MAAREF E AQLI
Year:2013 | Volume:7 | Issue:3 (25)|Papers Count:10

From distant past to the present, “induction” has been a prevailing issue in logic, epistemology and philosophy of science being discussed from different angles. Induction is of two kinds: perfect and imperfect. The latter is the focus of most discussions on induction. The accuracy of deduction in imperfect induction is dependent on three principles: a) impossibility of chance and absolute accident, b) impossibility of chance and limited accident and c) justification of extension to cases on which induction is not conducted. Different schools of thought, including the followers of Aristotelian rationalism and the advocates of empiricism, have tried to prove the afore-mentioned principles.Having presented a new theory called “the theory of essential” in his important work “Logical Bases of Induction”, martyr Sadr tries to make some critical remarks on Aristotelian rationalism and empiricism.According to martyr Sadr’s theory, imperfect induction produces objective certainty within the two stages of objective production and essential production. The first stage raises the probability and the second ends in certainty.

The lexical meaning of the word ‘knowledge’ and its equivalents in Persian language as well as other languages such as science, awareness, and understanding is clear and seems to be in need of no explanation. Nevertheless, it has different technical meanings, corresponding with different instances of its lexical meaning. They include certainty that corresponds with reality, a set of coherent statements and a set of real statements that can be proved through experiment. Keeping in mind the lexical meaning of ‘knowledge’ and ignoring its technical meanings, this article in the first place shows that the most obvious instances of knowledge in the Qur’an, while keeping in mind the way it emerges, are sensual knowledge, knowledge of the unseen and intellectual knowledge (theoretical acquired knowledge). In the second place, it analyses the way in which intellectual knowledge emerges, a process which is called theoretical acquired knowledge in logic, on the bases of the Qur’anic findings concerning the nature of thinking, making clear that, from a Qur’anic perspective, the emergence of theoretical acquired knowledge concerning an object is obtained through the clarity of that object and the clarity of that object is the product of the explanation of [relation between] that object and what it signifies.

This article is the translation of ' certainty' from The Encyclopedia of Epistemology and its evaluation. Pointing to the fact that it is necessary to deal with the concept of certainty as a element constituting the concept of knowledge in its strict sense-which is a matter of controversy between skeptics and anti-skeptics –, Peter Klein, who expounds on the entry ' certainty', emphasizing that it is the absolute certainty that is the subject of discussion between skeptics and anti-skeptics. The author goes on to mention four theories concerning the nature of absolute certainty and then presents his own suggestion. This article proceeeds with the assessment of certainty and concludes with offering [a new] criterion for determining the nature of absolute certainty using Avicennian approach in this regard.

In his introduction to I‘jaz al-Bayan, Sadr al-Din Qunawi has presented certain arguments for the fact that proof cannot produce certainty. These arguments include lack of immunity to internal doubts, external denials and objections, difference among philosophers due to the difference of the requirements of divine names, lack of mutual implication between the accuracy and inaccuracy of an argument and the accuracy and inaccuracy of a proposition and the existence of uncertainty and difference over some of logical rules.Each one of the above-mentioned arguments is faced with considerable amount of observations and reflections and none of them can prove that philosophical proof is invalid. Thus while accepting the possibility of supremacy of intuitive knowledge and the wide realm of revealed knowledge, we should accept that proof can help us reach certainty in matters related to obtaining general knowledge about general ontological issues.

Aristotle is the first logician who has introduced a “quantifier for predicate” and assessed the truth and falsity of propositions with a quantifier in their predicates. Avicenna has referred to these propositions as ‘deviated propositions’, explaining the laws of contradiction among them. He has, however, not mentioned any other rules that govern deviated propositions. Deviated propositions are divided into two groups; those that are parallel to one of the Aristotelian quarter quantifieds and those that are not as such. Combined together, these two groups constitute eight quantifieds. The relation among then can be illustrated through ‘a cube of opposition’. By formulating these eight quantifieds in modern logic, one can easily show that all these quantifieds have even conversions. This article shows that the rules of the Four Figures for these quantifieds are the same as the ‘rules of expansion of syllogism’. There is no need for a particular set of laws for every figure, though it is possible to relate for every figure its related rules.

Askari Sulaymani Amiri has found a new method for formal inference with the application of minimum rules: predicate negation and even conversion. Based on his new methodology, he has discovered some new rules which do not date back to Aristotelian logic. He has also treated some deviated propositions with quantifiers in their predicates. Among these proposition are: ‘No A is a part of B” and “Some of A is not some of B”. Moreover, he has related the laws of even conversion and syllogism for these two deviated propositions. This bold and admirable innovation suffers from certain flaws which the present article tries to remove.

Logicians use ' negation' in different senses. Sometime it is used to negate a proposition whereas at other times it is used to negate its two parts [subject and predicate]. When it is used to negate a proposition, it is used in the form of negating either its quantity or quality. However, when it is used to negate its two parts, it acts in the form of either ' negation' or ' diversion'. After relating the different uses of ' negation' in classic and modern logics and presenting their solutions for differentiating among them, this article presents their theory concerning the equality of some affirmative and negative propositions. According to this article, the negation used in a negative proposition is referred to as ‘negating predication’, the predicate of negative propositions as negative predicate and the negative proposition as containing a negative predicate. It has tried to show that negative proposition, negation of predication of the proposition with negative predicate and ' that which contains a negative predicate, ma' adula al-mahmool (a proposition in which its predicate is negative), du al-mahmool al-oduli (a proposition in which its predicated is diverted) and negation are equivocal rather than univocal. Thus, when logicians have taken some negative propositions to be identical with affirmative propositions, they have confused negative predication with one of the propositions that have negative or diverted predicates- a thing that has caused contradiction in their words. This is because some have taken negative proposition to be identical with affirmative propositions at a time when they have considered negative propositions as devoid of predication and the affirmative propositions as having predication.