مجله تاریخ علم
سال چهارم شماره 1 (پیاپی 5، بهار و تابستان 1385)

IbnSīnā is generally known as one of the most important philosophers and physicians, one whose contributions to science and philosophy have attracted numerous studies. This article provides an outline of his philosophy of science which determined the framework for his understanding of natural philosophy. Rather being of historical interest, the article argues, IbnSīnā’s philosophy of science is a useful beginning for developing a contemporary Islamic philosophy of science. The article also discusses IbnSīnā’s importance in the philosophy of health and medicine.

In the astronomy of the Islamic Period, the astronomical twilight is called “true dawn”. In the Islamic ordinances the observation of this phenomenon indicates the beginning time of the morning prayer. There are also some reports about the visibility of an elongated faint glow before true dawn which was called “false dawn”. In modern astronomy it is clear that the false dawn is caused by the reflection of the sunlight from the interplanetary dust particles, known as the “zodiacal light”, because it extends along the ecliptic. But most astronomers of the Islamic period assumed that it is caused by the reflection of the sunlight in the earth’s atmosphere, similar to the origin of the true dawn. Some of them, of course, did realize that, according to observational evidence, the false dawn cannot be caused in the earth’s atmosphere, but they could not substitute a new scientific theory to explain the real origin of the false dawn. In this preliminary survey various theories regarding the origin and appearance of the false dawn are presented from published and unpublished texts on astronomy of the Islamic period.

Culture and Civilization Dept., EncyclopaediaIslamica Foundation, Tehran Hunayn b. ’Ishāk is one of the most hardworking scholars of Islamic period. He has many works and translations on medicine, philosophy, logic, ethics, natural sciences and Christian theology. This article is to introduce his most important works on medicine, philosophy and logic and also to present a brief report of his views about Christian theology. Table 2 is also a useful summary of Hunayn’s treatise on Galen’s works which contains a rather complete list of his circle’s medical translations.This article is in fact the second part of a survey which its first part entitled “Hunayn b. ’Ishāk’sTranslationSchool” is published in the last issue of this journal.

This article is tointroduceone chapter of al-Bīrūnī’s treatise on astrolabe entitled: Kitābfī‛ilm-i al-Asturlāb (A book on astrolabe knowledge). This chapter is about finding kibladirection by Astrolabe. Also, it argues dependence of various astronomical traditions and interaction between astronomy and Islam. World-map centered Mecca and additional graphs on astrolabe are examples for showing this dependence. There are mathematical explanationsalthough they are not goal of this paper.

KadiSa‛idAndulusī, scientist and historian of 12th century, wrote a book entitled al-Ta‛rīfbi-Tabakāt al-’Umam on people classifications and their characteristics. But this book has specific point of view about science which puts it in the history of science category. This paper is to investigate this book’s rank in this category by the modern standards of the historiography.

From the year 1926/1305, Solar Hijri Calendar is used in Iran as the official calendar. In this calendar, each year is consisted of 12 months which 6 of them have 31 days. Next 5 months have 30 days and the 12th month has 29 days. Just in Intercalary years, the 12th month has 30 days. The base of the Solar Hijri Calendar is the time when the prophet of Islam traveled from Mecca to Medina in the 7th century. Solar Hijri calendar can be assumed as the most exact calendar ever exists in the world. One of the reasons caused this calendar to be so exact is that there is Intercalary years in this calendar, which have years distance to meet next Intercalary year. This is different from the other solar calendars which have 4 years duration for Intercalary years. But there is no explicit rule to when to apply these 5 years durations for Intercalary years.This caused the past and the present scientists, who studied about this calendar, present different ideas about how to apply Intercalary duration. In this study we try to review a report about the methods, presented by past scientists and after that we present currently scientist ideas about Intercalary calculation tables. As our view this study will help us to compare different scientist’s theories and to find which one is more exact.