فصلنامه معرفت فلسفی
سال هفتم شماره 4 (پیاپی 28، تابستان 1389)

The prevalent view among epistemologists about “mental forms” is that they designate things by essence and in actuality. Ayatollah Fayyaḍi accepts this idea, but renders such a designation an instance of knowledge by presence and has a different view about the designator.The authors in this article try to compare the two theories and analyze their commonalities as well as their differences. Fayyaḍi believes that the designator is not the mental form, but the soul of the perceiving agent. He thinks that the designator of the objective things shows subjective designator, objective designator, and all its instances at the same time, and this is the implication of designation by essence. He introduces knowledge be presence as the source by which one can understand the mode of such a designation and all its attributes, and suggests that by esoteric analysis one can find out about such matters. Although he renders the designation of simple concepts, propositions, and judgments essential to them, he thinks that there are differences in the way of their designation.

The author of the article has already analyzed Objective and verity propositions (القضايا الحقيقية) within the framework of modern logic. In one of them, he uses modern modal logic for formalizing verity propositions, and in the second one, he uses the undefined predicate of existence for formulating objective propositions. The second article introduced some definitions for existence in identity logic and in second-order logic, but was unable to use such definitions in its analysis of the objective propositions. In this article, basic flaws in identity logic as well as second-order logic in the analysis of objective propositions are shown, and a weaker logic, called “the logic of the omission of identity” is suggested which is believed to be able to express objective propositions. Furthermore, a weaker logic, compared to the standard second-order logic, called “second-order logic of Henkin” is employed, and its ability to formulate objective propositions is demonstrated. It argues for the idea that logic of Henkin is congruent with primary intelligibles, while standard logic is harmonious with secondary intelligibles.

The inquiry about the mode of the existence of natural universal, or quiddity, can be regarded as one of the complexities in the philosophies of Ibn Sina and Mulla Sadra. Natural universal has a different definition and consequences in the structure of each one of the two philosophies. To ignore such differences may cause numerous mistakes. Non-conditioned quiddity is nothing other itself, and this is while Ibn Sina claims that such a quiddity (natural universal) has objective existence. The question arises as to how it is possible for the non-conditioned reality to exist without losing its attribute as being non-conditioned.The authors in this article want to show that Ibn Sina has left some questions unanswered in his treatment of the issue of the mode of being natural universal enjoys, and Mulla Sadra has tried to find a justified answer to such problems without contradicting his most essential theory of the principality of existence. The article argues for the superiority of Mulla Sadra’s theory and the way it is congruent with the theory of the principality of existence.

Stephen Read has tried, in the recent decade, to suggest a new solution to the Liar Paradox by proposing a new theory of truth. He criticized Tarski’s truth theory and suggested a new theory instead. By applying his theory, Read concluded that the liar sentence is false without any contradiction. The author in this article tries to show the similarities of Read’s approach to that of Athir al-din Abhari.

Despite all the disagreements about the definition of A priori knowledge, all philosophers seem to agree on the major role “experience” plays in its difference with A posteriori knowledge, and the idea that the degree of this role in the justification of knowledge is the basis for such a division. Obviously, to determine the limits of experience is essential for explaining such distinction. There is also a question to be answered as to whether it is possible to have both a priori and a posteriori knowledge of one proposition. In other words, whether being a priori or a posteriori is rooted in the proposition itself, or external elements determine the suitable source of justification? It is held by most of the contemporary epistemologists that there is no contradiction involved in having both a priori and a posteriori knowledge of one proposition.The author in this article tries to first explain the meaning of experience, and secondly, to argue that the root of the distinction between the two types of knowledge is in the propositions themselves, and it is impossible to have both kinds of knowledge of one proposition.

The Theory of Ideas suggested by Plato has had a great impact on different fields of philosophical discussion because it suggests a wider universe including being with a distinctive feature. Shaykh Ishrāq, Shahābuddin Suhrawardi sympathized with this theory. He gives a determining place to “ideas” in his ontological system and tries to establish it through firm arguments. He also makes all his efforts to give this theory a more plausible and more rational structure by explaining the relation of the world of ideas with its superior and inferior worlds. This article is an inquiry into the definition and nature of ideas from the viewpoint of Plato and Shaykh Ishrāq, the latter’s arguments for establishing such a world, and the place of this theory in the ontological system of the two thinkers. The main objective of the author, however, has been to investigate about Suhrawardi’s point of view; therefore, Plato’s theory has been discussed in order to show the commonalities and the differences between the two theories.

Existence is one of the most basic concepts in the philosophy of Hegel as it is a starting point in his logic. This article inquires about this important concept in the thought system of Hegel. The authors discuss Hegel’s idea about the unity of existence and consciousness, its abstract nature because of the rules governing Hegel’s triads, and Hegel’s arguments for existence being a primary concept. They will look into his justifications for building other concepts on this basis, as well as his divisions for existence. The way Hegel differentiates between existence and being is another issue to be discussed in this article. The authors also criticize Hegel’s ideas in these regards.