Avicenna (Ibn Sīnā) was and remains the pre-eminent Islamic philosopher. AL-MADKHAL, the first part of the logic of his masterwork AŠ-ŠHIFĀ, is a commentary of Avicenna (Ibn Sīnā) on Porphyry’s ISAGOGE. AL-MADKHAL is the only part of Avicenna’s logic included in the Medieval Latin translation of Avicenna’s works. There, known as the LOGICA, it had wide influence, especially in the thirteenth century. In addition to remarking on the text of the ISAGOGE in a very critical way, Avicenna gives an overview of his entire work. While Porphyry says that he will avoid difficult questions about universals, in contrast Avicenna considers their status. AL-MADKHAL contains a major discussion of Avicenna’s theory of the threefold distinction of quiddity, said by De Wulf to be the main medieval solution to the problem of universals. The translation comes with Notes and an Introduction, placing AL-MADKHAL in context.