There is a long history of how philosophers conceived of the soul, from Plato and Aristotle through Augustine and Aquinas and on to Descartes, Leibniz, Locke, Reid, Hume, Kant and others.
Intellectuals from Plato to Daniel Dennett have debated the idea of the soul. C. S. Lewis believes that "A soul is that which can say 'I am'". Dualists such as Descartes and have discussed whether we are just one body or a dual being consisting of a material substance (body) and an immaterial part (soul). Other authors consider theories by neurologists and philosophers as to the nature of consciousness and its connection with a soul.
A more current debate is about interactive dualism (the notion that a separate soul acts upon the brain). But this is just a tussle between the extremes of eliminative materialism and interactive dualism, in the light of recent discoveries in neuroscientific discoveries. The arguments of those who deny the soul's existence usually fail to clearly define what the idea of what a 'soul' is, so they mostly argue against other writers who advocate the notion of an immaterial being that exists independent of the body.
The greatest value of the 'soul' apparently lies in the belief that when the material body dies, the soul survives. How does it survive? What is it made of? How will it continue to create fresh memories to build on the identity of the person whose physical body is dead? So the search for the soul continues.
The following people were intereviewed by Oprah on the topic: What is the soul?
Gary Zukav: The soul is that part of you that existed before you were born and that will exist after you die. It's the highest, most noble part of yourself that you can reach for.
Iyanla Vanzant: The soul, I believe, is the fingerprint of God that becomes a physical body. I believe that. It's the fingerprint... It's unique to everybody.
Deepak Chopra: The soul is the core of your being. It is eternal. It doesn't exist in space/time. It's a field of infinite possibilities, infinite creativity. It's your internal reference point with which you should always be in touch.
DeVon Franklin: The soul is the spirit. It is the connecting line to God. I believe the soul is where the Holy Spirit resides. I believe that it is literally, you know, when you pick up the phone and then you have your 4G network? The soul is the 4G network right to heaven to me.
Sarah Ban Breathnach: The soul is the spiritual essence of who we really are.
Daniel Pink: The soul is, I think, our capacity to see that our lives are about something more than simply the day to day, and that we're here for a purpose. It could be connected to religion or not, but that there is a purpose of your being here.
Debbie Ford: To me, the soul is a part of us that never dies. It's who we are at our core. And it carries all the messages and the lessons that we've learned in the past, and will carry all the lessons and the messages that we will carry into the future.
Eckhart Tolle: The soul is your innermost being. The presence that you are beyond form. The consciousness that you are beyond form, that is the soul. That is who you are in essence.
Michael Singer: The indwelling consciousness that watches the mind come and go. That watches the heart come and go, the emotions of the heart. And watches the world pass before you. You, the conscious, the consciousness, the center of being, is soul.
Wayne Dyer: The soul is the birthless, deathless, changeless part of us. The part of us that looks out from behind our eyes and has no form. The soul is infinite so there is no in or out of it. It is everywhere. There's no place that it is not.
Marianne Williamson: For me, it's the truth of who we are. The light, the love which is within us goes by different names, but the truth of us. Michelangelo said when he got a statue that he would go to the quarry and get a big piece of marble and the way he imagined it, God had already created the statue and his job was just to get rid of the excess marble. So that's what we're like. Inside is the being that God has already created. Some call it the Christ, the Buddha mind, the Shekinah, the light, the soul. And our job is to get rid of this excess, useless fear, thought forms of the world that actually hide the light of the soul.
Llewellyn Vaughan-Lee: The soul is a divine part of our self. It is our divine nature. It is a part of us that is one with God. Everybody has a soul. It is the immortal internal part of ourselves. It never dies. It's immortal. It belongs to God.
Jean Houston: I believe that the soul is the essence of who and what we are. I personally believe that it transcends our leaving this mortal coil. And I think it it comes with codes, and possibilities, and the next layers of who and what we may yet be. It is often a pain in the neck because it says, "Wake up. It's time to wake up. Don't go to sleep." I think it is also the lure of our becoming. That's what I think the soul is.
The Soul on YouTube Podcasts Dmoz
The Soul Connection Network
Soul Retrieval Shamanism Alberto Villoldo Villodo -YouTube