Application of the method istihsan in the chapter al-Kitab al-Buyu? wa as-Salam in the book kitab al-Asl of Shaybani

This is a study of the concepts of istihsan and qiyas in the chapters of bay` and salam of Kitab al-Asl of Muhammad b. Hasan as-Shaybani. Kitab al-Asl is the most important source of the Hanafi legal inheritence.The study is consists of three chapters. The first chepters gives İmam Muhammad?s life with introduetors remembly about his Kitab as-Asl. The second chapters introduce islamic legal rules regarding bay` and salam as well as to become dense on istihsan in the history of islamic legal theory. The third chapter; the most important chapter of this study consist on simples selected from the chapters of ?Buyu` And Salam? what contain the terms of istihsan an qiyas. Here the examples are analized in order to understand what is the shaybani meant this terms.