What is the soul? A question many humans have asked for millennia! They are still asking. There are many great answers and understandings written about the soul throughout humanities's struggle to understand it mentally or on a rational level.
Analyzing the soul will never, ever really show you what it is for it is not comparable to the ego which is a mental construct created by the soul to interface with nature. To fully comprehend what the soul is, you must feel it. The soul is intuitive.
The soul is a form of Spirit that is projected by Spirit. It's a slowed down piece of Spirit that can participate with physical form, with nature. The soul then projects the human ego/persona/psyche as its intermediary to interface BETWEEN Spirit and form or what is known as nature. The human body is part nature and part Spirit designed as a multidimensional complex in order to have expressive abilities for expression of the soul through a physical experience. The soul is Spirit, many can't physically see the soul unless they are a seer! However, we all can sense it, can feel it when we allow this.
The soul's intermediary in our physical domain is the ego. It ensures the survival of the persona, the psyche, the physical body. Spirit's intermediary for the purpose of interfacing with nature is the soul. Remember that the soul is not a thing, it is an it. It cannot be seen, only felt and is quantum, meaning it is everywhere.
The soul needs two things: it needs inertia to repose within and develop its reflexivity and it needs movement to discover the immensities of the Universe in which it has taken form and to participate in the Universe's ongoing creation.
THE SOUL DOES NOT WORRY ABOUT HUMAN SURVIVAL AS IT RELIES ON THE EGO FOR THIS. The soul works in nonlinear ways as in intuition, synchronicity, psychic ways, mystical ways, the metaphysical. When you are attracted to someone and you don't rationally know why, that is your soul talking. The soul will make physical things happen to keep you on track in expressing your purpose here on Earth but you must listen to it, you must pay attention to it. I experienced many examples of this in myself and with others. The soul goes beyond physical appearance. It goes to feeling, intuition, that which is quantum.
The soul is felt, that's what the soul is.