the early 20th Century, which in the last two or three decades, under the given label of ‘Islamism’, has sadly become more and more radical and extreme, indulging in blind hatred and violence towards anyone external to it.
According to a newspaper article I read (Tribune de Genève, 26-7-05), the main theoreticians of this Salafiya Djihadia movement were: Sayed Qotb (Egypt, 1906-66), inspired by Hanbalism, and Abu Al-Mawdudi (Pakistan, 1903-79), of Hanefist inspiration. Their doctrines gave rise to the notorious Al-Qaeda network, among others. The article does not mention the ideological sources of the Shi’ite Ayatollah Khomeini’s 1978 Iranian revolution, however.
Moslem intellectuals who wish to reverse this disastrous trend must begin by critically reviewing every single argument put forward by the proponents of modern fundamentalism, (a) checking it for consistency with traditional logical procedures; and (b), in cases where no hermeneutic rule has visibly been breached, considering the possibility tradition offers of alternative juridical interpretations. Many faults are likely to be found in Islamist doctrine on purely Islamic grounds in this way, even before needing to question traditional Islam and more deeply the Koran.
Another important measure is, of course, education – inoculating common people against the fallacious arguments concocted by individuals with dubious motivations. It is all too easy for religious fanaticism to take hold in populations overly prone to emotional incitement and social intimidation, and intellectually ill-equipped to insist on rational checks and balances.
 See Arnaldez, pp. 33-45, 56-57,191-197.
 I am not sure this is a good example, as neither passage explicitly excludes the other: permitting vegetable food and permitting meat are not strictly in conflict, only davqa readings make them seem so.
 Another interpretation of the clause “because” in (b) would not have the same effect. If, for instance, it meant that Z is a sine qua non for Y, then (c) would read “Only Z are Y”, which implies “Some Z are Y and No nonZ is Y”, which is not enough to infer (a) syllogistically.
 Note, in passing, the following attributions mentioned by Arnaldez (pp. 42, 57): Personal opinion or ray was used by Abu Hanifa. Istislah was used by the disciples of Malik b. Anas. Analogy was used by Shafii.