Morteza Haji Hosseini

According to Beall and Restall’s logical pluralism, classical logic, relevant logic, and intuitionistic logic are all correct. On this version of logical pluralism, logic is considered to be normative, in the sense that someone who accepts the truth of the premises of a valid argument, is bound to accept the conclusion. So-called collapse arguments are designed to show the incompatibility of the simultaneous acceptance of logical pluralism and the normativity of logic. Caret, however, by proposing logical contextualism, and Blake-Turner and Russell by proposing telic pluralism, have sought to nullify the collapse problem. In the present article, after setting out these two approaches to the collapse problem, we argue that by using the concept of the ‘rationality of beliefs’ in order to frame the canonical purpose of logic, it can be demonstrated that if logical contextualism and telic pluralism are considered as philosophically significant logical pluralisms, a refined version of the collapse argument is still a threat for both of these kinds of logical pluralism.

According to Tarski's model-theoretic analysis of logical consequence, the sentence X is a logical consequence of a set of sentences Γ if and only if any model for Γ is also a model for X. Etchemendy, however, does not accept the analysis and critiques it. According to Etchemendy, Tarski’s analysis 1- involves a conceptual mistake: confusing the symptoms of logical consequence with their cause; 2- cannot properly explain the necessity of logical consequence; 3- faces the problem of overgeneration; and 4- faces the problem of undergeneration. In the present article, by evaluating these critiques and examining the effectiveness of some of the answers presented in defense of Tarski's analysis, we try to show that among these critiques, only the problem of undergeneration is not acceptable. According to our common sense understanding, if an argument is valid, it is truth-preserving, and by assuming the truth of the premises, the conclusion will be true as well. But it does not mean that we can reduce the logical consequence relation to truth preservation. This flaw leads Tarski’s analysis to be an unacceptable analysis of logical consequence.

Aristotle has repeatedly stated in his works that 'being has several senses'. Is this to be regarded as his pluralistic ontology, an approach that seems to be too nascent? If so, how can this newfound approach in ontology be linked to the ideas of the father of this science, i.e. Aristotle? These are the questions that the present article seeks to answer. First, we will show that Aristotle thinks of 'being' in four senses. Then, step by step he proceeds to leave different senses aside, insofar as only one sense remains: being in the sense of the figures of the categories. We argue, then, that it is better to found Aristotle's ontological pluralism upon the fourfold sorts, instead of the tenfold categories. We will provide some reasons for this preference, i.e. in defense of the fourfold sorts and against the tenfold categories. Each of these four modes of being will be discussed. Finally, a version of ontological pluralism will be provided and attributed to Aristotle: Sorting Version. According to this version of pluralism, we will demonstrate how Aristotle speaks of the ontologically fundamental structure of the world.

In a carefully-elaborated discussion, Mulla Sadra considers sensory, imaginary and rational aspects of the human soul in the transitory world. The indivisible soul, he maintains, has a rational and ideal existence before this world, a sensitive, rational and imaginary presence in this world and again becomes an ideal and rational existence in the hereafter.Fitrah and its cognates are frequent words in the Holy Koran. In every place they refer to an unprecedented creation and making.It is made to be only after instinct is contained and sensation and imagination are blossomed concurrent with the emergence of intellect. Under the circumstances, instinctive inclinations become sacred. The Holy Koran in its negative verses speaks of soul as a tabula rasa at the time of birth.Positive verses, however, make us ask ourselves, "Does soul evolve into Fitrah after intellect has blossomed?"

It was Ibn-Sina who, for the first time in the history of logic, discussed the quantity and quality of conditional propositions in detail and explained the authenticity of their generality and particularity in simple terms. He also determined the place of affirmation and negation in conditional propositions, and discovered a number of different points through his analyses of the issue. However, he mixed the ordinary logic of conditionals with their modal logic so that, due to some contradictions, no specific formal system about conditionals could be derived from the resulting logic.He was also the first person who started the discussion of conditional conjunctive syllogism, and it seems that he intended to base conditional logic on categorical logic through comparing conditional and predicative propositions with each other and pinpointing their similarities.