The soul has a fluid existence and, in the context of this fluid existence, it gets the possession of the following stages: elemental, natural, mineral, vegetate, animal (ideal abstraction) and thinking (rational abstraction) respectively. On the one hand, the essential relationship between the body and the soul as well as the existential union of the two and true attribution of the natural and vegetate actions to the soul, and the occurrence of motion and change in the realm of the knowledge and habits of the soul on the other hand show the fluidity of the soul. Considering the existence of the fluid soul and the essential relationship between the body and the soul, we must regard the soul as the first perfection for the natural body. This perfection has – in addition to the material natural mode and essential belonging to the body – abstract mode and is considered the origin for all signs of life in its own body.