Answer Set Programming is a new paradigm based on logic programming. The main component of answer set programming is a system that finds the answer sets of logic programs. During the computation of an answer set, systems are faced with choice points where they have to select a literal and assign it a truth value. Generally, systems utilize some heuristics to choose new literals at the choice points. The heuristic used is one of the key factors for the performance of (...) the system. A new heuristic for answer set programming has been developed. This heuristic is inspired by hierarchical planning. The notion of criticality, which was introduced for generating abstraction hierarchies in hierarchical planning, is used in this heuristic. The resulting system (CSMODELS) uses this new heuristic in a static way. CSMODELS is based on the system SMODELS. The experimental results show that this new heuristic is promising for answer set programming. A comparison of search times with SMODELS demonstrate CSMODELS’ usefulness. (shrink)

Khalīfa b. Khayyāt(d. 240/854-855) was an historian- muḥaddith in the ʿAbbāsid’s period. There are references in sources to his competence in history and lineage rather than Ḥadīth. Two works of him have survived. The first one is al-Ṭabaḳāt which is about study of men and the second one is al-Taʾrīkhwhich chronologically narratesthe events in the history of Islam until 232 AH. The latter is the most significant work to be applied for the historiography of ibnKhayyāt. In this article, Khalīfa b. (...) Khayyāt’s methodology in historiography is examined. In this study, the early period of Islamic histography is handled and the subject is discussed comparatively. The main characteristics of his historiography are his adoption of a chronological style that facilitates the follow-up of the book, his knowledge for the lineage of those who died in wars and the details about the wars. Also, among the charactersitics are his application of isnād to his history book as a muḥaddith, his knowledge for the previous resources via his teachers who belong to the schools of al-Madīna and ʿIrāḳ and when required, his usage of ayah, ḥadīth and poems. These issues are dealed in the artcile with examples. Besides, a study in the West about Khalīfa b. Khayyātasserts that he was a follower of Umayyad dynasty and so this affected his historiography. In this article, this assertion is tackled by analyzing the whole book and it concludes that it is not valid because of some narrations against this assertion.SummaryKhalīfa b. Khayyāt (d. 240 / 854-55), who grew up in Basra, one of the most important centers of scholarship of the time and the meeting point of scholars, and he continued his scholarly works in this city. Since his grandfather and father are engaged in the field of Ḥadīth, Khalīfa b. Khayyāt started his scholarly adventure at an early age and he took his first education in the field of Ḥadīth.Scholars, in the early periods, continued their studies in the fields of sciences related to each other. Khalīfa b. Khayyāt’s studies are also in this kind. Although there are references in sources to his accumulation of Ḥadīth, Khalīfa b. Khayyāt ’s main area of ​​expertise is history and nasab/genealogy. The fact that his works and references to him in later sources are largely related to historical events, knowledge of the nasab/genealogy, and wafayāt (death dates of Ḥadīth scholars and narrators) reveals his considerable knowledge on these issues. Khalīfa b. Khayyāt lived in the period of ʿAbbāsid caliphs al-Maʾmūn (813-833) and al-Muʿtaṣim (833-842). This period is important because of the fact that the al-Mihna incident took place and the pressure on the Ḥadīth scholars increased. Although Khalīfa b. Khayyāt is not one of the direct opponents of Muʿtazila, his participation in a debate against them provides clues about the place where he stands. The scholarly atmosphere of Basra, enabled Khalīfa b. Khayyāt to benefit from a wide range of teacher-student network. In addition to his professors from whom he benefitted in the field of Ḥadīth, he had the opportunity to obtain the knowledge and understanding of the history of that time through his teachers who are important historians of the period in his field. Two works related to Khalīfa b. Khayyāt whose reliability is confirmed by djarh wa l tadil scholars reached to our time. One of the oldest Ṭabaḳāt works in the history of Islam is al-Ṭabaḳāt; the other one is the book, al-Taʾrīkh, which provides a new method for Islamic historiography.This study deals with the principles of the method of historiography, which can be put forward through Khalīfa b. Khayyāt 's al-Taʾrīkh. al-Taʾrīkhis important in terms of being the first example of chronological writing type in Islamic historiography and has not been subject to any independent study to date. There are two ongoing M.A. thesis about Khalīfa b. Khayyāt, however, no study has been identified that