Mulla Sadra and the mind-body problem:
A critical assessment of Sadra’s approach to the dichotomy of soul and spirit

Abstract

Abstract
The presence of some ambiguity about the two terms of soul and spirit, which up until now has not been considered, has been investigated in this research. This ambiguity has created problems in different fields of study such as philosophy, psychology and commentaries of religious texts. This is because the two words are usually used synonymously.
The main aim of this research is to investigate whether the human being has an independent spirit in addition to the body and the soul or not. In other words it is attempting to establish if man is a tripartite existence made of body, soul and spirit.
In order to attain this aim the ideas of various philosophers are discussed on different subjects regarding the soul with particular attention to the philosophical system introduced in the seventeenth century AD by the Muslim philosopher, Sadr al-din Shirazi. This consisted of two other philosophical systems in Islamic philosophy, peripatetic (mashā‟) and illuminative („ishrāq) combined with mystical and religious teachings. His idea about the soul was set as the basis for the arguments regarding the soul and the ideas of other philosophers were compared to it.
This research explores the principles that form Sadra‟s beliefs about the soul. One of Sadra‟s principles, the fundamentality of existence, is explained. This principle aims to prove the reality of the external world and the soul as one of these realities. The topics of motion and time and the views of philosophers about these are cited. In addition, another Sadra‟s important principles, trans-substantial motion, is mentioned and explained and it is suggested that the difference between Sadra‟s and other philosophers‟ ideas about the soul lies in accepting or rejecting motion in substance. According to Sadra, the soul which is material at the beginning of its creation moves towards immateriality by trans-substantial motion.
Then philosophers‟ ideas about the soul are mentioned as well as their disagreements regarding different issues such as immateriality, motion, origination of the soul etc. In addition, the problem that Sadra‟s philosophical system faces in regard to the soul is discussed in particular since it is the main aim of this research.
It is concluded that Sadra‟s idea is more complete than the other ideas regarding the soul. The existence of the soul found a better justification in this idea. The problem of dualism of the soul and body with which other philosophers were faced has been resolved. Meanwhile the problem of this philosophical idea which sees the soul to be the same as the spirit was investigated and it was stated that this problem has caused many diversities of opinion between philosophers in subjects related to the soul. The propounded solution for all the cases was to accept the dichotomy of the soul and spirit. Religious texts have been classified, analysed and used to support this idea and by using different evidences it was confirmed that the soul and the spirit are two independent substances and that the human being is a tripartite existence.