The logical rule of contraposition as applied to a particular affirmative proposition (I-contraposition), despite its rejection in the medieval Latin logic, had a different history in the medieval Arabic logic, varying from common acknowledgement to total dismissal (it was accepted by Avicenna and by all of his followers in the eleventh and twelfth centuries and rejected by all of Arabic logicians in the late thirteenth century onwards). This paper is a narrative of the fate of I-contraposition in the early Arabic (...) logic. I will study Avicenna’s, al-Suhrawardī’s, al-Rāzī’s, al-Kashshī’s, and al-Khūnajī’s views on this rule. Although Avicenna explicitly acknowledged I-contraposition in a brief note, and in an apparently Meinongian language, the other four figures found I-contraposition problematic and listed some counterexamples to it. Nonetheless, they all attempted to justify Avicenna’s acceptance of the rule by restricting its application conditions. These efforts led to interesting syntactic and semantic analyses but gathered little attention from later medieval logicians. Finally, in the middle Arabic logic, the revised versions of I-contraposition were also declared invalid. (shrink)

Logic; Islamic philosophy; Islam--doctrines.

Although we need the good witness of others to form our best selves, an argument can be made that we need to study the dark side of the equation as well. The understanding and analysis of bad leaders/misleaders is an important component of leadership studies. However, we argue that bad leaders should never be defined as leaders. Leadership aims at the good of its communities, while misleaders do not. Ethics, therefore, is not only essential to the practice of leadership but (...) to the very meaning of the term. (shrink)

The neutrosophic sets were known since 1999, and because of their wide applications and their great flexibility to solve the problems, we used these the concepts to define a new types of neutrosophic crisp closed sets and limit points in neutrosophic crisp topological space, namly [neutrosophic crisp Gem sets and neutrosophic crisp Turig points] respactvely, we stady their properties in details and join it with topological concepts. Finally we used [neutrosophic crisp Gem sets and neutrosophic crisp Turig points] to introduce (...) of topological concepts as: neutrosophic crisp closed (open) sets, neutrosophic crisp closure, neutrosophic crisp interior, neutrosophic crisp extrior and neutrosophic crisp boundary which are fundamental for further reserch on neutrosophic crisp topology and will setrengthen the foundations of theory of neutrosophic topological spaces. (shrink)

al-Juzʼ al-awwal. Dirāsāt fī al-manṭiq wa-falsafat al-ʻulūm -- al-juzʼ al-thānī. Dirāsāt fī al-manhaj wa-al-ʻilm al-ʻArabī.

Islamic religious educations; Islamic ethics; conduct of life.

Faults; religious aspects; Islam; Islamic daʻwah.

Knowledge; information; learning, philosophy of; teaching and study.

al-Masāʼil al-qudsīyah -- Mutashābihāt al-Qurʼān -- Ajwibat al-masāʼil.

Socio-philosophical work in response to the philosophy of Pitirim Aleksandrovich Sorokin.