In accordance with classical understanding of the principle of separation of powers, the task of a judge is merely to discover the intention of legislator and to apply it to the facts of cases. The motives behind the achieving judicial security and the existence of factors such as syllogistically form of judicial reasoning and the necessity of deduction of all the results from law has led to the traditional tendency among jurists to present judicial SYLLOGISM within the context of FORMAL SYLLOGISM.FORMAL SYLLOGISM or deductive reasoning based on FORMAL logic, reasoning possesses a necessary process and there would be no true outcome but one, and there would remain no room for doubt. A precise look at the minor and major judicial SYLLOGISM demonstrates that the notion of change of judicial SYLLOGISM to that of FORMAL, definitive, and objective is nothing but a naive fiction far from achievement. The impossibility of making the legal concept clear and the existence of defects in and of law, as well as conflict of laws, on the one hand, and impossibility of reaching definitiveness and certainty at verification of factual stage of a case, on the other hand, do not allow FORMALism and change of judicial reasoning into FORMAL and necessary reasoning.Due to the fact that judicial reasoning is unnecessary, these reasoning, unlike reasoning that are subject to FORMAL logic are not free from the intervention of human factors.The type and quality of that intervention and the usage of this flexibility and broadness by a judge are determined by the characteristic features of each legal system and the foundations concerned.

Suhrawardi claims that there can be no one-premissed SYLLOGISM, and he makes a reason for this. The issue of the current article is the genealogy of that claim and the logical evaluation of this reason. Our hypothesis is that, historically, the conflict over the possibility or impossibility of the one-premissed reasoning goes back to the Stoics: Chrysippus was the leader of the opposition; and the Antipater of Trasus was the leader of conservativism. This conflict by Alexander Aphrodisias came into the Prepatetic logic, and merged with Aristotle's Syllogistic, and, consequently, the stoical problem of "one-premissed reasoning" was confused with the Aristotelian question of "one-premissed SYLLOGISM. " Ibn Sina is the source of the transmision of this issue from Alexander to Suhrawardi. Suhrawardi's argument, if he views the refusal of the one-premissed reasoning, is, of course, incorrect; but if he is to refuse the one-premissed SYLLOGISM, he can have a good deal of truth.

The equivalence SYLLOGISM is apparently similar to a simple categorical conjunctive SYLLOGISM, the truth of which depends on the truth of its external premise of “ what is equal to the equal of something is equal to that thing” . Therefore, some believe that, by using the phrase “ result by itself” in the definition of SYLLOGISM, Aristotle aimed to derive some SYLLOGISMs such as the equivalence SYLLOGISM. It can be inferred from Ibn Sina’ s words that the equivalence SYLLOGISM is a categorical conjunctive SYLLOGISM which has lost its syllogistic form, and whose terms lack a logical arrangement. This is because the premises of this SYLLOGISM share only a part of its middle term rather than its totality. Khwajah Nasir al-Din Tusi has tried to express the syllogistic configuration and logical arrangement of the terms of the equivalence SYLLOGISM. In doing so, he has presented two types of simple and compound categorical SYLLOGISMs. He has also responded to Fakhr al-Din Razi’ s words in this regard. He believes that the equivalence SYLLOGISM lacks a repeated middle term and, hence, cannot be deemed a conjunctive SYLLOGISM. Rather, it should be viewed as a SYLLOGISM which results in a conclusion based on intellectual evidence. However, when commenting on Khawajah Nasir al-Din Tusi’ s words, Qutb al-Din Razi, on the one hand, views the equivalence SYLLOGISM of a compound conjunctive nature and believes that it is problematic to introduce it as a simple conjunctive SYLLOGISM. On the other hand, in his comments on Sharh-i matali‘ , similar to Fakhr al-Din Razi, he argues that the equivalence SYLLOGISM lacks the repetition of the middle term, and that its conclusion is evident based on its two internal and external premises. Khwunji designs a new structure for the equivalence SYLLOGISM and believes that its external premise is as follows: “ Anything equal to B is equal to everything equal to B” . Of course, this view is not immune to criticism as well. Shahrzuri believes that, if the equivalence SYLLOGISM results in concluding “ A is equal to C” , it will be out of the division of SYLLOGISM into conjunctive and exclusive types; when the conclusion is “ what is equal to A is equal to C” , he considers it to be a simple categorical conjunctive SYLLOGISM. By rejecting the view that deems the equivalence SYLLOGISM lacking in the repetition of the middle term, Mulla Sadra introduces it as a kind of compound categorical conjunctive SYLLOGISM with independent conclusions and argues that the middle term has been repeated in both SYLLOGISMs. Mulla Sadra’ s words, which are in agreement with those of Khwajah Nasir al-Din Tusi, present the correct view regarding the logical structure of the equivalence SYLLOGISM.

Muslim ligicians faced with problems in justifying certain simple reasonings (Such as equivalence SYLLOGISM) and these problems were rooted in their commitment to categorical SYLLOGISM. In this regard weakness of early logic has nothing to do with relation as such that is, it is not such that early logic was unable to prove those reasoning which contained relation due to possessing relation. On the contrary, their main problem was that they relied on the analyses of propositions in terms of subject and predicate and focusing their attention to categorical SYLLOGISM. That is, in any reasoning subject predicate and middle term should be ascertained and evidently such process is not possible every where.Therefore, equivalence SYLLOGISM reveals a defect in Aristotelian system of subject predicate - relation. For, on the one hand, Aristotelian version of SYLLOGISM requires that the premises of SYLLOGISM should be analysed into terms and each term in modern logic term is a single positional predicate. While equivalence SYLLOGISM is formed of certain premises that involve relation or categorical section of multi - position predicates. Hence referring equivalence SYLLOGISM to the conjugate SYLLOGISM is not devoid of objection.

