The Argument from Consciousness
The argument from consciousness takes the nature of mentality as evidence for God’s existence. It can be seen as a teleological argument, taking the harmony in the relationship between mind and body as evidence of divine design.
The Irreducibility of Mind
The first key idea in the argument from consciousness is that mental events are something over and above physical events. Although there is strong evidence that there is a connection between mind and brain, mind and brain are not the same thing. Whatever connection there might be between mental states such as beliefs, thoughts, and feelings on the one hand, and brain-states on the other, the connection is not identity. Brain-states have a specific location; mental states do not. Brain-states are as they independent of any perceiver; mental states are not. Consciousness is something more than a physical process.
The connection between mind and body is, however, a strong one. Mental events cause physical events; for example, your decision to stamp on my foot causes your foot to land rapidly on mine. Physical events also cause mental events; for example, your foot landing on mine causes me to feel pain. There are laws that govern mind-body interaction. Mental and physical events are correlated.
The Explanatory Failure of Naturalism
Naturalism, arguably, cannot explain this. The difficulty of explaining how two things as radically different as mind and body could be causally related is called the problem of mind-body interaction. It is so intractable as to be the best argument for materialism and against the irreducibility of mind. The only adequate explanation of the connection between the two, according to the argument from consciousness, is a theistic one: God maintains the harmony between mind and body.