Steamy Spirit in the Question of Soul and Body in Mulla Sadra's View

The discussion of Soul and body in Mulla Sadra's philosophy is considerably explained in view of his principles and arguments. In Mulla Sadra's phrases, 'steamy spirit' is much used – as a popular scientific theory in the past – to explain the relationship between soul and body. The existence of steamy spirit cannot be inferred from Mulla Sadra's principles; rather, he uses it in his non-argumentative explanations on the relationship between soul and body. This is because steamy spirit cannot be proved as an independent existence other than an stage of the soul, using the existing evidences including the theory of the soul's being 'corporeally contingent' and 'spiritually eternal' as well as 'intense substantial motion'. Removing this idea would not cause any impairment in Mulla Sadra's principles. Therefore, the application of steamy spirit as a scientific theory plays no role except for determining the instances in explaining the question of soul and body. This determination of instances is such that removing it would cause no defect to the theory itself.