Eleven centuries after its appearance, Aristotle’s Organon was translated into Arabic and by acquainting with such translations, some elite scholars, e.g. al-Farabi and Ibn Sina, started to write and publish logical writings in the Islamic world. These writings caused rising and developing the logic among Muslims. Analyzing and assessing the first Arabic translations of the Organon make us acquainted, on the one hand with the Muslims attention to the Greek philosophical heritages in the earlier centuries and on the other hand with the amount of these translations accuracy. Abdul-Rahman Badawi has gathered and edited the first Arabic translations of Aristotle’s Organon and Porphyry’s Isagoge in a three volume book. After comparing Arabic translation of SYLLOGISM to its original Greek and to English (Jenkinson) and Persian (Adib-Soltani) translations of the Prior Analytics, we found almost one hundred differences between them. We have categorized these differences under some titles as preference and cost of translation, unintelligible Arabic, supplemented statement, translation mistakes, change and replacement of examples, errors of editing and added explanations. In addition to indicating the significance of the translation age, we touch, in the introduction of this article, some other subjects such as Organon translation, SYLLOGISM’s translator, Badawi’s translation, methodology of comparing different translations and preferences of Arabic translation.

The SYLLOGISM in which the major premise is a conjunctive conditional proposition is called correlative SYLLOGISM. This sort of SYLLOGISM is valid in the two forms of: “ affirming the antecedent” and “ denying the consequent” and is invalid in all others forms. Correlative SYLLOGISMs have several states in the Holy Qurʼ an. In some cases, the general and specific conditions of the SYLLOGISM are fully observed, but due to clarity, some of the premises or their results have not been mentioned, and the SYLLOGISM is known as implicit and shortened. But in some other cases apparently the conditions for the correlative SYLLOGISM have not been observed and “ denying the antecedent” and “ affirming the consequent” are used for the conclusion. In this research, some of the most important correlative SYLLOGISMs in Holy Qurʼ an have been studied and in cases where it seems that the particular conditions of the SYLLOGISM are not observed, the reasons for that will be reviewed, and using the content of Holy Qurʼ an and the general rules of reasoning such as the “ correlation of hypotheticals” , these SYLLOGISM are converted to valid SYLLOGISMs and it is proven that the Qurʼ an, which is man’ s book of guidance and has invited him to think, has been revealed in human language and the general rules of thinking and intellection have been observed in it.

In his second period of logical research, which includes several books and treatises, Athir al-Din al-Abhari is the only Avicennan logician who vindicated as invalid one of the two most important Avicennan novelties: iqtirani conditional SYLLOGISM. His exposition and reasons for this invalidity in these books and treatises are various and rooted in numerous kinds of conditionals and their truth-conditions and their developments in the books and treatises. His most important reason to deny conditional SYLLOGISM is notice to the manifold assumptions used to prove the SYLLOGISMs. In this paper, we deal with the main reason, studying the mentioned differences and developments. Citing successor logicians’ points of views on Abhari’ s claim and assessment of all of them is out of the purposes of this paper and in need to other researches.

Shams al-Din al-Samarqandi, who has proposed a modern point of view in opposition of Avicenna on hypothetical SYLLOGISM, claimed that 12 of 19 moods of Avicennan valid hypothetical SYLLOGISM is indeed invalid. in another paper, I showed that if we consider only quality of propositions there emerges a surprising correspondence between his valid SYLLOGISMs and those of relevance logic. In this paper, however, I’ ll show that if we consider quantity of propositions too, this correspondence disappears. This is because discussing particular conditionals, Samarqandi held, as Avicenna did, that particular implicational conditionals can be analyzed as distinct both from universal implicational and from particular contingent (or accidental) conditionals. No analyses of particular implicational conditionals so far proposed could escape this objection

The purpose of this research is to provide a new concept in Aristotelian categorical SYLLOGISM which is called groundability. A valid mood is called groundable if one would derive all the 24 valid moods in the Aristotelian’ s SYLLOGISM by assuming only the valid mood and applying a chain of the following rules: simple conversion, reduction-ad-absurdum, sub-alternation, obversion and quantification negation. In this paper, we will prove that only the fifteen valid moods have the groundability property. Because Aristotle proves all the valid moods of other figures based on the four moods in the first figure, he considers these moods of the first figure as moods having the groundability property. We show that the groundability is not restricted to the first valid moods of the first figure--they are fifteen moods as stated. Thus, it can be shown that Aristotle's purpose from the self-evidence of the first figure is not the groundability of the four moods in the first figure. This important logical result in Aristotle's system is gained through the introducing the concept of the groundability of the moods in SYLLOGISM. We show that unlike the common view in the Aristotelian tradition, it is not the case that the groundability of the first figure must be the basis for explaining of being self-evidence of the four moods of the first figure. Regardless of what lies behind the evidence of the first figure valid moods, this paper will eliminate one of the options which is somehow a common wrong interpretation for answering the problem