directly deals with its methodology of history. On the other hand, based on some riwāyats/narrations in al-Taʾrīkh, there is a work that claims that Khalīfa b. Khayyāt had sympathy towards Umayyads. The study named “Khalīfa b. Khayyāt’s History on the Umayyad Dynasty (660-750), prepared by Carl Wurtzel as his PhD. Dissertation, examined the life of Khalīfa, partly the historiography and the religious-political narrations in the work. On the case of Muʿāwiya’s (d. 60/680) request of the allegiance to Yazīd (d. 64/683), Wurtzel compared an event that took place between the envoy of Ibn al-Zubayr (d. 73/692) and Muʿāwiya with al-Balādhurī’s (d. 279/892-93) narrative and concluded that Khalīfa was an Umayyad sympathizer. However, Khalīfa b. Khayyāt’s exclusion of an event such as al-Mihna which was against the ʿAbbāsid and changed the course of history in his book, shouldn’t be considered as a symptom of sympathy; It would be more appropriate to accept it as a feature of history writing.At the top of Khalīfa b. Khayyāt's principles of historiography, adopting chronological method comes first. Accordingly, Khalīfa b. Khayyāt, gives a brief history about the siyar of the Prophet Muhammad at the introduction of the book. Then, by beginning from the first hijri year, he gives the important events, wars and deaths by the years. Sometimes, he refers to the people assigned by the caliphs of the period by referring to the Amîrs (Administrators) of the Hajj. He gives lists of those who died on both sides of the wars. The importance of mentioning the tribes of the deceased shows his competence in the knowledge of nasab. One of the highlights of his historiography is that he sometimes does not touch upon some of the events and situations that are considered to be turning points in Islamic history; and sometimes he does not go down into detail but just gives relevant narratives. For example, he doesn’t mention any narrations about the selection of the Caliph which perhaps the most fundamental point of separation between Ahl al-Sunnah and Shīʿa in the history of Islam.Although he gave detailed information about The Battle of The Camel (36/656) and Ṣiffīn cases (37/657), it is not possible to determine his views on this subject. In addition, he never mentioned the al-Mihna incident, which deeply influenced society and the scholarly environment during the ʿAbbāsid period. Isnād is also holds an important place in the methodology of history of Khalīfa who was a muḥaddith at the same time. In many of the narrations he used the words haddathanā and ahbaranā.In our study, the siyar section of al-Taʾrīkhwas examined in order to determine the sources of the Khalīfa’s historiography and has been seen that the works of Ibn Isḥāḳ (d. 151/768) and Ibn Hishām (d. 218/833) were the main sources of this chapter. Considering Khalīfa b. Khayyāt’s emphasize to isnād and his reach to Ibn Isḥāḳ 's work through the mediation of Bekr b. Suleiman, it can be said that he was dominant in historiography on the sources before him. Khalīfa b. Khayyāt rarely refers to Qur’anic verses and hadiths when describing events. He referred to the verses in only two places and hadiths in only five places. One of them, and perhaps the most remarkable one in the book is the Ḥadīth of the Prophet Muḥammad: “I am the guardian of whom; ‘Alī is his guardian” This narration is used in the letter of Caliph Mahdī (d. 169/785) of the ʿAbbāsid to khārijī (outer) Abd al-Salām b. Hishām who rebelled. The study is based on the principles outlined above. At the end of the study it is also considered that Khalīfa b. Khayyāt ’s works should be the subject of graduate studies which should be prepared with deep readings. (shrink)

PREFACE WORD -/- Hilmi Ziya Ülken was born in Istanbul during the last period of the Ottoman Empire, was educated during this period and worked in many areas of the intellectual life of the newly established Republic. Although he was interested in many fields of social sciences, he gained fame in philosophy, sociology, history of thought and literature. Again, he undertook important tasks in revealing and introducing medieval Islamic thinkers and post-Tanzimat Turkish thought, and due to his deep knowledge of (...) Eastern and Western philosophies, he made comparative studies in these fields and tried to reveal the similarities and differences in both cultures. Many graduate studies, book chapters and articles have been written about such an important thinker whose works are also recognized abroad. Among the thinkers of the Republican Era, Ülken is one of the most studied names. In this study, Ülken's biography, his intellectual adventure, his understanding of philosophy and his ideas about the life of thought are discussed panoramically, and the bibliographic information obtained about his articles and other works that have not yet been fully revealed has been added to the study. Another important document added to this study is Ülken's biography