Those holding to a strict naturalistic worldview-a philosophical position that there are no mental life, no immaterial, supernatural reality- run into problems of human person hood and that of the nature of consciousness. For the atheist, human persons being a soul would be incompatible with naturalism. Is such a position correct? Do we have reasons to accept even the possibility of the soul? Briefly we’ll examine what is the nature of consciousness? And if there are any reasons to posit the possibility of the immaterial soul? Further we’ll look at what it means to have a conscious mental life of which one of the elements of consciousness is intentionality, the bringing about of some event that an agent intends or wills to do so.
What are mental states?
When we say that we have consciousness, what we mean is what occurs when one engages in the reflective self. Your own subjective experiences of thinking, feeling, being aware of your own mental states. For instance, “I have a pain (p) sensation that I’m currently aware of right now.” Consciousness is definable by referents to mental states. Example, I can be consciously aware of my own mental states being different from a chemical-neuronal state localized in the brain. Qualitative experiences of feeling helps us understand this, I feel a certain P sensation in my lower abdomen. I’m fully aware of how ‘I’ feel, the sharpness of pain is what ‘I’ experience. Even though there is dependence upon brain firings of pain receptors in response to my abdominal pain, it still follows that my subjective P experience is not the same state as the neuronal firings in the physical brain. There is something more.
What does it mean for someone to intend to do something?
We naturally understand the ability to perform human actions. I act to bring something about, say the reaching out of my hand, and clenching of the keys as I open my car door, because I made a conscious decision to do so. Such willful intention was not because of forced physical laws to which I’m subject to. Intentionality is the mark of the mental. As long as I can ‘intend’ to do something, will some causal action, then mental states will always be just that, mental properties and not physical properties. Acts, wanting, purposing, intentionality are caused by mental events.
Mental states are states-such as beliefs, desires, sensations, deliberations, that are self-directed. That is conscious experience has a privative nature to it, affecting the self or bearer of consciousness.
What is the Soul?
Having briefly examined mental states we now can give reasons for the immaterial soul. You see, physical properties, such as the brain, cannot account for our conscious states since consciousness is immaterial and not reducible to physical brain states (neuronal chemical firings in the brain). While consciousness may use the brain or be dependent of it to perform certain actions, for instance, the intending or decision to move ones arm as neural firings connect to areas of the brain signaling motor neurons to physically move one’s arm. Yet, this is only possible because of a purposing effect of ones subjective, inner mental states of the person deciding or willing to move their arm.
The soul then has the capacity of consciousness/awareness of the self. Inside consciousness are mental states (the soul is the subject of conscious states). intententionaity is one of the mental states that the soul is aware of to interact with their subjective self and the external world around them. Our beliefs, desires, emotions, sensations, imaginations, deliberations, self-awareness…all takes place in a conscious, immaterial soul of which you essentially are!
A strict materialist worldview cannot account for conscious states or any mental states. On their view it becomes impossible to even have knowledge, be aware of one’s own thoughts, have freedom of the will or human purposing, have language and the use of self-reflection to reason and so on. Because a strict materialist philosophy cannot get real conscious mental states from purely physical, non-living matter. Favoring human person hood with a real non-physical mental life then, is highly probable that the existence of the soul is the correct understanding of the nature of consciousness. Theism has always held that an immaterial reality exist, the greatest conceivable being known as God. Who is responsible for the beginning of the universe and all living things.
 Naturalism in relation to the mind-body problem, that there is a connection/interaction between mental states (mind) and physical states (the body/brain) yet the connection of such separate entities lies in a mystery. See’s no such mystery and equates the mind and body as one substance or entity, as being physical. (see Gilbert Ryle, The Concept of Mind (Routledge,1950). Who argues that the official doctrine is the commonsense view is that every human being is composed of both a mind and a body which are harnessed together yet separate and distinct things . After the death of the body the mind continues to function and exist. He later argues that such a doctrine is absurd, favoring a behavioral/physicalist perspective.