Abstract

The problem of the soul is one of the important philosophical problems that has attracted the attention of thinkers since ancient times. Therefore, various opinions have been put forward regarding its nature and existence during the history of human thought. Apparently, Aristotle was the first philosopher to provide a clear definition of the soul. Among Muslim Peripatetics, following Aristotle, Ibn Sina defined the soul as the first perfection for the natural organic body and, through analyzing its specific features, tried to remove the short comings of Aristotle's view. Through influencing the Aristotelian definition by his religious attitude and insight and acknowledging the immateriality of the soul from the beginning of its creation, Ibn Sina presents a view of the soul which is to some extent close to that of Plato and the theory of the duality of the soul and body.Like Ibn Sina, Mulla Sadra apparently accepts the Aristotelian definition of the soul; however, given the fundamental principles dominating his Transcendent Philosophy, his comprehensive view, and inter-disciplinary approach, he defines the nature and reality of the soul in a way that, in addition to removing all the ambiguities and defects involved in the Peripatetics' definition, leads to some other basic consequences and differences in the domain of the problems related to the knowledge of the soul