written in his own handwriting. Our hope is that with the completion of the information missing in this study, a complete portrait of Ülken will be revealed. When Ülken's works are taken into consideration, it is understood that he wrote works in many fields of social sciences. The fact that he did not concentrate on a certain field but worked in many fields has been a frequently criticized aspect of him. In this sense, we think that the phrase "A Thinker of Mütebahhir", which we wrote as a subtitle to the title of our study, defines him very well. Many names have used the adjective mütebahhir, which means ocean and depth in Ottoman Turkish, about Ülken. While Necati Öner used it in a positive sense, names such as Cemil Meriç (1916-1987) and İsmail Tunalı (1923-2015) used it in a sense that includes negative connotations, such as saying words in every field, his knowledge is unlimited but formless and non-systematic, and Salâh Birsel (1919-1999) wrote on every subject. On the other hand, scholars such as Kurtuluş Kayalı and Ali Utku, who have recently conducted competent studies on Ülken, have emphasized that Ülken - contrary to popular belief - thought and worked within a system and was very sensitive about his system of thought. When Ülken's works are examined in general, it is seen that many of them were formed by turning lecture notes into books, and this situation caused many problems. This situation led to problems such as the disorganization of his works, the lack of a certain systematization, the lack of the necessary methodological sensitivity in footnotes and citations, and the use of some terms in their original language instead of their Turkish equivalents. When we look at the life stories of important thinkers in the history of thought, we observe that they were not only influenced by the social, political, economic, etc. conditions of the period in which they lived, but also that they influenced these conditions in the period in which they lived. The best example of this situation among the thinkers of the early years of the Republic is Ülken. When his works are examined in chronological order, it is noticeable that his ideas constantly changed, that he had to defend the ideas he criticized from time to time, and that he was in a constant search. He explained his works in many fields by saying that he wrote works that would be a source for his own works and that he served as a bridge to the past. The fact that he was a doyen in many fields of social sciences despite having a Mülkiye education can be explained by his self-education. Ülken, who set an example for academics and thinkers with his hard work, diligence, and lifestyle of constantly reading, researching and writing, carried out very important works in his 73 years of life. As Öner, a student of his who knew him closely, says: "In his daily life, Ülken was either reading, writing or philosophizing." Again, Tunalı says about his diligence that "when he was finishing a book, he would have written another book!" It can be said that one of Ülken's efforts was to establish a tradition of sociology and philosophy in Turkey by recognizing the disconnect in our world of thought. Ülken expressed this to his student Necati Öner by saying, "We are a quarter in philosophy, you will be half, and then we will be complete!" While the influence of philosophers and sociologists who came to our country with the educational reforms was quite limited, Ülken succeeded in establishing a tradition in Istanbul Sociology and Ankara Theology. For this reason, important sociologists and philosophers of our country, such as Baykan Sezer (1938-2002) and Kurtuluş Kayalı (born 1949), admitted that "we are students of the Ülken tradition" even though they were not his direct students. Ülken provided an important opening in the social sciences with his methodology that analyzed the problems he dealt with in depth, tried to deal with all aspects of the issues and made synthesis attempts between different ideas. In addition, with the newly established Republic, he made great efforts to collect and translate sources in many fields, especially philosophy, and to carry out activities on a philosophical basis. The fact that his works continued to attract attention in every period after him and were reprinted and read again and again reveals the centrality of his role in the intellectual life of the Republican period. In this study, in which the life, philosophy and thoughts of Hilmi Ziya Ülken, whose valuable contributions to Turkish-Islamic thought are undeniable, have been tried to be presented in general terms, the articles and book chapters I have written about Ülken in various journals and book chapters and whose titles I have given in the bibliography and bibliography section have also been utilized. I hope that this monographic study will make a small contribution to the studies on Ülken, who deserves to be remembered with mercy and gratitude. -/- . (shrink)