Overview: review: body and soul, defining the soul, living things, nature and function, reproduction and immortality, soul as cause, living and living well. The soul (psuch ) is a principle of life: to have a soul just is to be alive: principle of life, principle is metaphysical source, have a soul is to be alive. It is neither a body nor an immaterial thing temporarily inhabiting a body. The study of the soul is first and foremost the study of the capacities and activities characteristic of living things: all living things, including plants, absorb nourishment, grow and reproduce (the. Nutritive powers): everything living thing, animals also perceive (all have at least the sense of touch). Many also remember, form mental images, form desires and move from place to place: they move around, memory, human beings along among the animals think and understand: human beings alone are rational animals.