مجله معارف منطقی
پیاپی 4 (بهار و تابستان 1395)

The accuracy of inference in empirical propositions depends on three principles: 1) impossibility of absolute accident 2) impossibility of particular accident 3) justification of generalization. Different inductive schools of thought including Aristotelian rationalism and empiricism have focused on proving these principles. The first principle is a self-evident and a priori in Aristotelian philosophical school. The principle of generalization can also be justified in Aristotelian logic on the basis of the rule of "similarity of results in case of similarity of modes". The second principle can be proven by "the impossibility of accident". Empiricists have attended more to the first and second principles, justifying the problem of induction through the three approaches of certainty, preference and mental habit. According to Shahid Sadr Aristotelian opinion about the second principle is faced with three challenges: one) the limits of the rule are not specified. Two) There is no reason to prove this rule. Three) The rule is in need of an overview. Shahid Sadr levels seven objections against 'overview'. According to him, the rule of impossibility of accident is not an a priori and rational one. It is instead an empirical law that is based on the law of probability.

The fourth figure of categorical syllogism known as Galen's figure was not presented by Aristotle. This has prompted logicians to launch investigations to find out why Aristotle has ignored it. Some Western Aristotelian scholars believe the standard on the basis of which Aristotle has divided syllogistic figures does not produce anything more other than the three syllogistic figures. They have attributed to Aristotle some criteria which do not result but in three syllogistic figures. The question why Aristotle has not dealt with the fourth figure has also been attended by Muslim logicians. Following Aristotle they did not deal with the fourth figure when logic was experiencing its translation and commentary phase, but they did so not because Aristotle's standard could not produce such a form but because they thought Aristotle ignored the fourth figure for according to him it was unnatural and disharmonious. This article critically assesses the opinion expressed by Western Aristotelian scholars and lays stress on the fact that Aristotle's standard is the same as that of the later logicians who treated that question of the fourth figure. It also objects to the justification put forth by Muslim logicians for not paying attention to the fourth figure.

As the presenter of logical discussions, Aristotle has put forth numerous concepts that have dominated the world until today. Since Aristotle was a systematizer, his logical concepts have their own roots in his philosophical, ontological and epistemological concepts. This study touches on these concepts and their philosophical roots. Comparing these concepts with the concepts of fuzzy logic, it evaluates the logical, philosophical, ontological and epistemological foundations of this latter logic. It is worth saying that these two logics make use of different epistemologies. Whereas Aristotelian logic is based on a dogmatic bi-valued system, fuzzy epistemology (logic) is founded on plurality and a multi-valued system. These two logics have different understandings of the nature of mind and reality and the relation between the two.

The present study gives a particular account of essentialism and sheds light on its foundations and consequences in classical logic. It pays heed to the relationship between essence and essentialism, explaining hereby the close relation between essence and definition and the intimate relation between definition and essentialism. Given (various) kinds of definition it assesses (various) kinds of essentialism plus with essentialism in indispensable accidents, the essential in demonstration, simple (entities) etc. discussing their complicated dimensions. After enumerating the foundations and consequences of essentialism, it claims that not every Muslim philosopher and logician is an essentialist; instead some of the Muslim philosophers such as the followers of transcendental theosophy are (based on their own indisputable principles) strongly opposed to all or some of the foundations or consequences of essentialism.

According to the Holy Quran, the Holy Prophet (PBUH) was sent in order to recite divine verses, teach divine book and theosophy and to purify souls. The phrase that includes all these is 'the mission to invite people towards Allah' using certain methodologies including theosophy, good sermon, and the best form of dialectic. Allah, the sublime taught different methods of invitation to his Prophet and He himself applied these methods in order to explain His teachings. Taking the existence of intellectual reasoning – formal and material – in the Holy Quran for granted, this article studies the formal model conditional syllogism in this noble book. The verse "Eat of the good things We have given you for sustenance, and be not inordinate with respect to them, lest My wrath should be due to you And to whomsoever My wrath is due, he shall perish indeed (TÁHÁ/81)" contains a conjunctive conditional syllogism whereas the verse "f there had been in them) heavens and earth (any gods except Allah, they would both have certainly been in a state of disorder Therefore glory be to Allah, the Lord of the Dominion, above what they attribute (to Him) (Al-AnbiyÁa/22)" is an exceptive conjunctive syllogism. Whilst the verse "Say: Who gives you sustenance from the heaven and the earth? Or Who controls the hearing and the sight? and Who brings forth the living from the dead, and brings forth the dead from the living? and Who regulates the affairs? Then they will say: Allah Say then Will you not then guard) against evil (?) (saba/24)" is a exceptive disjunctive syllogism the verse "If Allah desire to take a son to Himself, He will surely choose those He pleases from what He has created Glory be to Him He is Allah, the One, the Subduer) of all (Az-Zumar/4)" is a philosophical conditional syllogism or a conditional categorical predication. This article studies various forms of conditional reasoning in the Holy Quran.

Based on inferential approach towards meaningfulness, the meaning of logical constants (ꓥ¡ ¡ …) can be obtained through the laws of introduction and omission. Giving the counter example of Tonk, Arthur Pryor proves that mere laws of introduction and omission do not necessarily introduce a logical constant. Confirming Arthur's position, Stevenson regards his counter example as the main problem of inferential approach towards meaningfulness. According to him, model theory approach towards meaningfulness is not faced with such a problem. This is because in model theory value table does not allow flawed logical constants to find their way into the logical system. The present study assesses the features of the value table that has given it such strength. The result obtained tells the value table of classical logic has two features that consist of being bi-valued (true or false) and the fact that it adheres to truth. These two features can however be procured in inferential approach.